INSTRUCTION
stringlengths 25
999
| RESPONSE
stringlengths 0
999
| SOURCE
stringlengths 16
38
| METADATA
dict |
|---|---|---|---|
Show with delay directive
I'm pretty new to AngularJS and have made my first directive. Is this a good or a bad way to do this? It works, but can't figure out if this is clever or not.
.directive('showWithDelay', function($timeout){
return {
restrict: 'A',
link: function($scope, $element, attrs){
$element.addClass("ng-hide");
$timeout(function() {
$element.removeClass("ng-hide");
},attrs.showWithDelay);
}
}
})
Usage in template
<a class="button button-block rounded" show-with-delay="6000">CLICK ME</a>
button will be displayed after 6 sec. | Looks fine to me, I would add some small changes:
If you create a directive/service/controller/.. in Angular it's a best practice to create them with the `[ ]` notation to make sure minifying your code won't break:
.directive('name', [ '$timeout', function ($timeout) {
} ] );
In your example a minifier would change the $timeout variable to something as `'a'` which will result in an error because `'a'` is not registered and thereby not known by Angular's dependency injection system.
In my example if a minifier would change $timeout it doesn't matter at all since a minifier doesn't change string values. A rule of thumb, always ngminify your code before jsminify.
And as last I would add a default value for the timeout function:
$timeout(function () {
$element.removeClass("ng-hide");
}, attrs.showWithDelay || 5000);
This way if someone does not provide an attribute it will take the default value of 5000. | stackexchange-codereview | {
"answer_score": 3,
"question_score": 2,
"tags": "javascript, angular.js"
} |
Is it bad to have a javascript timer constantly running (for session checking)?
I am contemplating creating a 1 minute session logout warning message.
To do this, I assume I will need a javascript timer constantly running in the background.
Is this a terrible use of resources to run a timer constantly like this or is it small enough not to matter? | You don't need a constantly running timer, you just need to use `setTimeout` set for 1 minute. If you idea is that this should be a inactivity timer, then all you need to do is clear it with `clearTimeout` and reset it when the user does something.
You could do something like:
var timerID;
function startTimer() {
clearTimeout(timerID);
timerID = setTimeout(function() {
// Put your warning or auto logout here
}, 60000);
}
function UserIsDoingSomething() {
clearTimeout(timerID);
// do something....
startTimer();
} | stackexchange-stackoverflow | {
"answer_score": 6,
"question_score": 2,
"tags": "javascript, session, timer"
} |
How do I check the html status code when calling xml_read using the xml2 package in R?
**TL;DR** : See title
**Details:**
I'm currently querying an XML API that's a little quirky.
Sometimes when you make a request, you get back an XML file of the data requested. Other times, you get back an XML file with a message that says your request has been queued.
I've thought about using xpath queries to see if the data I'm expecting is there before continuing on, but it's entirely possible that a valid, properly served query will result in an empty set so this will sometimes yield a false negative.
One saving grace is that the server will return a different HTTP status code when it is queueing the request. However, I don't know how to inspect the result of `xml_read` to tell what the code is and the documentation does not seem to provide any guidance. | Something like this may help. The idea is to get the document and check the response code, then provide the document to the XML api How to determine if a url object in R base package returns '404 Not Found'? . BTW, did you mean `read_xml` from `xml2` package or some other package? | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 0,
"tags": "r, xml parsing, xml2"
} |
Mapping binary data in perl
I have the following predefined codes that represent an index in a binary bitmap:
0 = standard
1 = special
2 = regular
3 = late
4 = early
5 = on time
6 = generic
7 = rfu
An example value I would take as an input would be 213, which becomes 11010101 in binary. Index 0, 2, 4, 6, and 7 have their bit flipped indicating that this record is: standard + regular + early + generic + rfu.
I am trying to figure out in perl how to take that binary data and build a string, like mentioned above with code + code + code, etc.
Any help would be greatly appreciated. Thanks.
Edit: My thoughts on how I might approach this are:
1. Convert decimal to binary
2. Find length of binary string
3. Using substr get the value (0 or 1) index by index
4. If index value = 1 then add relevant code to string
Is there a better way to go about this? | You can test bits on input from 0 to 7, and take only these that are set,
my $in = 213;
my @r = ("standard","special","regular","late","early","on time","generic","rfu");
print join " + ", @r[ grep { $in & (1 << $_) } 0 .. $#r ];
# or
# print join " + ", map { $in & (1<<$_) ? $r[$_] : () } 0 .. $#r;
output
standard + regular + early + generic + rfu | stackexchange-stackoverflow | {
"answer_score": 4,
"question_score": 0,
"tags": "perl, bitmap, binary"
} |
Convert string to timestamp and use timestamp_diff in BigQuery SQL
I have two different strings:
created = `2019-06-30T17:33:09.879350220Z`
updated = `2019-09-25 06:42:45`
I have to perform `TIMESTAMP_DIFF(created_date, updated_date, HOUR)` in a condition.
For the second one, `CAST(updated AS TIMESTAMP)` works but when I do `CAST(created AS TIMESTAMP)`, it shows me an error `Invalid Timestamp`.
How can I cast the created string to a `TIMESTAMP` most efficiently? | Yeah, this format is kinda tricky but works with a format like this:
select parse_timestamp('%Y-%m-%dT%H:%M:%E*SZ','2019-06-30T17:33:09.879350220Z')
returns:
2019-06-30 17:33:09.879350 UTC | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 1,
"tags": "sql, google bigquery, timestamp"
} |
Gimp "Could not interpret PostScript file"
When I try open an `.eps` file in Gimp, I get: `Could not interpret PostScript file '(path to file)'`. I have searched for answers, but all I find is solutions for Windows. They all concerns Ghostscript, which I have installed:
$ ghostscript --version
9.22
I run Ubuntu 18.04 and Gimp 2.10.6. | If you installed Gimp 2.10.6 in Ubuntu 18.04 using the software center, it will be installed as a snap package. Applications installed through snap are contained and are supposed to pack all their own dependencies. A solution at the level of the snap package is probably in the hands of the package maintainer.
To avoid this issue, install Gimp through the regular repositories. The version that comes with Ubuntu 18.04 is the older 2.8 version. You can install a newer version by adding a PPA. | stackexchange-askubuntu | {
"answer_score": 2,
"question_score": 0,
"tags": "gimp"
} |
Checking to see if a variable exists in an array with in_array
I'm using in_array to see if $appid is contained in the variable $r. Here is my print_r of the array $r (the appids in the array are always changing):
$array = array(0 =>
array(0 => 356050, 'appid' => 356050),
1 => array(0 => 338040, ' appid' => 338040),
2 => array(0 => 263920, 'appid' => 263920),
3 => array(0 => 411740, 'appid' => 411740)
);
$appid is equal 263920 which is contained in $r array, yet despite the criteria being met 'it works' is not being echoed. Any help would be appreciated as I don't understand what's flawed about my php statement.
if (in_array($appid, $r)) {
echo 'it works'; // criteria met
} | You have an array containing arrays. The function in_array() looks at the content of the outer array, without recursing into inner arrays. It would find something if you did
if (in_array(array(0 => $appid, 'appid' => $appid), $r) {
echo 'It works';
} | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 1,
"tags": "php, arrays"
} |
How do I align sorting images in table headers to right
Current State
How do I get it right next to header without any spacings ? `<th><img class="waves-effect waves-light" src="../assets/sorting.png" style="text-align: right; padding-right: 0">address</th>` I have tried this but did not help.Any idea on what's going wrong? | Your question is a little unclear, but if you're meaning how to move the sorting images to the right of the th, just move the img to the right of the th.
<th>address<img class="waves-effect waves-light" src="../assets/sorting.png" style="text-align: right; padding-right: 0"></th>
(Obviously I don't have sorting.png for my example, but you get the idea.) | stackexchange-stackoverflow | {
"answer_score": 0,
"question_score": 1,
"tags": "css"
} |
How to calculate the integer coefficients for infinitely many integers $n$, $P(P(n)+1)$ is prime?
The question is: "Calculate all polynomials P with integer coefficients s. t. for infinitely many integers $n$, $P(P(n)+n)$ is a prime."
After using google, I have found proof of contradiction for $P(n)$: Link
My questions are:
1. Do you think that, is it sufficient to find a polynomial which does not fulfill the statement. Is there a famous polynomial for that, what I don't know? Sorry, I am not a mathematician.
2. I posted a line to a contradiction. Can I also adapt that to solve my problem? | If $P(n)=an+b$, then $P(P(n)+1)=P(an+b+1)=a(an+b+1)+b=a^2n+ab+a+b$, so it will represent infinitely many primes if and only if $\gcd(a^2,ab+a+b)=1$, which is the same as $\gcd(a,b)=1$. This settles the case where $P$ is linear. | stackexchange-math | {
"answer_score": 1,
"question_score": 1,
"tags": "polynomials, prime numbers"
} |
How to disable Blazor server side pre-render?
To disable server side pre-render on asp.net core preview 3, you just needed to comment `@(await Html.RenderComponentAsync<MyApp>())`.
Since asp.net core preview 4, when you comment this line, the page doesn't render and on the main component `@page "/"`, the tag `<app>` remains blank.
So, how can we disable server side pre-render ? | Finally found a solution by cores-system in github Source: <
app.UseEndpoints(endpoints =>
{
endpoints.MapBlazorHub().AddComponent<App>(selector: "app");
endpoints.MapFallbackToFile("index.html"); // or - endpoints.MapFallbackToPage("/_Host");
});
Hope this works... | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 4,
"tags": "blazor, blazor server side, asp.net core 3.0"
} |
SourceTree git stash missing
During move of git repository from one hard drive to another my GIT stash broke, or Sourcetree configuration is wrong. From that time my old stashes are not accessible and new one are visible only using GIT Terminal
I can apply stash on my working copy from terminal but it also should be visible in sourcetree sidebar. Any ideas what is wrong and how to fix this?
!enter image description here | Problem with missing stashes was caused by Commodo Antivirus. It was conflicting with whole git background processes. After uninstalling it whole problems with repository and CPU usage disapeared like with a touch of wand. | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 1,
"tags": "git, atlassian sourcetree, git stash"
} |
Any two $1$-forms $\alpha$, $\alpha'$ with property satisfy $\alpha = f\alpha'$ for some smooth nowhere zero function $f$?
This is a followup question to here.
> Let $M$ be a closed $3$-manifold, and let $\xi$ be a $2$-dimensional subbundle of $TM$. Is there a nowhere zero $1$-form $\alpha$ on $M$ with $\alpha(X) = 0$ for any vector field $X$ which is a section of $\xi$?
Does it follow that any two $1$-forms $\alpha$, $\alpha'$ with this property satisfy $\alpha = f\alpha'$ for some smooth nowhere zero function $f$? | Yes. Such a 1-form is the same as a section of $N(\xi)^*$ (as in, a section of $N(\xi)^*$ canonically gives you such a 1-form and vice versa). Equivalently I'm saying "Pick a complementary line bundle; $\alpha$ is determined by its value on that line bundle." By assumption of the existence of your $\alpha$ at all (as in the previous question), the normal bundle is trivial. So sections of it are canonically identified with smooth functions, and your question becomes "Given two nonvanishing smooth functions $\alpha, \alpha'$, is there a smooth function $f$ with $\alpha = f\alpha'$? Of course, the answer is yes: $f=\alpha/\alpha'$. | stackexchange-math | {
"answer_score": 1,
"question_score": 2,
"tags": "general topology, differential geometry, manifolds, differential topology, differential forms"
} |
Create Azure Devops pipeline without code checkout
I have an Azure DevOps pipeline that i use to run scripts for exporting and importing Dynamics solutions between servers. These solution imports/exports dont require any code from a repository. I would like to just run the pipeline without the need to checkout code to speed it up and remove unneccecary steps. Is there a way to do this?
