What is the strategy to beat Dragonite?

Question: Is there a pokemon that one can level up (or some other strategy) that would counter Dragonite well?
Comment: Whenever you need to beat Dragonite, just remember what this famous rapper said, "Ice Ice Baby".
Comment: There's... strategy?  You press the screen until it dies!
Answer: Dragonite is nothing special. Ok, it has high stats and a few resistances but the same tactics work on it. Dodge its attacks and try to get type advantages.
If you haven't read it already, this question has answers about how to dodge optimally. It applies to all pokemon, but is especially important against higher CP opponents, which Dragonites usually are.
Dragonite is a Dragon/Flying pokemon. This gives it a double weakness to Ice, making Ice moves extremely effective. It is also weak against Dragon, Rock, and Fairy moves. A pokemon with one or both moves of this type can deal a lot of damage.
Bear in mind, however, that Dragonite's resistances include Water, Fighting, and Ground, which Ice and Rock pokemon often use. It's also resistant to Fire, Bug, and Grass. Make sure neither of your attacks are these types.
Dragonite has a few attacks- fighting the Dragonite once to discover them will make fighting it a second time much easier. Its basic moves are Dragon Breath and Steel Wing, with Dragon Breath being significantly more popular due to its STAB bonus.
Steel and Fairy pokemon are resistant to Dragon moves. Dragons are weak against them but unless you are using your own Dragonite, that's not an issue.
Steel Wing Dragonites are less popular but are extremely dangerous. Steel is super effective against Fairy, Ice, and Rock pokemon- all of Dragonite's weaknesses. Steel is, fortunately, ineffective against Water so a Water/Ice or a Water pokemon with Ice moves can do well here.
Dragonite has 3 possible special attacks. Dragon Claw and Dragon Pulse are dragon- see above. Hyper Beam is normal type. It's also Hyper Beam. Don't worry about type advantages here- if it hits you, you'll probably die.
And so, the best options I've found:

A bigger Dragonite. Obviously.
Non-dragons with Dragon attacks. I have two Gyaradoses for this- they know Dragon Breath and Dragon Pulse and between them have destroyed CP 3000 Dragonites.
Water/Ice types with double Ice moves. Lapras is the strongest option here but Cloyster or Dewgong also work. They do need to both be ice moves (in Lapras' case, ice and dragon) because of Dragonite's resistance to Water.
Magneton. Neutral effectiveness, resistant to everything Dragonite can use.
Fairy types. Clefable and Wigglytuff are bad against Steel Wing, but resistant to Dragon and can have at least one super-effective STAB Fairy move.
Slowbro is also good because it has lots of health and can have Ice Beam which does 65 damage now
Answer: The strategy behind defeating Pokemons lies in the "Type" of Pokemons; by using a Pokemon with a super effective move. Dragonite is a dragon type Pokemon, which is weak against Dragon-type & Fairy-type moves (Fairy types come in later generation of Pokemon series).
So, 1 strategy is to use a Pokemon with Fairy-type moves against Dragonite to defeat it.
There are many Pokemons in Pokemon GO that may know Fairy type moves (refer to the wiki linked above) and you can use those moves to effectively defeat Dragonite easily.
An alternative solution is to look at the other type of Dragonite and which is - Flying.
Flying type Pokemons are weak against - Ice, Rock and Electric.
But here, Electric won't work well as Dragonite has high Electric moves resistivity.
So, the key to defeating Dragonite is to use a Pokemon with Rock or Ice type moves in Pokemon GO.
Here are the possible Rock and Ice type Pokemons you can use against Dragonite (if they have ice or rock type move):

Dewgong - An Ice type Pokemon which is sure to have either a Basic or a Special take of Ice type. I've again and again used Dewgong's Ice type super-effective moves to defeat Dragonite.
Slowbro - Again, Slowbro would sometimes have Ice type move like Ice beam which is a super effective move.
Golem - A Pokemon with rock type moves
Aerodactyl - Aerodactyl is Rock and Flying type Pokemon which may have those super-effective rock moves against Dragonite.