If i am not mistaken, i use the 'classic' versions of pipelines. | You can check the `Don't sync sources` option on the `Get Sources` step:
![enter image description here]( | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 0,
"tags": "azure devops, azure pipelines"
} |
Wouldn't multiple filters in a convolutional layer learn the same parameter during training?
Based from what I have learned, we use multiple filters in a Conv Layer of a CNN to learn different feature detectors. But since these filters are applied similarly (i.e. slided and multiplied to regions of the input), wouldn't they just learn the same parameters during training? Hence the use of multiple filters would be redundant? | I have found the answer to this question: <
It says here: "... (optimization) algorithm finds that loss does not decrease if two filters have similar weights and biases, so it’ll eventually change one of the filter(‘s weights and biases) in order to reduce loss thereby learning a new feature."
Thank you for the answers. Appreciate it :) | stackexchange-stats | {
"answer_score": 8,
"question_score": 16,
"tags": "neural networks, conv neural network, convolution, filter"
} |
upload my project laravel to a shared host
I have a shared hosting service hostinger. as I can upload my laravel 5.2 and configure project?
and I tried using:
namespace App\Providers;
use Illuminate\Support\ServiceProvider;
class AppServiceProvider extends ServiceProvider {
/**
* Bootstrap any application services.
*
* @return void
*/
public function boot() {
//
}
/**
* Register any application services.
*
* @return void
*/
public function register() {
$this->app->bind('path.public', function () {
return base_path() . '/public_html';
});
}
}
but still nothing. | I guess easiest and better approach in this situation will be creating of a symlink between `public_html` and `public` folders. Example for Ubuntu/Debian:
ln -s /path-to-pub/public_html /path-to-pub/public
This solution is better because when you'll decide to move your project to VPN, dedicated server etc., you will not need to remember about any modifications you made and rewrite any code. | stackexchange-stackoverflow | {
"answer_score": 3,
"question_score": 2,
"tags": "php, laravel, web hosting, laravel 5, shared hosting"
} |
how to determine if this integral converge or not?
I should determine whether this is a convergent or divergent integral. The problem is that I don't know how to start. i need to use the comparison test but i don't know where to start. $$ \int_{0}^{1} \frac{e^{-x}}{x}dx $$ | Since $e^{-x}$ is decreasing on $[0,1]$ and positive there, for $0\le x\le1$ you have $e^{-x}/x\ge e^{-1}/x$. Consequently, you can compare with the integral $\int_0^1 {dx\over e\cdot x}$ to show your integral diverges. | stackexchange-math | {
"answer_score": 1,
"question_score": 1,
"tags": "improper integrals"
} |
If for a.e $t \in (0,T)$, $u_n(t,x) \to u(t,x)$ for a.e. $x \in \Omega$,is $u_n \to u$ a.e. in $(0,T)\times\Omega$?
If for almost all $t\in (0,T)$, we have $$u_n(t,x) \to u(t,x) \quad\text{a.e. $x \in \Omega$}$$ does this mean that $$u_n \to u \quad\text{a.e. in $(0,T)\times\Omega$}?$$
Here $\Omega$ is an open domain in $\mathbb{R}^n$. | So you have a measure space $\mathcal{X} = (0,T) \times \Omega$, and the set $$ U = \\{ (t,x) \,:\, u_n(t,x) \not\to u(t,x) \\} \text{,} $$ where for almost all $t$ the slices $$ U_t = \\{x \,:\, u_n(t,x) \not\to u(t,x) \\} $$ have $\mu_{\Omega}(U_t) = 0$.
If $U$ is measurable, you can apply fubini's theorem (assuming that the measured on $(0,T)$ and $\Omega$ are $\sigma$-finite, which holds in particular if they're the usual lebesgue measures) and get $$ \mu_{\mathcal{X}}(U) = \int_{(0,T)} \mu_{\Omega}(U_t) \,d\mu_{(0,T)}(t) = 0 \text{,} $$ so in that case, yes, $u_n(t,x) \to u(t,x)$ a.e. in $(0,T) \times \Omega$.
I don't think you can weaken the measurability requirement on $U$. In particular, it's not sufficient for the measurability of $U$ that all $U_t$ are measurable. Even if you additionally had that all slices $U^x = \\{ t \,:\, u_n(t,x) \not\to u(t,x) \\}$ are measurable, $U$ wouldn't necessarily be measurable I believe. | stackexchange-math | {
"answer_score": 1,
"question_score": 0,
"tags": "measure theory, convergence divergence, almost everywhere"
} |
Adding a USB eject button to the panel/dock
I wish to have a unmounter for my USB Drives. I use docky, and tied the in-built helper, but it displays the internal drives too. But I dont want all the drives, only those on USB.
Can't I have such an "ejecter" in the notification area? | Check out USB Safe Removal application indicator.
!indicator usb screenshot | stackexchange-askubuntu | {
"answer_score": 2,
"question_score": 2,
"tags": "mount, panel, usb drive, docky"
} |
How to access base object from inside method Javascript
I've written a class and this is a snippet taken from it to demonstrate my problem.
<!--language:lang-js-->
var myclass = function () {
this.addItem = function () {
//generateDiv and append..
//generatedeletebtn and append
btn.onclick = this.deleteItem;
}
this.deleteItem = function () {
console.log(this);
}
}
Inside the `deleteItem` function, `this` represents the HTML element clicked. Is there a way I can access the myclass object directly?
I've tried changing `div.onclick = this.deleteItem` to `div.onclick = this.deleteItem(this)` which works as far as accessing the object but the parenthesis invoke the function and remove the items as soon as they're added so that's no good. | This looks like a job for `bind`
btn.onclick = this.deleteItem.bind(this);
You can think of `bind` as wrapping _function A_ referenced by `this.deleteItem` in another _function B_ , which always invokes _A_ with the context given as the first parameter of `bind`.
There is a polyfill available on _MDN_ if you can't assume `bind` is available in your environment. | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 0,
"tags": "javascript"
} |
If two polynomials in a single variable t, agree for all primes t, then they agree as polynomials
I was reading Stanley's enumerative combinatorics V1 and in the 4th proof of proposition 1.3.7 (picture below), he says "if two polynomials in a single variable t (over the complex numbers, say) agree for all $t \in \mathbb{P}$, then they agree as polynomials. Thus it suffices to establish (1.28) for all $t\in \mathbb{P}$".
Why is this? It might be a well-known fact but I am not aware of it. I'll appreciate any response.
 Given hypothesis implies that this difference polynomial takes value zero infinitely often (at the prime numbers). SO the difference has to be constant polynomial zero. | stackexchange-math | {
"answer_score": 3,
"question_score": 0,
"tags": "combinatorics, polynomials"
} |
How to install a specific version of a Sensu plugin using `sensu-install`?
In order to prevent that the latest version of a plugin will break the Production monitoring it should be possible to install a specific version:
**Attempt**
[user@host ~]$ sensu-install --help
Usage: sensu-install [options]
-h, --help Display this message
-v, --verbose Enable verbose logging
-p, --plugin PLUGIN Install a Sensu PLUGIN
-P, --plugins PLUGIN[,PLUGIN] PLUGIN or comma-delimited list of Sensu plugins to install
-s, --source SOURCE Install Sensu plugins from a custom SOURCE | It is possible to specify a `plugin version` while installing using `sensu-install`, e.g:
sensu-install -p sensu-plugins-disk-checks:2.0.1
Or if you want to install multiple plugins with version (note capital -P)
sensu-install -P sensu-plugins-disk-checks:2.0.1,sensu-plugins-memory-checks:1.0.2
Reference: #use-sensu-install-to-install-sensu-plugins | stackexchange-serverfault | {
"answer_score": 1,
"question_score": 0,
"tags": "sensu"
} |
How to use class ContentQueryMap to cache Cursor values?
I read that ContentQueryMap can be used to access Cursor values not to access the db everytime.
But, how to use it? The Official Android help is hermetic... | ContentQueryMap mQueryMap = new ContentQueryMap(cursor, BaseColumns._ID, true, null);
Comparator<Long> numberAmaxB = new Comparator<Long>() {
@Override public int compare(Long s1, Long s2) {
if (s1<s2)
return 1;
else if (s1>s2)
return -1;
else
return 0;
}
};
SortedMap<Long, String> mySortedMap = new TreeMap<Long, String>(numberAmaxB);
for (Map.Entry<String, ContentValues> row : mQueryMap.getRows().entrySet()) {
Long _ID = Long.valueOf(row.getKey());
String data= row.getValue().getAsString("data_column");
conversationsSortedMap.put(_ID, data);
} | stackexchange-stackoverflow | {
"answer_score": 0,
"question_score": 1,
"tags": "android, caching, cursor"
} |
Objects in Fragment get destroyed when Fragment is destroyed?
Are objects in Fragment get destroyed when Fragment it is in gets destroyed? I.e. when onDestroy() is called. | Having `onDestroy()` called on your Fragment doesn’t mean that it will be cleared from memory right away. More than that if you keep a reference to it then it won’t be garbage collected at all. But when there’s no references left at some point in time the fragment will be removed (no guarantees when exactly that happens - but usually it’s indeed soon after `onDestroy()`).
All the objects in your fragment will be garbage collected after the fragment is garbage collected if you have no other references to them. | stackexchange-stackoverflow | {
"answer_score": 0,
"question_score": -2,
"tags": "android, fragment, android ondestroy"
} |
TaskDialog default button
stackoverflow just works faster :)
I'm using the Windows® API Code Pack for Microsoft® .NET Framework to access Windows 7 API and I want to change my old MessageBox to TaskDialog.aspx). One thing I cannot find is the default button of the dialog. Is there a way to set it? what about a work around?
thanks | There is a Default property on a control under the taskbased dialog you can set to true. From the sample (Samples\TaskDialogDemo\CS\TaskDialogDemo) that ships with it:
TaskDialog tdEnableDisable = new TaskDialog();
tdEnableDisable.Cancelable = true;
tdEnableDisable.Caption = "Enable/Disable Sample";
tdEnableDisable.InstructionText = "Click on the buttons to enable or disable the radiobutton.";
enableButton = new TaskDialogButton("enableButton", "Enable");
enableButton.Default = true;
enableButton.Click += new EventHandler(enableButton_Click);
If you run the demo, click Enable/Disable sample and then press Enter a few times you will see that the two buttons take turns being the default. | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 1,
"tags": "windows 7, messagebox, taskdialog, windows api code pack"
} |
declaring local OpenCV Mat variable as static for preventing reallocation
Several functions in a C++ OpenCV project I am working on use local Mat (and UMat) variables as temporary buffers for internal computations.
I would like to prevent these functions to allocate memory for all their local Mat variables every time they are called. The purpose of this is not to use less memory, but to make sure memory is available or fail at the first call and to prevent any possible overhead due to memory allocation.
To prevent reallocations, I thought about declaring the local Mat variables as static and making sure they will always store the same data size and type within the functions, despite I do not care about carrying the data they store across multiple calls.
Does this approach make sense? Am I doing it the wrong way, or is there a better/safer one? | From personal experience, an approach of reusing temporary `cv::Mat` objects in repeated iterations is a useful and sensible approach.