There are many other Pokemons like Diglett, Shellder, Kabutops, Lapras, etc which may have Ice or Rock type move which can be used to defeat Dragonite faster as these moves are super-effective to it.
Comment: Please add any relevant information to your answer instead of relying on a link—links can and do "break" when sites go down or are reorganised, which will make the link useless. Since the mission of Arqade is to store useful answers forever, summarising the relevant information from the link will both improve your answer and protect it from future breakage.
Comment: If Dragonite itself knows electric type moves ((which it doesn't in Pokemon Go)) That would make an electric pokemon **more** effective against it, not less, since it would be super effective vs Dragonite and resist one of its' moves. Additionally, Fairy type moves are super effective vs Dragon types and Fairy types resist Dragon Type moves,  making Fairy pokemon good for taking down Dragon Types.
Comment: @RFKomos Yes, Dragonite do knows Electric type moves in the actual GBA games. Don't know why it doesn't in Pokemon GO. And NO, Dragonite's that wouldn't make electric type moves super effective against dragonite (does any electric type Pokemons feel Opposite Electric moves as super effective? Electric is dragonite's 3rd type)

Fairy types were the one I didn't consider since they were introduced in the later generation but are still included in Pokemon GO. I've edited the answer to include it. Thanks for reminding that.
Comment: The answer is already explained in depth.
Comment: Aerodactyl only has one rock-type move and it is literally one of the worst. You are better off using almost anything else, even after weaknesses are considered.
Answer: I have had great luck with Clefable. Fairy type, for whatever reason, is super effective against Dragon types. Clefables are beefcakes, and they can put out a surprising amount of damage. Alternatively a decently powerful Jolteon will do just fine.
Remember, you only get a 20% bonus either way for typing. Focus on building a diverse, high CP team and you'll do fine.
Answer: The trouble with using Clefable against dragonite is that Clefable's normal moves are not fairy at all! They are "Pound" (normal) and "Zen Headbutt" (psychic).  Neither is specially effective against dragons. The best Clefable charge move against dragons is "Moonblast", but you don't use it often enough to defeat Dragonite.  Dragons with Steel Wing are super effective against Clefable.  Wigglytuff fares just as poorly with similar move disadvantages.  You have to forget about the so-called fairy advantage in Pokemon Go.
What I have succeeded with repeatedly is big Water pokemon: Vaporeon and Gyarados.  Sunday I trained at a friendly Gymn with great prestige and with the lower three Pokémon being 2250 Arcanine, 2250 Charizard, and 2400 Dragoniite.  One Vaporeon defeated Arcanine and Charizard then weakened Draginite enough so that the second Vaporeon defeated not just Dragonite but also the Snorlax above.  Vaporeon followed by Gyarados was equally effective, but Vaporeon followed by Clefable was never able to defeat the bottom three.  The Vaporeon have Water Gun/Hydropump, the Gyarados has Bite/Dragon Pulse, and Clefable Pound and Moonblast.  My best guess is that the Dragonite had Steel Wing/Dragon Pulse.
Answer: I use my 1400 dewgong to defeat many 2300+ dragonites. The frost breath is super effective against the dragonite and it can shoot a frost breath each second which makes it more lethal.
Answer: I find that my 1700 CP Steelix can take down a 3200 CP Dragonite as long as I dodge Hyper Beam! Steelix is a Steel-type so Hyper Beam is less effective against me. My primary move is Dragon Tail, which is super-effective against Dragon-types and I have a Steel-type charge attack. I bring out Steelix for every Dragon-type. That said, Cloyster and Dewgong with Ice-type moves also work.

What is the strategy to beat Dragonite?


Does Angry Birds and other games have Leaderboard on Android devices?

Question: I went to a Best Buy store and tried Android tablets but didn't see any Leaderboard for Angry Birds Space edition -- is it because it is not logged in as a game user or does Android have a standardized Leaderboard similar to iOS's GameCenter yet?
Answer: Android as a platform doesn't have any equivalent to GameCenter currently. Some Android games use OpenFeint for leaderboards and achievements, but it's not an official standard of any kind and it's not implemented in the Angry Birds games specifically. Other games choose to implement their own leaderboard systems (PewPew does this, for example).
Answer: There are a few other options out there such as Swarm (aka SwarmConnect) that have similar functionality (leaderboards, achievements, etc.) for Android games.  On Android it often comes down to developer preference.
Answer: Rovio now offers Rovio Account for their games on iOS and Android.
They describe it thus:

Rovio Account lets you store your game progress and continue playing on another device.

As of this writing, only The Croods and the original Angry Birds use Rovio Accounts, but I expect the other games in their stable to follow along fairly quickly.
This is not related to the just-announced Google Play Games, which is a general platform for Android.


Class design for instantly switching between free-roaming world to/from battle world?

Question: I plan to have an isometric world, which can be freely roam around. However, I desire the system to instantly apply the grid onto isometric world for battling system on any random encounter. Therefore, from what I expect, I should have a class of character that can generally switch between free-roaming and battle system. However, because I am still new to game programming, I do not know how should I approach this. If I make my character class such that I could abruptly derived it into either Free-roaming or Battle system, it may sound convenient, but I will have to implement this feature for all other class too (enemy, object, etc.). If I use Interface, then I won't have flexibility to add extra function to certain special class of object (maybe boss?). Or should I have a set of hierarchy of interface to tackle this problem? If so, it would be too complicated. Therefore, any suggestion?
Answer: Two "philosophical" points:

Whenever, after making a design decision, you say "I will have to implement this feature for all other class[es] too" it means you aren't modeling the desired behaviour in the most efficient way ("Carve nature at its joints." -- Plato). In general: Don't Repeat Yourself (DRY).
Don't confuse classes and objects in your code with classes of concepts and real-world objects. They are ways to organize code - to DRY - nothing more, nothing less. For a concrete example of this, see: How to avoid game objects accidentally deleting themselves in C++ (A game object's death is confused with calling delete on the object that represents it.)

I say "philosophical", because you will need to ignore the above and learn it yourself through experience, so here's my suggestion:
Use a state machine to switch your game object's behaviours
Your game has two states: free-roam and grid-battle. So make those two into sub-states of the "playing the game" state. See http://create.msdn.com/en-US/education/catalog/sample/game_state_management for an XNA-oriented approach. In free-roam you use a camera that's attached to the player character, in grid-battle you render a hex-grid and lock the camera in a fixed position for an overview of the battlefield.
For your game objects, you can reference the State design pattern, which is a more generic variant of the previous link. It enables you to change an object's behaviour depending on its state. Whenever your game's sub-state switches (from free-roam to grid-battle or vice versa), you will need to switch the relevant game objects states as well.
A possible class hierarchy is this:

GameObject { setGridBattle() setFreeRoam() }

class PlayerObject { move() { this.state.move(); } }
class BossObject { move() { this.state.move(); }   explode() { this.state.explode(); }

interface GameObjectState

interface PlayerObjectState { move(); }

class PlayerObjectGridBattle { move() { moveOverGrid(); }
class PlayerObjectFreeRoam { move() { moveFreeRoam(); }

interface BossObjectState { move(); }

class BossObjectGridBattle { move() { moveOverGrid(); } explode() { boom(); } }
class BossObjectFreeRoam { move() { moveFreeRoam(); } explode() { /* nothing happens */ } }

Expanding on this could have a MovingObject and a MovingObjectState, from which PlayerObject/EnemyObject and PlayerObjectState/EnemyObjectState inherit, maybe in that case EnemyObject gains a doAI() method, but the move() method from MovingObject (and MovingObjectState) is shared between PlayerObject and EnemyObject.
Comment: Thanks, I'll try experimenting around with your philosophy, first. I am still inexperience when it comes to designing architecture. This is not because I don't know how to design, but I can't decide on the best approach to solve the problem. It is rather a lot easier to accurately know my next objective and search for solution than to be uncertain of what my next objective is.
Comment: If in doubt just toss a coin and go for it, because that's the way you'll learn and in the end the game is the playing experience, not the technology behind it. Your players won't know or care if you applied design patterns or DRY. :-)