One significant benefit is avoiding the constant reallocation of relatively large arrays, which tends to carry a noticeable overhead. Furthermore, at least on 32bit platforms, it helps to limit address space fragmentation (which becomes noticeable when your program runs for a long time).
However, I wouldn't use static variables, since that will generally reduce the reusability of your code (especially when you want to take advantage of parallelization). This Q/A will provide some additional explanation on why that is the case.
You could either provide reference(s) to the persistent context as a parameter, or perhaps implement something like a functor, or just use member variables in your class... | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 1,
"tags": "c++, opencv, memory management, static"
} |
How to pass text to a search box via Selenium
I am trying to send a query to google translate using selenium. However I am finding difficult to find the class in order to pass arguments to the search box.
I have written the following:
chrome_options = webdriver.ChromeOptions()
driver = webdriver.Chrome('/chromedriver')
driver.get('
query='Text to translate'
search = driver.find_element_by_name('q') # <- this is wrong!
search.send_keys(query)
search.submit()
Could you please point to the right class or argument to pass in my code? Thanks | This works for me:
from selenium import webdriver
chrome_options = webdriver.ChromeOptions('/chromedriver')
driver = webdriver.Chrome()
driver.get('
query = 'Text to translate'
search = driver.find_element_by_css_selector('#source')
search.send_keys(query)
All I did was inspect the text area, and instead of `find_element_by_name` I used `find_element_by_css_selector`, so I copied the css selector of the text area. Also, you don't have to submit as it translates automatically. | stackexchange-stackoverflow | {
"answer_score": 0,
"question_score": 0,
"tags": "python, selenium, web scraping, selenium chromedriver"
} |
Good way to remove something from a bathroom sink overflow drain?
My wife dropped an earring down the overflow drain of her bathroom sink. The earring is about 1" in diameter, so the hole which goes from the overflow to the main drain is too small for it to pass through.
The earring is silver, so it's non-magnetic (I checked the other one to make sure).
Short of removing the sink and turning it upside-down, any other ideas on getting that thing out? I thought of just a hook and wire, but it would be a crapshoot on being able to hook it.
Just want to add, here's what the sink looks like. Note that the overflow drain is very narrow, and if you measured between the opening and the back of it, it's maybe 5/8":
![enter image description here]( | I'd be going at it with a strongest vacuum you can come up with. Maybe put a nylon stocking over the end of the hose so the earring doesn't get damaged flying down the pipe. | stackexchange-diy | {
"answer_score": 74,
"question_score": 30,
"tags": "drain, sink"
} |
Making a function that will identify an infinite loop in existing code
I'm trying to create a function that will identify if the code in a python file will go through and infinite loop or not. This is what I have so far:
def reader(filename):
myfile = open(filename)
counter = 0
#counters the number of lines in the file
for line in myfile:
counter +=1
print line
#print number of lines in file
print counter
#execute the code in file
execution = execfile(filename)
What I'm trying to do is execute the file, and maybe try to count how many lines are executed and compare that to whatever number in the previous counter. For example, if the counter > lines_exected, then return True, there is an infinite loop in code. Would this work? Or would I have to try something else? | This is impossible. Read up on the halting problem.
Also, even if it were possible in theory, or even if you just want to do some sort of heuristic guess, you obviously can't do it by just running the file. If the program has an infinite loop, you will run the infinite loop and get stuck in it, so you'll never get a chance to check your counter. | stackexchange-stackoverflow | {
"answer_score": 8,
"question_score": 2,
"tags": "python, infinite loop, halting problem"
} |
How do I quickly position two windows side by side?
Sometimes you need to see two windows side by side, e.g. when following instructions or when working on a translation. How do I quickly arrange two windows like that?
**edit:** interested in answers for all platforms and window managers | There are good solutions for both Mac and Windows that I know of:
## Windows 7
This feature is built in, and it's called **Aero Snap**. You can use the following keyboard shortcuts to get the behavior you want:
* `Win` \+ `←` moves the current window to the left half of the screen.
* `Win` \+ `→` moves the current window to the right half of the screen.
* `Win` \+ `↑` maximes the current window.
## Windows XP and Vista
GridMove allows you to setup regions to snap windows to via a shortcut key. I mapped `Win` \+ `1` to move a window to the left half of the screen and `Win` \+ `2` to use the right half.
AeroSnap makes Windows 7's native keyboard shortcuts available in Windows Vista and Windows XP.
## Mac OS X
Cinch, SizeUp (both unlimited free trials) and TwoUp (discontinued - available here) from Irradiated Software all accomplish this task perfectly. SizeUp adds some extra features, including multiple monitor support. | stackexchange-superuser | {
"answer_score": 36,
"question_score": 28,
"tags": "window manager"
} |
Customizing Slick Generator
I'm using the Slick generator to generate my tabble definitions based on my database and I would like to change a thing in the generated code. When it generates the classes it does not put my auto increment keys as Option[Int] = None in the case classes... Is there a way to do that? And maybe add an autoinc method in the table definition that returns the generated id like this for example:
def autoInc = id.? ~ name <> (User, User.unapply _) returning id | The code generator already supports this. You have to set `autoIncLastAsOption = true`.
new SourceCodeGenerator(model){
override def Table = new Table(_){
override def autoIncLastAsOption = true
}
}
Also see < for more help with customizing the code generator. | stackexchange-stackoverflow | {
"answer_score": 3,
"question_score": 0,
"tags": "scala, slick"
} |
Is $\pm\infty$ the only case for one-sided limits to not exist?
Could one-sided limits not exist but not equal to $\pm\infty$
e.g. $\displaystyle \lim_{x->c^+}f(x)$ DNE and $\displaystyle \lim_{x->c^+}f(x)\neq\pm\infty$ | Yes.
Consider the function $$f(x)= \sin(1/x)$$ on the interval $(0,1).$
$$ \lim_{x\to {0^+}} f(x)$$ does not exist due to oscillations and the function is bounded. | stackexchange-math | {
"answer_score": 3,
"question_score": 0,
"tags": "calculus, limits"
} |
Reasons behind naming in easy-to-confuse Python's classes such as OS and SYS?
I have noticed that considerably amount of questions in SO, relating to Python, are about people messing up Sys -class, OS class and no class. For example, an easy confusing is the case: `os.open("something")`, `open("something")` and `sys.open("something")`. I haven't understood yet the reasons behind the naming of classes, perhaps it is just an evolution.
1. I would like to hear `why` they were created with their current names?
2. Are naming due to things like having FDs in a class?
3. Is naming because some classes require special privileges?
4. To which extent is the naming a design solution?
If you cannot answer the question, feel free to suggest some good mnemonics to memorize the classes and to differentiate them. | Built-in functions are things that you need often. You do not have to import any module to access them, and thus don't use any module prefix either. `open()` is one such function, since opening files is a very common operation. It opens a file and returns a file object, which is easy to use.
The `os` module is for operating system interfaces. `os.open()` is a raw interface to the file interface of the operating system. It opens a file and returns the bare file descriptor, which you do not normally need for anything.
The `sys` module is for system-specific things. `sys.open()` does not exist. | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 3,
"tags": "python, security, operating system, naming, language history"
} |
What is the most "space effective" way to store text in MySQL?
I have +10 million articles(200 to 1000 words) in a `InnoDB` table. I only use this type of query when I'm working with `article` field:
SELECT article,title,other_fields from table where id=123;
**What is the most "space effective" way to store text in MySQL?**
Now the **table size is _say_ 100GB, my objective is to make that as little as possible** without causing too much performance tradeoff. | MyISAM is more space friendly than InnoDB, you can start with that one. | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 3,
"tags": "mysql, sql, optimization"
} |
Any space $X$ can be embedded as a dense subset of a Lindelöf space.
I have the following statement to prove, but I'm not sure how to go about doing so.
> Any space $X$ can be embedded as a dense subset of a Lindelöf space.
There is a hint associated to this exercise,
[ _Hint:_ Adjoin a point $p$ to $X$ whose nbhds are the sets $\\{p\\}\cup E$, where $E$ is a subset of $X$ whose complement in $X$ is Lindelöf.] | The hint gives the game away, but there is one subtlety:
Define $Y = X \cup \\{p\\}$ as sets, where $p = \infty$ or any point not in $X$. Let $\mathcal{L}$ be the set of all **closed** subsets of $X$ that are Lindelöf (in the subspace topology).
Let $\mathcal{T}_Y$ be the topology with subbase $$\\{\\{p\\} \cup E\mid X\setminus E \in \mathcal{L}\\} \cup \mathcal{T}_X$$
and note that $i: X \to Y$ defined by $i(x)=x$ is an embedding and $Y$ is Lindelöf (taking any open cover, of $Y$ consider first what the open set containing $p$ is etc.; it's similar to the one-point compactification that way).
$X$ (rather, its topological copy $i[X]$) will only be dense in $Y$ if $X$ is not itself Lindelöf, but we can assume that WLOG anyway. | stackexchange-math | {
"answer_score": 1,
"question_score": 0,
"tags": "general topology"
} |
compass watch ERROR
I am trying to use Sass with Compass on my static HTML project. This is what I did:
$ gem install compass
$ cd <myproject>
$ compass install compass
it created following:
directory ./sass/
directory ./stylesheets/
create ./sass/screen.scss
create ./sass/print.scss
create ./sass/ie.scss
create ./stylesheets/screen.css
create ./stylesheets/ie.css
create ./stylesheets/print.css
Then, I start watching scss `compass watch sass:stylesheets`, I get an error:
error sass:stylesheets (/var/lib/gems/2.3.0/gems/sass-3.4.23/lib/sass/plugin/compiler.rb:484:in `read': No such file or directory @ rb_sysopen - /home/pc/test/webproj/sass:stylesheets)
Please help!! | Skimming through the reference it seems that `watch` command is expecting a path to directory. So, your command should be:
compass watch sass/stylesheets | stackexchange-stackoverflow | {
"answer_score": 0,
"question_score": 0,
"tags": "ruby, sass, rubygems, compass"
} |
Hex literal syntax for literals in webassembly (wast)
Webassembly: I cannot find a reference for this syntax `(f32.const -0x0p+0)`. What number / bit pattern does it represent? It is from a test file for the reference interpreter:
< | It’s hexadecimal floating-point as supported by C and more recently C++.
The significand is given in hexadecimal, and the exponent is given in decimal and interpreted with respect to base 2. It can exactly represent all floating-point numbers except NaNs.
The text format adopted this in this issue. | stackexchange-stackoverflow | {
"answer_score": 3,
"question_score": 4,
"tags": "webassembly"
} |
Match string between two other different strings
Another regex question:
I'd like to capture text that exists between two different marker strings. The thing is, the marker strings have a few options. For example:
I'm very hungry **for a sandwich** and tomorrow I'll go to the store - capturing between "I'm very hungry" and "and"
I'm very tired **so I'll go to sleep**. - capturing between "I'm very tired" and ".".
I'm coding in Javascript, and I thought:
/string one(.*?)string two|\.|string three|string four/gi
But that doesn't seem to work. It just grabs between `string one` and `string two` ignoring `string three` and `string four`.