Can't remove gem

Question: Have a very strange problem. I have RVM and rails project. I used 'breadcrumbs_on_rails' gem and I had it in my Gemfile. After one update I got some errors in this gem, so I tried to roll back to previous version. I wrote version in Gemfile, ran bundle update - but nothing changed, there were still errors. I tried totally remove this gem from Gemfile, but... it's helpers were still working! I uninstalled gem completely, all versions, by running gem uninstall, cleared tmp folder of project, rebooted, but it is still working. What can be the reason?
Answer: Have you tried using
<code>bundle exec gem uninstall GEM_NAME
</code>
For RVM users:
you have to use this method if you've set up a gemset for your particular project.
Running gem uninstall GEM_NAME from the project folder will uninstall GEM_NAME from your global/system level gemset instead of bundler's.
Answer: Problem was in conflict of two gems
gem twitter-bootstrap-rails have exactly same methods - add_breadcrumb and render_breadcrumbs. And breadcrumbs were rendered by this gem, not by breadcrumbs_on_rails.
So, it turns out, that gem was removed successfully

Can't remove gem


What is Surya Sidhdhant? How Bhaskaracharya was the first to discover gravity, 500 years before Sir Isaac Newton?

Question: What is Surya Sidhdhant? How Bhaskaracharya was the first to discover gravity, 500 years before Sir Isaac Newton?
It is said that many years ago Bhaskaracharya discovered gravity using Surya Sidhdhant. What is that?
Comment: Bhaskaracharya was not the first to discover Gravity here. Vaishesika Sutras which are summarizing texts of Vaishesika School of Hinduism clearly discuss about gravity. See my answer here: http://hinduism.stackexchange.com/questions/9102/are-there-any-references-to-gravity-in-hindu-scriptures/14860#14860
Comment: What [Surya Siddhanta](https://en.wikipedia.org/wiki/Surya_Siddhanta) is.
Answer: Surya Siddhanta is the ancient Indian Astronomical treatises which has a significant importance in Vedic astronomy.
It was used for knowing the positions of planets in the sky, calculation of eclipses, solstices, sidereal motion, and many other complex mathematical & trigonometric calculations.
It was also the main backbone for Indian calendar calculations. The panchAngam was largely based on these siddhantas. However, now a days Drik system is more commonly used in the panchAngas.

In a work called the Pañca-siddhāntikā composed in the sixth century
  by Varāhamihira, five astronomical treatises are named and summarised:
  Paulīśa-siddhānta, Romaka-siddhānta, Vasiṣṭha-siddhānta,
  Sūrya-siddhānta, and Paitāmaha-siddhānta. Judging from the epoch dates
  in the work, Plofker suggests that this Sūrya-siddhānta was composed
  or revised in the early sixth century

Wiki
This book has 14 chapters. They arc:

Chapter 1 — Of the mean motion of planets, Preface, division of time,
  measurement of Yugas ( Yugamana), number of days, aharganas,
  revolutions, Mean of bhagana planets etc., conjunction and node of
  apsis for planets (Mandocca and sighra), Deshantara and inclination of
  their path to the ecliptic (parama vikshepa) .
Chapter 2 — Of the true places of the planets; Causes of planetary
  motion, types of motions, determination of sines (jya), declination
  and finding out the Kendra, determination of circumference from the
  base and perpendicular and their results of sine and cosine, corrected
  position of the planets, correction of bases, corrected motion, true
  latitude (vikshepa), length of day and night, Chara, Tithi,
  constellations (nakshrata), yoga, karana (portions and halves of lunar
  days).
Chapter 3 — Of direction place and time; Determining east-west
  meridian, part of solstice, equinoctial shadow, sine of co-latitude,
  zenith-distance, measure of amplitude, angle of the cone, Niraksha,
  point upon ecliptic (Lagna) and meridian ecliptic point (Dashama).
Chapter 4 — Of eclipses especially of lunar eclipse; corrected
  longitude of moon, measure of sun and the shadow (chdya), obscuration
  (Grasa), half-duration of the eclipse (Stithyardha), corrected
  perpendicular (Kotii), Valanarhsa (degrees of deflection).
Chapter 5 — Of parallax in solar eclipse; parallax in longitude of
  moon (Candra Lambana), parallax in latitude, solar eclipse
  (Suryagrahana).
Chapter 6 — Of the projection of eclipse; Parilekhadhikdra
Chapter 7 — Of planetary conjunctions; planetary conjunctions
  (Grahayutyadhikara), Akshadrikkarma, Ayanadrikkarma, disc of the
  planet (Grahavimba) viewing of the planets and encounter (Yudha)
Chapter 8 — Of the constellations; planet-constellation conjunction
  (Yutyadhikara), position of the constellations.
Chapter 9 — Of heliacal rising and setting; containing; rising and
  setting (Udaydstddhikdra), determination of time, portions of time
  (Kdldngsa).
Chapter 10 — Of moon's rising and setting and elevation of her cusps;
  sringonnati.
Chapter 11 — Of certain malignant aspects of sun and moon;
  Patadhikara, Vyatipdta, Determination of time, Gandaka, Bhasandhi.
Chapter 12 — Of cosmogony, geography, dimensions of the creation;
Spiritual science, Kakshasthiti, Pole, Bhadrasva, Yamakotl Lanka,
  Ketumala, Polar star, Distance from the earth.
Chapter 13 — Of armillary sphere and other instruments.
Chapter 14 — Of the different modes of reckoning time.

Source of contents


How to see what's using battery right now?

Question: Occasionally I've noticed a problem with my Lumia 950 where it gets rather hot and the battery discharges very quickly (10-15% per hour), even when the phone is not in use. This happens very infrequently, which makes debugging difficult. I've looked at the battery use report, but it only offers three time frames - 24 hours, 48 hours and 1 week. Even with the first option, the data is often heavily skewed by some resource-intensive app (e.g. a game) that is no longer running. Is there any way to see what's using battery power right now, as the problem is occurring?
Answer: There's a Task Manager app which is similar to the native PC version. It displays what background processes are running (in the background) and you can terminate them too.
P.S. There's an app called Battery X , it is good with tracking your battery's usage, strength, performance etc.
Comment: The mobile task manager UWP app is a much better choice though. https://www.microsoft.com/en-us/store/p/mobile-task-manager/9nblggh6hfv1#


What is the difference between 人民 and 民族?

Question: What is the difference between 人民 and 民族, for example in 中华人民 vs. 中华民族?
Comment: I think there is no word of "中华人民", you may want to say "中国人民" (the Chinese People). The formal official name of China is "the People's Republic of China", in Chinese "中华人民共和国", but that's another story, because here 中华 and 人民 are two words.
Answer: 人民 is translated as "(the) people". You can find it in popular expressions like:

人民共和国 = People's Republic; as Huang said in the comments, if we include China it becomes "中华人民共和国"
人民币 = Renminbi (the Chinese currency. 币 means "money, coins, currency".)
人民日报 = "People's Daily" (a newspaper)

民族 means "ethnic group, nationality", for example:

中央民族大学 Central University for Nationalities

All of the examples have been taken from the CEDICT dictionary.
Comment: I think the word "people" can mean "race" and in this case, it's countable noun and means "民族".
Comment: More than that. 人民 is in fact a political term. It's a subset of citizen, excludes the ones who's political right has been deprived, and the so called 敌对分子(hostile).
Answer: The first means "people" as in citizens or nationals and the second means "ethnic group".
Comment: Would you mind on expanding your answer?
Comment: Welcome to the site. Good answer, and an upvote to get you going.
Answer: 人民:People refer to a collection of people.
民族:With a common language, regional, economic life and its performance in the common cultural common psychological quality and the stability of the community
so,民族 The category of people with common characteristics (national) collection