What am I doing wrong with the regex? | maybe you need to group strings because `|` has low precedence
/string one(.*?)(?:string two|\.|string three|string four)/gi
Edit: adding parentheses changes precedence because the expression in parentheses is evaluated before the rest of the expression. In addition, here we use non-capturing groups because we use the `(?:` syntax. | stackexchange-stackoverflow | {
"answer_score": 3,
"question_score": 0,
"tags": "javascript, regex"
} |
Better way to get a list of files in a given directory
When I need to work with files in a given directory, I always resort to the following way, which to my opinion is cumbersome:
this_dir = Dir.pwd
filepath = File.join(this_dir, "directory")
file_list = Dir[File.join(filepath, "*.txt")]
I know that the code below returns an array of filenames. Supposedly there is only one file in that directory, the way I'm used to reaching to is:
File.basename(file_list[0])
Are there better and tidier ways to get a list of files in a directory, so that I can do whatever I want with these? | There's some things to note here. In many cases file operations are _presumed_ to work based on your current working directory, `Dir.pwd`, so that does not need to be specified.
The easiest way to find the first matching file is:
Dir['directory/*.txt'].first
There's not much to be gained here over your `file_list` approach, except that you don't need all the preamble. | stackexchange-stackoverflow | {
"answer_score": 6,
"question_score": 3,
"tags": "ruby"
} |
db2 import csv with null date
I run this
db2 "IMPORT FROM C:\my.csv OF DEL MODIFIED BY COLDEL, LOBSINFILE DATEFORMAT=\"D/MM/YYYY\" SKIPCOUNT 1 REPLACE INTO scratch.table_name"
However some of my rows have a empty date field so I get this error
SQL3191N which begins with """" does not match the user specified DATEFORMAT, TIMEFORMAT, or TIMESTAMPFORMAT. The row will be rejected.
My CSV file looks like this
"XX","25/10/1985"
"YY",""
"ZZ","25/10/1985"
I realise if I insert charater instead of a blank string I could use **NULL INDICATORS** paramater. However I do not have access to change the CSV file. Is there a way to ignore import a blank string as a null? | This is an error in your input file. DB2 differentiates between a NULL and a zero-length string. If you need to have NULL dates, a NULL would have no quotes at all, like:
"AA",
If you can't change the format of the input file, you have 2 options:
* Insert your data into a staging table (changing the DATE column to a char) and then using SQL to populate the ultimate target table
* Write a program to parse ("fix") the input file and then import the resulting fixed data. You can often do this without having to write the entire file out to disk – your program could write to a named pipe, and the DB2 IMPORT (and LOAD) utility is capable of reading from named pipes. | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 0,
"tags": "db2"
} |
JNA UnsatisfiedLinkError exception
I am trying to deploy my application that invokes native calls using JNA library, but I get the following exception. Exception in thread "main" java.lang.UnsatisfiedLinkError: Unable to load library 'myCustomDLL': Native library (win32-x86-64/myCustomDLL.dll) not found in resource path ([myproject/target/classes/, ...some jars...])
What do I need to do in order to invoke the function correctly?
Any help much appreciated | Actually I found the answer to this. Basically, I needed to install Microsoft Visual C++ Redistributable package to install all the necessary DLLs needed for JNA to work. Thanks for other responses to this question. | stackexchange-stackoverflow | {
"answer_score": 0,
"question_score": 0,
"tags": "java, java native interface, jna"
} |
Defining Swift functions that operate on Types instead of values
In Swift, the `?` operator takes `Types` as parameters, instead of values:
var z = 42? // won't create an Optional<Int> and won't compile
var z : Int? = 42 // ? takes Int and give a Optional<Int>
How can I create my own functions, or operators that work on Type instead of values? | What you want to achieve is not possible.
However there is a workaround: you can create a custom operator that given a literal or variable, converts it to an optional. Swift doesn't allow using the `?` character in custom operators, I am choosing a random combination, but feel free to use your own:
postfix operator >! {}
postfix func >! <T>(value: T) -> T? {
return value as T?
}
Once done, you can use it as follows (output from playground):
10>! // {Some 10}
"Test">! // {Some "Test"} | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 1,
"tags": "types, swift, option type, type variables"
} |
Why Tulsi water is provided as theertha in temples?
As we all know, in Hindu Temples, after the Mangalarti has been done, priest will start serving the theertha which is a Tulsi water. Why is it served in all the temples? Also sometimes they serve milk and fruit mixtures. | It is not used in ganesha temple, since ganesha and tulsi have a bad history. But It is used with every pooja to other gods like without tulsi leaves no prasad(holy food sacrifice) is complete, and the water that is kept in front of god in temple and is seen as their drinking water.It is distributed as prasada like holy water to every person after aarti.
And yes there is a scientific and medical reason for this , tulsi provide relif from congestion, mixing it in water and drinking it balance kapha in body, which is very crucial for curing many diseases and it is also said that kahpha (cough) blocks prana channels and causes different problems.More info | stackexchange-hinduism | {
"answer_score": 1,
"question_score": 1,
"tags": "temple, practice, tulasi"
} |
Progress spinner inside textview or autocompletetextview
I would like to create autocompletetextview with loading spinner inside (like in bilt-in Android browser, when page is loaging).
How can I implement it?
Also is it existing drawable inside android framework? | Well you could use a FrameLayout for the spinner, then add padding to get it in the right position. Look here | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 1,
"tags": "android"
} |
RedBeanPHP передать ORDER BY в качестве параметра
Здравствуйте
есть вот такой запрос:
$content = R::findAll('team', 'ORDER BY ? ', [$sort]);
если распечатать запрос получим вот такой результат:
SELECT `team`.* FROM `team` ORDER BY 'date DESC' -- keep-cache
resultset: 8 rows
Как видим сортировка записей идет по `date DESC` но сортировка НЕ происходит
Подскажите пожалуйста в чем дело!? | Просто попробуйте следующий вариант, сначала формируем строку $params
$params = ' ORDER BY ' . $column . ' ' . $sort;
$content = R::findAll('team', params );
// Мне вот этот код помог $user_stories = R::findLike( 'story', ['us_id' => [ $id ]], ' ORDER BY id DESC ' ); Story - название таблицы, Us_id - Столбец, по которому ищу, Id - тот id, который идентифицирует ORDER BY id DESC - Выкладывает содержимое по id в обратном порядке.
Потом через цикл foreach можно все вывести. Надеюсь, я тебе помог) Ответ нашел в документации у Redbeanphp) < | stackexchange-ru_stackoverflow | {
"answer_score": 0,
"question_score": 2,
"tags": "mysql, redbeanphp"
} |
How to get the previous word with regex?
I have a path like this one:
C:\Development.TFS\Examn\R4-branch\Web\OrganisationManager\themes\blue\css
And I need a regex to get the word "blue" out of there. I tried, but didn't find a solution yet. It's practically getting the word before the last word from that string. Please help, thank you | (\w+)\W+\w+$
matches the second-to-last word, captures it into backreference no. 1, then matches one or more non-word characters, then the last word and then EOL.
If you don't really want actual words but path elements to match (even if they contain non-word characters), then
([^\\:]+)\\[^\\]+$
might do a better job.
Edit: Added a `:` to the "second-to-last-word group" so the regex can handle relative paths, too. | stackexchange-stackoverflow | {
"answer_score": 6,
"question_score": 3,
"tags": "regex, word"
} |
Volume of solid of revolution with Disk and Tube method for bounded region
I have a region bounded by y axis and the curves of equation $y=\sqrt{x}$ and $y=(x-2)^2$
I need to evaluate the volume of the solid of revolution with integral but with some restriction.
First, I need to evaluate when rotating this region around the x axis using the **DISK** method.
Second, I need to evaluate when rotating around the line $x=2$ using the **CYLINDER** method.
I'd like to understand how to determinate the integral for both method, not the answer just a start...
I know that for the disk method You need to get the volume of a disk $\pi R^2E$ But I'm not sure how to define the integral considering the rotation of the region.
As for the tube method, I know the equation is $2 \pi xy \delta x $ but I can't go further... | Draw a reasonably careful picture. The relevant point of intersection of the two curves is at $x=1$. The region we are rotating is crudely speaking triangular, one corner the origin, then the next corner $(1,1)$, and the final corner at $(0,4)$. The left side of the region is the straight line segment from $(0,0)$ to $(0,4)$, Now that we have the region firmly in hand, the rest is not difficult.
**First:** The curve "above" here is $y=(x-2)^2$, the curve below is $y=\sqrt{x}$. If we take a slice perpendicular to the $x$-axis at $x$, we get a cross-section which is a circle of radius $(x-2)^2$, with a circular hole of radius $\sqrt{x}$. I will leave it at that, since you wanted a start and not a full solution.
**Second:** The radius of the shell "at" $x$ is $2-x$. The height of the cylinder (tube) is $(x-2)^2-\sqrt{x}$. | stackexchange-math | {
"answer_score": 1,
"question_score": 1,
"tags": "integration, definite integrals, volume"
} |
Flask app return string doesn't display <abc>
I tried to display a string on a webpage with this Flask code:
@app.route('/')
def index():
return 'Variable can be of different types: string and <int>'
and got
Variable can be of different types: string and
without "<>". A way to fix it is to add a space between "<" and "int" like:
Variable can be of different types: string and < int >.
Also I noticed that the space for the closing > as in "< int>" doesn't matter.
Other characters such as [int] and {int} have no such a problem. Why? tag related? | Yes, it is tags related, it gonna be shows up like this
 or greater than (>) signs in your text, the browser might mix them with tags.
However, if you want to still display that, you can just do this ![enter image description here](
For more reference, here | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 1,
"tags": "html, flask, tags"
} |
Making phonegap application that reads pages from web site
I would like to create a 'shell' phonegap application which displays content from another web site. For example, I want to get content from our existing intranet and display it within a deployed phonegap application. Is this possible?
(so when a user hits a link on the page, it just navigates within the shell to the next page). I guess this would be like using phonegap as an iframe in a regular browser.
Is this possible? (reason: we have existing intranet and need to make accessible via phonegap application) | yes it's possible, just do an ajax call on the website and put the data into the html elements in your phone gap app. | stackexchange-stackoverflow | {
"answer_score": 0,
"question_score": 0,
"tags": "cordova"
} |
Saving pyqgis QgsGeometryAnalyzer.dissolve output in memory?
How to save pyqgis QgsGeometryAnalyzer.dissolve output in memory (temporal layer)?
Usage example:
from qgis.analysis import *
shp_path = "C:\shape_file.shp"
QgsGeometryAnalyzer().dissolve(layer, shp_path, onlySelectedFeatures=False, uniqueIdField=-1) | These algorithms are old and unmaintained. They can produce only shapefiles. They have been dropped in QGIS 3 in favor of the Processing framework, in which you can select the output format.
So you should better not use this class in QGIS 2 and move now to Processing, it will be easier when you will move to QGIS 3.
import processing
processing.alglist('dissolve')
Dissolve--------------------------------------------->qgis:dissolve
v.dissolve - Dissolves boundaries between adjacent areas sharing a common category number or attribute.--->grass7:v.dissolve
How to use Processing from Python < | stackexchange-gis | {
"answer_score": 2,
"question_score": 1,
"tags": "pyqgis, in memory"
} |
Understanding the Schwarz reflection principle
I am currently reading Stein and Shakarchi's Complex Analysis, and I think there is something I am not quite understanding about the Schwarz reflection principle. Here is my problem:
Suppose $f$ is a holomorphic function on $\Omega^+$ (an open subset of the upper complex plane) that extends continuously to $I$ (a subset of $\mathbb{R}$). Let $\Omega^-$ be the reflection of $\Omega^+$ across the real axis.