What is the difference between 人民 and 民族？


If matter is just an illusion what is the source of it

Question: If whatever we see and feel in the 3-D world is just an illusion created by our minds and every matter, even an atom, is related to each other (interrelated); what is the origin of it? Since consciousness or self or "I" is also just a thought, how is matter created by the consciousness? How does the mind create it? Whenever I think of these things, I remember the mythological god, Zeus, who can create anything he wishes just by thinking about it? It feels like this is actually possible. So what could be the possible logic behind this complex knowledge?
Comment: Buddha was against this kind of intellectual discussion about consciousness, rebirth, God etc. He asked people to witness it directly through his teachings. Consciousness cannot be discerned through words. Whether consciousness has created matter or these are two different things is a matter of experience of a Buddha. I suggest you take experiential route than intellectual one. Your existence in metaphysical or physical domain will be revealed to you through his teachings.
Comment: ok, seems like their is no other choice than to do meditate again, to understand this. but i think it would be good if some one would have wrote some book about this kind of things, because it would remove peoples ignorance and material desire/craving as a result world would be more peaceful. cas people dont like to do meditation generally. but if they would have understood its meaning though their intellectual level, how selfishness and cravings results in destruction, atleast by reading some books, than it would be good.
Answer:
If matter is just illusion

I don't think that is Buddhist doctrine. I think that Buddhist doctrine is that we tend to view matter inappropriately or with ignorance.

what is the origin of it

I'm not sure it has an origin. That might be considered an unanswered question. Several suttas (e.g. this one) mention "inconstruable beginning", saying "A beginning point is not evident".

how is the matter being created by the conciousness

I'm not sure that matter is created by consciousness.
But "perception" (of matter) is created when consciousness, matter, and sense-organ come into contact (see e.g. here).
Comment: You may be thinking of the [first and second verses of the Dhammapada](http://www.tipitaka.net/tipitaka/dhp/verseload.php?verse=001), which start with: "All mental phenomena have mind as their forerunner; they have mind as their chief; they are mind-made. If one speaks or acts with an evil mind, 'dukkha' follows him just as the wheel follows the hoofprint of the ox that draws the cart." -- when it's used in that context, people translate *dhamma* as (specifically) "mental states" or "mental phenomena" rather than as (generally) "everything" or "matter".
Comment: Saying "everything is just an illusion created by mind" might be a form of "wrong view", e.g. [on this page](http://www.accesstoinsight.org/ptf/dhamma/sacca/sacca4/samma-ditthi/) the following is quoted as an example of wrong view: "There is nothing given, nothing offered, nothing sacrificed. There is no fruit or result of good or bad actions. There is no this world, no next world, no mother, no father, no spontaneously reborn beings; no brahmans or contemplatives who, faring rightly & practicing rightly, proclaim this world & the next after having directly known & realized it for themselves".
Comment: well than why did buddha said "thought/mind is everything, thought/mind creates everything".
Comment: There's also a (later) "mind-only" or "consciousness-only" school of Buddhism (see [Yogachara](https://en.wikipedia.org/wiki/Yogachara) on Wikipedia); but Wikipedia says that "explains how our human experience is constructed by the mind" (which I think isn't the same as saying that "matter" or "everything" is constructed by the mind) ... or see also [this answer](http://buddhism.stackexchange.com/a/10930/254) which advocates, "treating all Buddhist doctrines as though they are addressing the topic of what we experience rather than what exists".
Answer: The world itself was not an illusion to the Buddha. Rather, given the true nature of experience - Anatta and Anicca, the actions of 'I' making or 'Mine' making facilitate the illusion of a Self, hence the arising of Dukkha. The issue of origin for any thing that lacks a Self, like this existence, is that the beginning doesn't make sense. At best the beginning can't be determined.

"From an inconstruable beginning comes transmigration. A beginning point is not evident, though beings hindered by ignorance and fettered by craving are transmigrating & wandering on. When you see someone who has fallen on hard times, overwhelmed with hard times, you should conclude: 'We, too, have experienced just this sort of thing in the course of that long, long time.'
"Why is that? From an inconstruable beginning comes transmigration. A beginning point is not evident, though beings hindered by ignorance and fettered by craving are transmigrating & wandering on. Long have you thus experienced stress, experienced pain, experienced loss, swelling the cemeteries — enough to become disenchanted with all fabricated things, enough to become dispassionate, enough to be released."
-- Duggatta Sutta

Name and Form arise in dependence of Consciousness and Consciousness arises in dependence of Name and Form. https://suttacentral.net/en/dn15. No 'thing' such as matter is created to be independent. It's like the conservation laws within Physics - 'energy can neither be created nor destroyed, it can only change forms'.
All is possible within conditionality because there is no underlying, essential demarcation line that delineates 'the impossible' from 'the possible'.
Answer: To explain it will take long long paragraph, but still not really explaining anything. To give some orientations relating to your question, first, you said "matter", what is matter? A duck, we say there is a duck (matter), it's shaped a duck-shape, yellow or green in colour, it quacks, it smells, it has soft downs, roasted duck tastes different from chicken. These are all related to our sensory organs: eyes to see (shape & colour), ears to hear (quacks), nose to smell (duck-smell), body to feel (soft downs), tongue to taste (roasted duck); and our mind to recognize all these, without these attributes, does this duck exist? Not sure, we can't say. 'Ok, but there must be something exists for I response to this to form this idea "duck"'. Then, must be the duck if it does exist existing in an absolute form you perceived? Again, we can't be sure. For instance, a colour-blind will see differently from you, at least the duck is not a green duck; further, an animal such as bat who uses sound to see, he will see a different duck, not to mention that Mr. Bat probably doesn't like the taste of roasted duck :)... so on and so forth. Now who has ever seen the "real" duck? We can't determine.
Now you say "for matter what I mean is atom", when saying atom we are still using all these attributes to describe: electrons circulating the nucleus (implied it has a form, no matter however tiny); Ok you say "I mean light", forget the scientist said light sometimes behaved like particle, it's wave, it has/hasn't substance. Well still there is space for this light to "wave", right? In your mind you still have to assume space. Now, are you sure there is space out there? The space assumed existed because you perceived objects - the empty part is space, if you cannot be definite if object exists and existed in exact you perceived them, then the space you perceived is just the negative of the object you perceived, not an absolute. For instance, we can't see air, the space we perceived are in fact not empty, it's filled with air particles, so on and so forth. Einstein said the space is "ether" (Einstein was not definite about this claim), both space and ether, if we have to look at if it existed, we have to use the attributes of our sensory categories and intellect (mind)... thus in however dissecting the "matter", we can't escape to perceive it within our the six categories or their extensions: eyes, ears, nose, tongue, body and mind.
Now not based on our six categories and extensions we can't describe any "matter", further, if the colour-blind, bat and me could be seeing the same duck differently, the only possibility is that all of us are seeing and responding to the illusion of our own construct... that's how illusions can "form" a world. When we say "the world" we are only able to refer to the world in our mind, with thousands minds there are literally thousands "worlds", all are illusions but real to the individual mind.
It will be very complex impossible to at one step to explain all, but you asked a good question. As a student of the Dharma of Buddha with some Sutras I read, I come to realize a bit more. Currently reading Nagarjuna's 《中論》 - absolutely a sheer mind addict, I was laughing with myself like idiot, Nagarjuna has a very cool (cute :) character reflected in his employing of words and manner. I can only say, if you are interested to find the answer, you better study the Sutras. As far as I reckon, those Sutras that answer this kind of questions are mainly in Classic Chinese, not translated. If they do have translations, most of them are not satisfactory. For a translator to be able to produce accurate translation, one must first need to understand the content, not to mention if one is an adept of both languages to correctly communicate the content.