Take $F(z) = f(z)$ if $z \in \Omega^+$ and $F(z) = f(\overline{z})$ is $z \in \Omega^-$. We can extend $F$ continuously to $I$. Why isn't the function $F$ holomorphic on $\Omega^+ \cup I \cup \Omega^-$?
I think there's some detail of a proof that I overlooked. My intuition tells me that $F$ isn't holomorphic for the same reason that a function defined on $\mathbb{R}^+$ isn't necessarily differentiable at zero if you extend it to be an even function. | $f(\bar{z})$ is not holomorphic (unless $f$ is constant), as $d(f(\bar{z}))=f'(\bar{z}) d\bar{z}$ is not a multiple of $dz$ (but rather of $d\bar{z}$). Perhaps more intuitively: holomorphic = conformal and orientation-preserving; $f(\bar{z})$ is conformal, but changes the orientation (due to the reflection $z\mapsto\bar{z}$). Hence your function $F$ is not holomorphic on $\Omega^-$.
On the other hand, $\overline{f(\bar{z})}$ is holomorphic, as there are two reflections. If $f$ is real on $I$ then by gluing $f(z)$ on $\Omega^+$ with $\overline{f(\bar{z})}$ on $\Omega^-$ you get a function continuous on $\Omega^+\cup I\cup\Omega^-$ and holomorphic on $\Omega^+\cup\Omega^-$. It is then holomorphic on $\Omega^+\cup I\cup\Omega^-$ e.g. by Morera theorem. | stackexchange-math | {
"answer_score": 8,
"question_score": 9,
"tags": "complex analysis"
} |
show div only if meta tag exists
I have an include file that is used in different applications and different platforms.
I want to show a div below
<div id="my-menu" class="dropdown"></div>
only if there is a meta tag - its hidden via `display:none` by default in the css
the meta tag would be something like this
<meta name="login-menu" content="show"/>
if they add the above meta on their applications i want show `#my-menu` div.
what is the best way to do this via jquery?, here is a start
if ($('meta[name="login-menu"]').attr('content')) {
$( "#my-menu" ).show();
} | You should check the length to see if it exists:
if ($('meta[name="login-menu"]').length) {
$( "#my-menu" ).show();
} | stackexchange-stackoverflow | {
"answer_score": 3,
"question_score": 0,
"tags": "javascript, jquery, meta"
} |
Javascript hashing algorithm
I'm trying to learn how to do some basic hashing in Javascript and I've come across the following algorithm:
var hash = 0;
for (i = 0; i < this.length; i++) {
char = str.charCodeAt(i);
hash = ((hash<<5)-hash)+char;
hash = hash & hash;
}
I don't really understand how it works and I was hoping you could help me out. In particular I don't understand `(hash<<5)-hash` and `hash = hash & hash`. Thank you for your replies.
**Note:** For anyone looking for the source, it's an implementation of Java’s String.hashCode(): < | The step
hash = ((hash << 5) - hash) + char;
is effectively:
hash = ((hash * 32) - hash) + char;
Then,
hash = hash & hash;
will only change the value if the number has overflowed the integer range (32 bits, or maybe 31). (I wouldn't do it that way but it's a matter of style.)
In that code, the variables "i" and "char" should be declared:
var hash = 0, i, char; | stackexchange-stackoverflow | {
"answer_score": 3,
"question_score": 3,
"tags": "javascript, algorithm, string hashing"
} |
Why is my Javascript not working?
This is my Javascript:
<script type="text/javascript">
function contactChange() {
var contact = document.getElementbyId("contact");
if (contact.style.display == "none") {
contact.style.display = "block";
} else {
contact.style.display = "none";
}
}
</script>
And here is my site:
< | It's `document.getElementById`, not `document.getElementbyId`. (In JS, name of variables and functions are case-sensitive)
Debugging tip : Look at the JS console (F12 in Google Chrome and IE9, Ctrl+Shift+K in Firefox). In this case, following error can be seen:
!Debugging console in Google chrome
It shows where the error happened (line 260 in your HTML/JS code) and what the error is(Object `#<HTMLDocument>` has no method `getElementbyId`). | stackexchange-stackoverflow | {
"answer_score": 18,
"question_score": 3,
"tags": "javascript, html"
} |
Adding What's this button
How can i add what's this button besides close button, i have seen lot of threads where they want to remove it, but not a single thread where they want to add it. From couple of threads they mentioned it was default, well it isn't default in mine and I am using windows. This is how my title bar looks. ;
Note that you will be missing out the maximize and the minimize buttons when you do this. According to Microsoft's documentation:
> WS_EX_CONTEXTHELP cannot be used with the WS_MAXIMIZEBOX or WS_MINIMIZEBOX styles.
These are the underlying windows system flags for `Qt::WindowContextHelpButtonHint`, `Qt::WindowMinimizeButtonHint` and `Qt::WindowMaximizeButtonHint`. | stackexchange-stackoverflow | {
"answer_score": 3,
"question_score": 4,
"tags": "c++, qt"
} |
Can I run a script on my Pi and keep it running when I close SSH?
I have a Raspberry Pi running Debian Lite (terminal only, no desktop). I've installed Node.js and am currently running a script by making an SSH connection through puTTY.
The problem is, when I close the puTTY window the script stops running. I need it to run when my desktop is turned off, otherwise having it on the Pi is pointless.
So far I have tried: -Nohup | Appended the output but still stopped running when I closed the terminal. | Multiple options:
Install `screen` or `tmux` on the PI and start the job with those programs.
(or) Run the job with the `nohup` command:
nohup command
(or) Run the job in the background and use `disown`:
command &
disown %1
I recommend option 1. | stackexchange-stackoverflow | {
"answer_score": 3,
"question_score": 1,
"tags": "node.js, raspberry pi"
} |
Facebook app POST displays blank page
I'm programming a Facebook app on localhost. When some event triggers, the user gets a notification on Facebook. The notification works great, but however when he opens it, it sends a POST request to:
`
and displays like this in the browser:
`
If the user is located outside the app on Facebook (but on Facebook), the app loads correctly. If the user refreshes the page while in the app, it displays correctly. However when the user is located INSIDE the app and clicks the notification, it displays a white blank page.
What could be causing this?
I'm using ASP.NET MVC 4 .NET framework 4.5 and yes, my Messages controller function is POST. | I got this fixed by changing the apps `Namespace` to something other than blank. Now it works. | stackexchange-stackoverflow | {
"answer_score": 0,
"question_score": 0,
"tags": "facebook, asp.net mvc 4, http post, .net 4.5"
} |
How can I make QtCreator compile with gsl library?
I am trying to use the GNU Scientific Library (GSL) < in QtCreator. How can I tell Qt creator to add these flags: < to link correctly? | You need to edit your .pro file and add the extra libs by hand, e.g.:
LIBS += -L/usr/local/lib example.o -lgsl -lgslcblas -lm
See the QMake documentation for more information. | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 1,
"tags": "c++, linux, qt creator, gsl"
} |
C# / SQL Error: There was an error parsing the query. [ Token line number = 1,Token line offset = 26,Token in error = user ]
I can't my mind around this error. The server error point out towards this line:
<select name="selectUserName">
@foreach(var row in db.Query(selectQueryString)) {
<option>@row.username</option>
}
</select>
where `selectQueryString` is defined as:
var selectQueryString = "SELECT ID, username FROM user"; | User is a reserved word in SQL Server. Try:
FROM [User] | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 2,
"tags": "c#, sql, razor"
} |
Wie sagt man " to shed light onto sth" auf Deutsch?
> Ich brauche Hilfe bei der deutschen Präpositionen. Du kannst wahrscheinlich Aufschluß über diesem Problem geben.
I need help with german prepositions. You can probably shed a light on this problem. | > Licht ins Dunkel bringen
Example:
> Wir kamen lange nicht weiter, aber dann kam unser Chef und hat Licht ins Dunkel gebracht. Endlich konnten wir das Problem lösen.
Translated:
> We were stuck, but then came our boss, he shed some light (onto the problem). Finally we were able to solve the problem. | stackexchange-german | {
"answer_score": 3,
"question_score": 1,
"tags": "grammar, verb choice"
} |
removing item from array after match
I have
var a =[1 , 2, 3, 4, 5]
var b = [2, 3]
Now I want to remove b from a using inArray
if($.inArray(b, a) === 1)
a.remove(b);
is this right ? cause when i console a , it hasnt changed | Try this this may help you
function arr_diff(a1, a2)
{
var a=[], diff=[];
for(var i=0;i<a1.length;i++)
a[a1[i]]=true;
for(var i=0;i<a2.length;i++)
if(a[a2[i]]) delete a[a2[i]];
else a[a2[i]]=true;
for(var k in a)
diff.push(k);
return diff;
}
var a = [1,2,3,4,5,6]
var b = [2,3]
console.log(arr_diff(a,b)); | stackexchange-stackoverflow | {
"answer_score": 3,
"question_score": 1,
"tags": "javascript, jquery, arrays"
} |
why func() and func(void) are different
I have a function, can write in 2 ways.
void function(void) {
// operations....
}
and
void function() {
// operations......
}
Both functions are of same prototype. Why we have to mention `void` as argument at function definition? | No, both have different prototypes.
Compile the below programs you will understand.
void function1(void)
{
printf("In function1\n");
}
void function2()
{
printf("In function2\n");
}
int main()
{
function1();
function2(100); //Won't produce any error
return 0;
}
Program 2:
#include <stdio.h>
void function1(void)
{
printf("In function1\n");
}
void function2()
{
printf("In function2\n");
}
int main()
{
function1(100); //produces an error
function2();
return 0;
} | stackexchange-stackoverflow | {
"answer_score": 10,
"question_score": 3,
"tags": "c, function"
} |
Why do functions defined in a loop all return the same value?
I'm confused by the following JavaScript code. I wrote a loop and defined a function inside the loop, but when I call a function defined in the loop, I only get 10 rather than the index.
Obviously, in the following code I abstracted out stuff that isn't relevant:
objectArray = [];
for (i = 0; i< 10; i++){
objectArray[i] = {};
}
for (i = 0; i< 10; i++){
objectArray[i].get_number = function(){
return i;
}
}
console.log(objectArray[5].get_number()); // returns 10 rather than 5
I always get 10 rather than i as expected. | It's because of JavaScript closure. The method `objectArray[i].get_number` has direct access to `i` (not a copy of `i`). The value of `i` lives on in memory because each method `objectArray[i].get_number` still has access to it. There's only one `i`, and when the loop iterates it, it increases by one. When a method `objectArray[i].get_number` accesses it, the loop has already run to completion, so it accesses the final value of `i`. | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 2,
"tags": "javascript"
} |
Change Android home screen page programmatically
Here is the sample code which creates some specified shortcuts on the Android home screen:
public void setupShortCut(String iconName, String siteAddress)
{
Intent i = new Intent();
i.setAction(Intent.ACTION_VIEW);
i.setData(Uri.parse(siteAddress));
Intent installer = new Intent();
installer.putExtra(Intent.EXTRA_SHORTCUT_INTENT, i);
installer.putExtra(Intent.EXTRA_SHORTCUT_NAME, iconName);
installer.setAction("com.android.launcher.action.INSTALL_SHORTCUT");
sendBroadcast(installer);
}
The question is: how can I change current page of the home screen to create new shortcut not on the currently selected page, but on the specified one? Or maybe there's a way to specify home screen page number to put new shortcut on in addition to shortcut's name, bitmap etc.? | You cannot do this (as long as we talk about launchers in general). This would be of no real use as you do not know how many screens user got and if one of your choice is not full by any chance already. | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 2,
"tags": "android, icons, shortcut, homescreen, shortcut file"
} |
unexpected '' (T_ENCAPSED_AND_WHITESPACE)
error:
> Parse error: syntax error, unexpected '' (T_ENCAPSED_AND_WHITESPACE), expecting identifier (T_STRING) or variable (T_VARIABLE) or number (T_NUM_STRING) in C:\wamp\www\html\updatedtimeline.html on line 109
Im getting this error in my code and i would like to understand why? Thanks for any help
i want to add the email of the user logged in my html element
<h6 id="myemail"> </h6>
line 109:
echo "<script> document.getelementById('myemail').value= $_SESSION['email'] </script>"; | Try following:
<?php session_start();?>
<h6 id="myemail"> </h6>
<?php
echo "<script> document.getElementById('myemail').innerHTML = '{$_SESSION['email']}'; </script>";
?>
Please make sure that your `echo` should be placed after `<h6 id="myemail"> </h6>` is printed out.
**Please pay attention to the order of the code. You should make sure`<h6 id="myemail"> </h6>` is printed already before you `echo` script code.** | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": -4,
"tags": "javascript, php, html, syntax error"
} |
How to create socket in Linux?
I am looking for a way to create socket file in Linux. I want when I `cat` a file to see everything sent to certain port. Is it possible to use something like mksock to achieve this? | Server side :
nc -l -p 6666
Client side :
nc 127.0.0.1 6666 < /etc/passwd
that will print the `/etc/passwd` file on server's output.
Does this fits your needs ?
**Edit** :
it seems like you need to forge packets, so I recommend you using scapy | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": -2,
"tags": "linux, networking"
} |
Right view of binary tree without using queue in Java
HERE is the c++ implementation for right view of binary tree without using queue. When I try to convert it to Java, it is not working. Here is my Java code:
(I think most likely it is because I have not understood the algorithm properly and handling of maxLevel pointers/reference)
public static void rightView(TreeNode tNode){
int maxLevel = 0;
rViewUtil(tNode, 1,maxLevel);
}
public static void rViewUtil(TreeNode tNode, int level, int maxLevel){
if(tNode==null)
return;
if(maxLevel < level){
System.out.print(tNode.value + " ");
maxLevel = level;
}
rViewUtil(tNode.right, level+1, maxLevel);
rViewUtil(tNode.left, level+1, maxLevel);
} | In the spirit of @lifus' answer, but avoiding mutable state, you can use the function return to set `maxLevel`
public static void rightView(TreeNode tNode){
int maxLevel = 0;
rViewUtil(tNode, 1,maxLevel);
}
public static int rViewUtil(TreeNode tNode, int level, int maxLevel){
if(tNode==null)
return;
if(maxLevel < level){
System.out.print(tNode.value + " ");
maxLevel = level;
}
maxLevel = rViewUtil(tNode.right, level+1, maxLevel);
maxLevel = rViewUtil(tNode.left, level+1, maxLevel);
return maxLevel
} | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 3,
"tags": "java, algorithm, binary tree"
} |
Get info from another application
Basically what i want to do is see the value of a progress bar in an application from another application, If its possible.
I have been able to find the progress bar from my app with and get the WINDOWINFO:
[DllImport("user32.dll")]
private static extern bool GetWindowInfo(IntPtr hwnd, ref WINDOWINFO pwi);
But I'm not sure how or if its possible to get the value.
WINDOWINFO is explained here and here.
Any help or other ideas would be appreciated. | `GetWindowInfo` isn't going to tell you anything specific to a progress bar - only the standard window flags. Take a look at the documentation for Progress Bar Messages for how to interact with a progress bar.
You need to use the PBM_GETPOS message to get the current position of a progress bar as below:
const uint PBM_GETPOS = 0x0408;
[DllImport("user32.dll")]
private static extern IntPtr GetWindowInfo(IntPtr hwnd, uint msg, IntPtr wParam, IntPtr lParam);
uint pos = (uint)SendMessage(hwnd, PBM_GETPOS, IntPtr.Zero, IntPtr.Zero); | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 1,
"tags": "c#, window, pinvoke"
} |
Здрасьте, есть такая вот запись, что значит строчка Main main = new Main();
public class Main {
void useCar(Car car) {
car.driving();
System.out.println(car.getNumOfSeets());
}
public static voidmain(String[] args) {
Main main = new Main();
Car car = new Toyota();
main.useCar(car);
}
} | Здесь ты создаёшь экземпляр класса Main с помощью пустого(дефолтного) конструтора(Main()).
У тебя есть класс `Main` в нём есть 2 метода `useCar` и `main`. Метод `main`(благодаря этому методу `java` понимает откуда начинать ему работу) запускается самой `java` и в `main` ты создаёшь класс типа `Main`(Если у класса нет явной реализации конструктора, то он создаётся пустой конструктор самой `java` ) и `Car`. | stackexchange-ru_stackoverflow | {
"answer_score": 2,
"question_score": -1,
"tags": "java"
} |
Why must an abstract method be protected in a derived class?
When inheriting from an abstract class, why can't the protected abstract methods in an abstract base class be private when they are overridden in an abstract derived class?
Rephrasing, is it possible for an abstract method to be defined by a child abstract class, but then not accessible by a grandchild class?
Consider the simplified example:
public abstract class A
{
// This method is protected - makes sense
protected abstract void M();
}
public abstract class B : A
{
// Why can't this be private?
// Compiler forces it to be protected
// but this means grandchildren classes always have access to this method
protected override void M()
{
// Do something
}
}
public class C : B
{
// Is it possible for M() to be inaccessible here?
} | I don't believe this is possible due to how inheritance works. All children (derived classes) have everything a parent has, plus whatever extra stuff you need.
That said - if you want a child class to NOT have one of the methods its parent has, you can do it with interfaces. Simply define an interface which lacks the one method you want to restrict, and have both parent and child implement it. | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 2,
"tags": "c#, inheritance, abstract"
} |
What is the other way around of ToBsonDocument?
Say I have a business. If I want to turn an object whose class is Business into a BsonDocument, I would do
aBusiness.ToBsonDocument
Great.
What about if I want to turn a BsonDocument into aBusiness class? Is there an easy way?
**Public Shared Function ToBsonDocument(Of TNominalType)(ByVal obj As TNominalType) As MongoDB.Bson.BsonDocument Member of MongoDB.Bson.BsonExtensionMethods** | What you need to do is deserialize your BSonDocument into your class.
Without having a more complete view of your class I can't give a full example, but in general you would need to do something like:
Dim testBusiness As aBusiness = BsonSerializer.Deserialize(Of aBusiness)
You can find the API documentation for the BSonSerializer here
You can also see a similar question for C# here | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 0,
"tags": "vb.net, mongodb, bson"
} |
Astyanax Cassandra Double type precision
I'm trying to get a Double value from a Cassandra table with a double type column. I've created the table in CQL3 syntax:
CREATE TABLE data_double (
datetime timestamp,
value double,
primary key (datetime)
);
I've inserted a row:
INSERT INTO data_double (datetime, value) VALUES ('111111111', 123.456);
When I do:
SELECT * from data_double;
I get that the value is **123.46**
Why is the value rounded?
Thanks | The `cqlsh` utility by default will only display 5 digits of precision for floating point numbers.
You can increase this by creating a cqlshrc file with contents like the following:
[ui]
float_precision = 10
The cqlsh docs page provides more details on the available options.
**Update:** The location of the cqlshrc file changed at some point in Cassandra. The new default location is `~/.cassandra/cqlshrc`. You can also use a file in a different location with the `--cqlshrc` command-line option. | stackexchange-stackoverflow | {
"answer_score": 11,
"question_score": 6,
"tags": "cql3, astyanax, cassandra 2.0, cqlsh"
} |
jsonpCallback not calling function
Here's my jquery snippet that I can't get to work. I'm trying to call blackBackground() through jsonpCallback
$(document).ready(function()
{
function blackBackground(data, status)
{
console.log("black background");
//I want to eventually change the body style to black
}
$.ajax({
url: '
dataType: 'jsonp',
jsonp: false,
jsonpCallback: 'blackBackground'
});
});
Update:
jsonpCallback: 'blackBackground'
to
jsonpCallback: blackBackground
along with moving blackBackground to global scope. Thanks for all the responses. | The problem here is that the function `blackBackground` is not available in the global scope.
You can either expose the function in the global scope by declaring it like this:
window.blackFunction = function(){ .. }
...or use an anonymous function in the ajax configuration:
jsonpCallback: function(result){ .. }
I'd recommend the latter, as it will keep you global scope tidy a wee bit longer :) | stackexchange-stackoverflow | {
"answer_score": 4,
"question_score": 1,
"tags": "jquery, ajax, jsonp"
} |
Should one say "for forever" or "forever"?
I've always wondered about this.
When describing an exaggerated amount of time should one say "for forever" or "forever"?
As in:
> I have been waiting for forever.
or
> I have been waiting forever.
The argument being that the word "forever" is in itself a period of time, or it isn't. | "Forever" in this context is an adverb. You could also say that it's basically "for ever" without the space. As such, if you're saying that you have been waiting for a very long time, then the latter usage is right.
In the former usage, "forever" is used as a noun. It does not describe _how long_ you have been waiting; instead, as a noun, it represents _what_ you're waiting for. In other words, it means you're waiting for _forever_ , as in the period of time itself, which may itself either refer to an indeterminate point in time in the future or an indefinitely long duration of time. | stackexchange-english | {
"answer_score": 9,
"question_score": 7,
"tags": "word choice, prepositions"
} |
Not let the user unfocus the frame?
So you know how In Microsoft Word, when you go to File --> Options and it won't let you do anything else until you close it? Is there anything like that in Java? | Yes, they are called modal dialogs. Modality tutorial. | stackexchange-stackoverflow | {
"answer_score": 8,
"question_score": 1,
"tags": "java, swing, focus, frame"
} |
lambda calculus for functional programming
in lambda calculus (λ x. λ y. λ s. λ z. x s (y s z)) is used for addition of two Church numerals how can we explain this, is there any good resource the lambda calculus for functional programming ? your help is much appreciated | Actually λ f1. λ f2. λ s. λ z. (f1 s (f2 s z)) computes addition because it is in effect substituting (f2 s z), the number represented by f2, to the "zero" inside (f1 s z).
Example: Let's take two for f2, `s s z` in expanded form. f1 is one: `s z`. Replace that last `z` by f2 and you get `s s s z`, the expanded form for three.
This would be easier with a blackboard and hand-waving, sorry. | stackexchange-stackoverflow | {
"answer_score": 8,
"question_score": 4,
"tags": "functional programming, lambda, lambda calculus"
} |
preg_match this or this but not match any of this
so, I look around a while but I'm having problems.
I need a preg_match function with a regular expression that found words in a string, just to match the whole pattern, no replace or found position.
`"mct" or "MT" /i` (no case sensitive)
but at the same time, this string must not have any word starting or containing "md", "med", "burn", "mull", "des a", "hot tem" /i (also no case sensitive)
no case sensitive at all...
so I tried someting like this:
/(mt|mct)(?!med)(?!md)(?!burn)(?!mull)(?!des a)(?!hot tem)))*$/i
but it seems not working the way I expected.
Example of expected behavior:
$string |STATUS
McTNug10GdPap | TRUE
McTQQMdDobPap | FALSE (has "Md")
McT Pollo Esp Dobl Gd P | TRUE
MTD McPollo Spicy Med | FALSE (has "Med")
MegaBig Chikn Nugg | FALSE | You can use the following regex based off the requirements.
/^(?!.*(?:me?d|burn|mull|des a|hot tem)).*mc?t.*$/i
**Live Demo** | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 0,
"tags": "php, regex, expression, preg match"
} |
Missing 1 digit in time column read excel in pandas
I have excel that have format like this
| No | Date | Time | Name | ID | Serial | Total |
| 1 |2021-03-01| 11.45 | AB | 124535 | 5215635 | 50 |
Im trying to convert excel to pandas dataframe using below code
pd.read_excel(r'path', header=0)
pandas read the excel successfully however, I found strange result when I see the column time. the dataframe have below result
| No | Date | Time | Name | ID | Serial | Total |
| 1.0 |2021-03-01| 11.4 | AB | 124535 | 5215635.0 | 50.0 |
Column Time is missing 1 digit. is my method to read excel is not correct? | `read_excel` is interpreting your dot-separated time as a float, which is quite expected.
I suggest telling read_excel to see this column as a string and convert it to datetime afterwards:
df = pd.read_excel(r'path', header=0, converters={'Time': str})
df['Time'] = pd.to_datetime(df.Time, format="%H.%M") | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 0,
"tags": "pandas, dataframe"
} |
Create list of random numbers between x and y using formula in Google Sheets
I'm trying to create a list of 50 random numbers let's say between 100 and 500 with one formula in Gsheets. Is there any formula like 'apply this to x cells'?
What I tried so far is (and doesn't work). I hoped `randarray` function will 'force' `randbetween` function to create 2D array (`randarray` creates a list of numbers between 0 and 1).
={
RANDARRAY(50,1), ARRAY_CONSTRAIN(RANDBETWEEN(100,500),50,1)
}
> Error Function ARRAY_ROW parameter 2 has mismatched row size. Expected: 50. Actual: 1.
So this error indicates that `array_constrain` didn't help either. | try like this:
=ARRAYFORMULA(RANDBETWEEN(ROW(A100:A149), 500))
![0]( | stackexchange-stackoverflow | {
"answer_score": 4,
"question_score": 1,
"tags": "arrays, google sheets, random, google sheets formula, array formulas"
} |
Ruby - require 'watir-webdriver' - generates a LoadError no such file... Why?
I am new to Ruby and would really appreciate some help understanding what is going on here.
Summary:
Gem install watir-webdriver
Installs fine
start irb
require "watir-webdriver"
... LoadError: no such file to load --watir-webdriver
Surely this should respond
=> true
Why is it not finding the gem? Or what am I doing wrong?
!Console
I'm on win7, Railsinstaller (Ruby 1.8.7). | In 1.8.7 you need to require rubygems first.
require 'rubygems'
Some explanation here: How does require rubygems help find rubygem files? | stackexchange-stackoverflow | {
"answer_score": 13,
"question_score": 7,
"tags": "ruby, webdriver, watir, watir webdriver"
} |
Is it possible to bind the window texture to a texture unit?
The texture that gets rendered to the window is bound to Framebuffer 0. Is it possible to bind this texture to a texture unit, for use as a uniform sampler2D in a drawcall? | No. The default framebuffer (which is what is provided by the window system) has no corresponding texture object that you could sample from.
If you want to sample from any render output, you are going to need to create a custom framebuffer object and render to some texture object attachments that you can then sample from.
Another option is to blit the default framebuffer color buffer into another framebuffer color attachment. See: < | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 0,
"tags": "c, opengl"
} |
TIS-B anonymous address
I could not understand what is the difference between ADS-R with anonymous address (CF=6, IMF=1) and TIS-B CF=5, which on ICAO Doc 9871 is described,
for Version 1 as:
> Fine TIS-B Message AA field contains a non-ICAO 24-bit address
and for Version 2 as:
> TIS-B messages that relay ADS-B Messages using anonymous 24-bit addresses
Any specific example when CF=5 is used?
Thanks! | My question was due to the confusing mention of ADS-B in what was supposed to be either TIS-B or ADS-R.
I've now confirmed that the text on ICAO Doc 9871 Version 2 I quoted was due to a error.
In fact DO-260B, and even Doc 9871 Version 2 at table C-37 specify that TIS-B CF=4 is "Fine TIS-B message, AA field contains a 24-bit anonymous aircraft address".
ICAO e-mailed me confirming that this has been fixed into their working document. | stackexchange-aviation | {
"answer_score": 3,
"question_score": 7,
"tags": "ads b, tis b"
} |
What is algorithm behind the recommendation sites like last.fm, grooveshark, pandora?
I am thinking of starting a project which is based on recommandation system. I need to improve myself at this area which looks like a hot topic on the web side. Also wondering what is the algorithm lastfm, grooveshark, pandora using for their recommendation system. If you know any book, site or any resource for this kind of algorithms please inform. | Have a look at Collaborative filtering or Recommender systems.
One simple algorithm is Slope One. | stackexchange-stackoverflow | {
"answer_score": 30,
"question_score": 42,
"tags": "algorithm, collaborative filtering"
} |
Automatically resize window with JQuery
To extend the responsiveness to my site, I've added the below JQuery to handle situations when the screen width is below 1300px. It almost works perfectly, however - it doesn't take into account the screen size updating, I.e. when screen is less than 1300 it does apply the appends, however if I then adjust the screen to above 1300px it will keep the conditional changes.
$(window).on('resize',function() {
if ($(this).width() < 1300) {
$("#id").appendTo("#div");
$("#id").appendTo("#div");
}
}); | media queries would be the better solution, but if you wanted to keep what you already have use the following jquery to remove the item once it reaches full size again.
var isAppended = false; // place this at the top of your file
$(window).on('resize',function(){
var width = $(this).width();
// dont append unless it doesnt exist
// and size smaller than break size
if (!isAppended && width < 1300) {
$("#id").appendTo("#div");
$("#id2").appendTo("#div");
isAppended = true;
}
else if (isAppended && width >= 1300) {
$("#id").remove();
$("#id2").remove();
isAppended = false;
});
in order to use a media query to solve the problem
HTML
<div id="id1"></div>
CSS
#id1 {
display: none;
}
@media (max-width: 1300px) {
#id1 {
display: block;
}
} | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 0,
"tags": "jquery, css"
} |
Adding JS and CSS webresource to use in velocity template doesn't work in JIRA 6.4
Our JIRA project tab panel plugin was working fine with with external web resources (JS & CSS) until 6.3.9, after migrating to 6.4 they're no longer included in the velocity templates. How can we solve this problem? Has there been a change in the way web resources are included in velocity templates? Please help.
<web-resource key="project-tab-resources" name="project-tab Web Resources">
<resource type="download" name="project-tab.css" location="/css/project-tab.css"/>
<resource type="download" name="project-tab.js" location="/js/project-tab.js"/>
project-tab | I have found the solution:
We are running a local instance of Jira via `atlas-debug` to be able to reload frontend changes without recompiling. The right way to do the upgrade is:
* change the `jira-version` in `pom.xml`.
* **Before** running `atlas-debug` run `mvn clean`
* run `atlas-debug` as usual
Be careful with `mvn clean` because if you are using an _in memory_ database it will be destroyed | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 1,
"tags": "jira plugin"
} |
Safely rendering a user's template/view?
I have a model which has a template field. This template is HTML and has variables which get substituted. This template is then converted into a PDF using wicked_pdf.
How should I take the template which the user enters and safely do variable substitution? Allowing it to be an ERB template seems to be setting myself up for some huge security holes. What safe solutions are there?
Edit:
So, for example, I have my template class/model which has two fields, a name and an HTML field. This is a user editable class. There will be specific variables available to the HTML in the template class (Company Name, price, etc.). I am hoping to use a HTML templating system, but since this is user created content, it isn't trusted. Only variable substitution will be done, nothing more. | Rails provides a couple of helper functions, namely `h`to escape values on display for preventing such behavior. <%= h @user.name %>
`h` is an alias of `html_escape` | stackexchange-stackoverflow | {
"answer_score": 0,
"question_score": 2,
"tags": "ruby on rails"
} |
Prolog list manipulation
I have a question and need someone to correct me:
`store(wyoming, [evan, sandra], [storybook, fiction, general]).`
`store(brooklyn, [haas, maria], [fiction, schoolbook, religion]).`
`store(oakland, [rich, walker, dina, vince], [storybook, schoolbook, fiction]).`
if i consult `?-locations(storybook).` the answer must return true because storybook available at more than one store. i write my predicate like this:
locations(Book) :- store(_, [_], [Books]), member(Book, Books).
when i consult, i will return false no matter what type of book i enter. how to solve this? | After applying mbratch suggestion, you still need to check when a `Book` is available at more than one store. The easy way, inefficient because if 'analyzes' all the DB:
locations(Book) :-
findall(Book, (store(_,_,Books), memberchk(Book, Books)), L),
length(L, N), N > 1.
We can make it less verbose:
locations(Book) :-
findall(_, (store(_,_,Books), memberchk(Book, Books)), [_,_|_]).
Note I used memberchk/2 instead of member/2. It's faster and, as a side effect, avoids answering true in the case where there is only a store matching, but with the book present more than once.
To avoid scanning the entire database, a join will do:
locations(Book) :-
store(X,_,BooksX), memberchk(Book,BooksX),
store(Y,_,BooksY), Y \= X, memberchk(Book,BooksY),
!.
The final cut prevents multiple useless answers for the same `Book`. | stackexchange-stackoverflow | {
"answer_score": 0,
"question_score": 1,
"tags": "list, prolog"
} |
Some question about classes in plugin
I am using Ruby on Rails 3 and and I am trying to implement a new plugin. In order to learn, I am viewing inside and I am studying some popular plugins.
What I choosed is WillPaginate and in a its file there is something like this:
module WillPaginate
class << self
...
end
end
if defined? Rails
WillPaginate.enable_activerecord if defined? ActiveRecord
WillPaginate.enable_actionpack if defined? ActionController
end
I would like to know
1. **Why the`if defined? Rails` statement is outside the `module` statement? When will be run istructions inside that?**
2. **What means and how can\should I use`class << self`?** | 1. `module WillPaginate` defines Ruby name scope and groups these methods so they can be later included with one call into some class. The `if defined? Rails` is outside the module because the code inside that `if` might include the **whole** module into some ActiveRecord class. And the `if` is executed exactly at the time when `will_paginate.rb` file is loaded.
2. All methods in that block are class methods. So later it is possible to make calls like `YourModelClass.foo`. | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 1,
"tags": "ruby on rails, ruby, ruby on rails 3, class, plugins"
} |
CSS - Add border to all divs
I was wondering if there was any "easy" way to add through css lets say:
`border: 1px solid red;`
to all divs no matter what their id´s are.
I realize this might be a very very basic question (or no possible at all) and I hope it is clear enough.
Just to clarify, lets say I´ve got:
HTML
<div id="one">
</div>
<div id="two">
</div>
and CSS
#one{
height: 10px;
width: 10px;
}
#two{
height: 10px;
width: 10px;
}
The result I actually want is:
#one{
height: 10px;
width: 10px;
border: 1px solid red;
}
#two{
height: 10px;
width: 10px;
border: 1px solid red;
}
I want to achieve this without having to go one by one.
Thanks in advance!!
Please ask for any clarification needed! | div {
border: 1px solid #000000;
} | stackexchange-stackoverflow | {
"answer_score": 34,
"question_score": 15,
"tags": "css, html"
} |
Spam is Killing Me - Can I use GMail as a spam filter?
I'm getting at least 50 Viagra ads a day and it's driving me insane.
I currently have a hosted MS Exchange account and a Gmail account. My Gmail account forwards to my Exchange account. Both of my addresses are used evenly, and it has been really nice to have all of my e-mail end up in my Exchange box. I like replying from one address consistently, which is my Exchange address.
Spam sent to my Gmail address is always caught, where spam sent to my Exchange is getting passed straight through to me. I don't want to have two spam filtration systems that have quarantines that I need to check frequently for false positives.
Here is my question:
Can I setup my MX records such that all e-mail sent to my Exchange address is forwarded to my Gmail account, which will then forward it to my Exchange account? Kind of like using Gmail as the middle man. | Look into the Postini services from Google. | stackexchange-superuser | {
"answer_score": 7,
"question_score": 5,
"tags": "email, spam prevention"
} |
Add js and css files to views in zend framework
I want to add script files and css files to my php view page inside a module, I try to make like this
<base href="<?php echo $this->baseUrl(); ?>" />
<link rel="stylesheet" type="text/css" href="<?php echo $this->baseUrl('style/ui-lightness/jquery-ui-1.8.18.custom.css'); ?>"/>
and like this
<?php
$this->headScript()->appendFile('js/jquery-1.7.1.min.js');
echo $this->headScript();
?>
but both of them do not inlucde the files. I put my css and js files inside the helpers folder of view folder. | Your JS and CSS files are in the wrong place.
The helpers folder of the the view folder isn't even in the web root (by default), so you literally cannot request it from the web server.
Put them somewhere under the web root, and then give a path to them in the view script.
As your view script may be a few folders deep, I tend to use absolute paths. (/js/jquery...).
You could alternatively programmatically calculate the absolute or relative path to the file and use it. (If you're at controller1/ you'll need to do ../js/jquery, but if you're at controller1/action/ you'll need to do ../../js/jquery.) | stackexchange-stackoverflow | {
"answer_score": 2,
"question_score": 0,
"tags": "javascript, css, zend framework, include"
} |
Div height issues , Div height does not cover whole body
I have slider panel ,what i am doing , when my slider open then it's cover all height, but not able to this , when i am going with body overlay hidden then ,height is fixed and full content is not showing,<
body{
background-color:#FFF;
height:100%;
width:100%;
margin:0;
color:#ccc;
font-size:3em;
line-height:100px;
text-align:center;
overflow:hidden;
}
.slidernav{
background:#000;
position:absolute;
width: 100%;
height:100%;
top: 0;
right:-100%;
z-index:9999999999999999999999;
overflow:hidden;
}
html
<html>
<body>
<div class="slidernav"><div>
</html>
</body> | Instead of `overflow:hidden;` use `overflow-x:hidden;` | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 0,
"tags": "html, css"
} |
Add-remove class to Fixed element
Trying to add and remove class to a jQuery sticky Fixed element `h2.sly-scroll-title3` _(Title 1)_ when `#Label1` on the viewport. Means add class `.extraclass` to `h2.sly-scroll-title3` only when `#Label1` block on the viewport and remove class when its not on viewport.
HTML:
<div id="Label1">
<div class="bottom-label-post1">
<h2 class="sly-scroll-title3" >Title 1</h2> <!-- Scroll Element -->
<div class="clear"></div>
<div class="list-label-widget-content">
Content 1
</div>
</div>
</div> <!-- End -->
Please see this fiddle: <
Thanks in Advance. | Try `sticky-end` event. The code will be like below -
$('h2.sly-scroll-title3').on('sticky-start', function() { $('h2.sly-scroll-title3').removeClass('extraclass'); });
$('h2.sly-scroll-title3').on('sticky-end', function() { $('h2.sly-scroll-title3').addClass('extraclass'); });
There are other events given below as per documentation-
$('#sticker').on('sticky-start', function() { console.log("Started"); });
$('#sticker').on('sticky-end', function() { console.log("Ended"); });
$('#sticker').on('sticky-update', function() { console.log("Update"); });
$('#sticker').on('sticky-bottom-reached', function() { console.log("Bottom reached"); });
$('#sticker').on('sticky-bottom-unreached', function() { console.log("Bottom unreached"); }); | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 0,
"tags": "jquery, html, addclass, sticky, removeclass"
} |
Rails 3.1 pass data through a post
In my application, I've a ' **warehouse** ' model that own several fields such as id,name,description, etc, and a boolean field called 'done'.
In my view, I want to insert a button or link field,which, when clicked, should set (through HTTP POST method) warehouse.done = true How can I do this?
Notes: User cannot input warehouse.done field so I suppose to pass it to application as hidden field | I made a couple of assumptions on the views, controller.
html
<a href="#" id="set-warehouse-done"> DONE </a>
<input id="warehouse-id" type="hidden" value="24">
js
$(document).ready(function() {
$('#set-warehouse-done').click(function() {
$.ajax({
url: '/warehouse/' + $('#warehouse-id').attr('value');
type: 'POST'
data: done: true
});
});
}
warehouse_controller.rb
def update
@warehouse = Warehouse.find(params[:id])
if params[:done]
if @warehouse.update_attributes(:done, params[:done])
flash[:notice] = 'Warehouse updated successfully'
else
flash[:error] = 'Could not update warehouse' | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 1,
"tags": "ruby on rails"
} |
can an iPhone application create more than one button on the applications screen?
I'd rather write an application with two buttons on the applications menu than use just one - and have two paths through the app.
Can this be done?
Is there some way of creating buttons on the applications screen?
Thanks. | No. The iPhone's home screen doesn't have "buttons"—it has app icons. Each icon represents an app; when the icon is tapped, the app is opened. If you wanted multiple icons, you would need multiple apps. You could potentially create another app that, when launched, closed itself and opened your main app using a URL (see here).
Why do you want to have multiple icons that open the same app? It sounds quite illogical to me... | stackexchange-stackoverflow | {
"answer_score": 4,
"question_score": 0,
"tags": "iphone"
} |
Is it possible to extend the Service Fabric Explorer with custom UI?
I don't see any documented plugin framework for extending the functionality of the Service Fabric Explorer. Is there perhaps an undocumented one (or some samples), which I can use to add custom actions / information to my services? | SFX does not contain a feature like this, but the source is available online on github though, you could either:
* Request as a feature and wait to be accepted and implemented by someone
* Fork the code and implement yourself, and maybe submit back to upstream repository. | stackexchange-stackoverflow | {
"answer_score": 0,
"question_score": 1,
"tags": "azure service fabric"
} |
Add two fields in auto suggestion in solr
I have two field in Solr from which I want to generate auto suggest,
and also I want to show result distinguishly for name and college. For eg. if I search for "nan" the auto suggest sholud give result with both fields like for name it is nandy and college nandas institute. How is this possible? | By using copyField you can copy name and college field to the copyField and use this field as a suggester. | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 0,
"tags": "search, solr, autocomplete, lucene"
} |
Saving PDF to Local Disk C#
I am trying to save a PDF to the document folder. I have googled and came across a lot of resources but none of them worked for me. I have tried using showfiledialog which did not work. What I want is to save my PDF file to the documents folder. I need this done for a school project and this is the only part that has stumped me. So far this is my code:
private void savePDF_Click(object sender, EventArgs e)
{
FileStream fileStream = new FileStream(nameTxtB.Text + "Repair.pdf", FileMode.Create, FileAccess.Write, FileShare.None);
Document document = new Document();
PdfWriter pdfWriter = PdfWriter.GetInstance(document, fileStream);
pdfWriter.Open();
PdfContentByte cb = pdfWriter.DirectContent;
ColumnText ct = new ColumnText(cb);
document.Open();
... | You should add your content (nameTxtB.Text) to Paragraph not to FileStream
using System.IO;
using iTextSharp.text.pdf;
using iTextSharp.text;
static void Main(string[] args) {
// open the writer
string fileName = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), "Repair.pdf");
FileStream fs = new FileStream(fileName, FileMode.Create, FileAccess.Write);
Document doc = new Document();
//Create a New instance of PDFWriter Class for Output File
PdfWriter.GetInstance(doc, fs);
//Open the Document
doc.Open();
//Add the content of Text File to PDF File
doc.Add(new Paragraph("Document Content"));
//Close the Document
doc.Close();
System.Diagnostics.Process.Start(fileName);
} | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": -1,
"tags": "c#, winforms, itext"
} |
MySQL Query for selecting values based on 2 columns
I have a table with 4 columns: id, A, B, C. I need to select A based on B and C.
B is a filter and has integer values, C are the filter options, also integer.
I tried this:
SELECT a FROM table WHERE (b=1 AND c IN (5,6,7)) AND (b=2 AND c IN (9,10,11))
But that doesn't work because B can't be 1 and 2 at the same time. I tried with OR:
SELECT a FROM table WHERE (b=1 AND c IN (5,6,7)) OR (b=2 AND c IN (9,10,11))
This returns A but wrong... I need both conditions to be correct.
How can I make this query work?
Thank you! | Group by `a` and then you can check the conditions in the `having` clause
SELECT a
FROM your_table
GROUP BY a
HAVING sum(b=1 AND c IN (5,6,7)) > 0
AND sum(b=2 AND c IN (9,10,11)) > 0 | stackexchange-stackoverflow | {
"answer_score": 1,
"question_score": 1,
"tags": "mysql"
} |
Is there a way to read DjVu files on a 4th gen Kindle?
DJVU format is a very good format both in terms of file size an readability.
Is there a way that I can read DjVu files on a 4th generation Kindle? | There is no out of the box possibility.
The easiest way would be to convert the file to pdf, of course this would make the DjVu advantages disappear.
The alternative is to modify your Kindle by installing a compatible reader. One possibility that is still actively developed is Librerator (which is also a superior for viewing larger pdfs). You will however have to jailbreak your Kindle and install KUAL, which will possibly void warranty. | stackexchange-ebooks | {
"answer_score": 10,
"question_score": 18,
"tags": "kindle, djvu, 4th generation kindle"
} |
ASUS S400CA BIOS Upgrade-RAM doesn't work anymore
I have an Asus S400CA laptop and today, I upgraded the BIOS firmware from version 203 to 209 using the Asus Windows flash utility. Flashing was successful and even the verification was OK. So, I restarted the system and ... just a black screen shows up. It doesn't even boot to BIOS anymore.
The S400 model has 4G RAM soldered on the motherboard and I have an extra 4G ram installed (so 8G in total). It was working fine before the BIOS upgrade but now when I removed the installed ram, it works fine, when I put it back, it stops working.
So, the problem is somehow about the mixture of the 209 version of BIOS and the extra RAM. In the description of the 209 it is written "support onboard memory". To me, it means they wanted to fix something but they ruined it.
I just wonder if anybody has a solution for it? One solution might be to downgrade the BIOS to an older version but I couldn't make it. | Ok, I fixed the issue by downgrading the BIOS back to version 203. Niether the WinFlash utility nor the EasyFlash can be used to downgrade the BIOS on new Asus laptops. I also used the DOS based AFUDOS utility and it also failed to downgrade the BIOS.
However the trick is very simple: run the WinFlash utility with `/nodate` switch from the command line. For more details see here. | stackexchange-superuser | {
"answer_score": 2,
"question_score": 1,
"tags": "laptop, memory, bios, upgrade, asus laptop"
} |
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