Once you understand, and in realizing the truth how all these are actually working - scientists are going at the opposite direction, then you can also be like Zeus, create anything you wish. When one is truly enlightened, he can also master the illusion; for realizing Buddha-hood, he is able to create - the Pureland of Utmost Happiness is created purely by Amitabha's thinking. Unlike Zeus or Brahma, he began just like us, a normal human being. Further, he spent kalpas of eons to know about the most beautiful and "acquire" the beauty of beauty to create his pureland. Thus it's praised much by Buddha Shakyamuni, encouraging us to try getting a "visa" ;). Nagarjuna left planet Earth (Samsara) for there, it's not sure whether he is a citizen of Utmost Happiness just traveled here for assignment, or whether he has new assignment not staying at Utmost currently. : /
~~~~~
To not be confused is that when I say '"Amitabha's thinking" created the pureland', it's not the same as those understanding Brahma or Zeus creates by thinking. In here Amitabha is more like a great artist who does a splendid painting, and the raw material (matter) is - if you insist there must be "matter" there, conventionally called Emptiness - for it's not a "matter" as our human mind can discern, but it has attributes that we can see in phenomenal world, such as the 4 Greats: earth, water, fire, wind. To make you even getting more at this "creation and matter" contemplation, that this world is created by us too - a collective thinking result, in brief. 'If so why can't I now create an ice-cream by thinking?' Because you don't know how these are in working we can't master the result; further, because of ignorance this ability can't be fully realized, thus we create it blindly, like an unskilled artist doing a very unsatisfactory painting. Now you may see a bit more into how illusion can exist as real, how we are treating like it really does matter there is "matter", on Emptiness. Last, Emptiness is emptiness, so it doesn't need any/anyone-to-do-the creation. :D ~~
Answer: Buddhism does not state the external world of forms, such as the earth, is an illusion created by mind. For example:

It would be better for the uninstructed run-of-the-mill person to hold to the body composed of the four great elements, rather than the
  mind, as the self. Why is that? Because this body composed of the four
  great elements is seen standing for a year, two years, three, four,
  five, ten, twenty, thirty, forty, fifty, a hundred years or more. But
  what's called 'mind,' 'intellect,' or 'consciousness' by day and by
  night arises as one thing and ceases as another.
SN 12.61

Instead, what is an illusion is the mind & particularly the perceptions & thought constructions of the mind.

Now suppose that in the last month of the hot season a mirage were shimmering, and a man with good eyesight were to see it, observe it, &
  appropriately examine it. To him — seeing it, observing it, &
  appropriately examining it — it would appear empty, void, without
  substance: for what substance would there be in a mirage? In the same
  way, a monk sees, observes, & appropriately examines any perception
  that is past, future, or present; internal or external; blatant or
  subtle; common or sublime; far or near. To him — seeing it, observing
  it, & appropriately examining it — it would appear empty, void,
  without substance: for what substance would there be in perception?
SN 22.95

Matter is not created by consciousness. Instead, consciousness is created from matter.

Mind-and-matter (nama-and-rupa) is the cause and condition for the manifestation of the consciousness aggregate.
SN 22.82

It's good, monks, that you understand the Dhamma taught by me in this way, for in many ways I have said of dependently co-arisen
  consciousness, 'Apart from a requisite condition, there is no
  coming-into-play of consciousness.'
Consciousness, monks, is classified simply by the requisite condition in dependence on which it arises. Consciousness that arises in
  dependence on the eye & forms is classified simply as
  eye-consciousness. Consciousness that arises in dependence on the ear
  & sounds is classified simply as ear-consciousness. Consciousness that
  arises in dependence on the nose & aromas is classified simply as
  nose-consciousness. Consciousness that arises in dependence on the
  tongue & flavors is classified simply as tongue-consciousness.
  Consciousness that arises in dependence on the body & tactile
  sensations is classified simply as body-consciousness. Consciousness
  that arises in dependence on the intellect & ideas is classified
  simply as intellect-consciousness.
MN 38
Answer:
If matter is just an illusion what is the source of it

The source cannot be found. One has to become a fully enlightened Buddha to be able to gain knowledge about its origin.
Physical matter is not an illusion but rather like an illusion as it is empty of solidity, permanence.
It exists in context of our experience.
In reality what is percieved as matter is really just the sensitive quality of the eye connecting with its corresponding object, i.e. light, visible forms, which allows eye-consciousness to arise. It's just an impersonal process.
This in turn gives rise to a mind-door process, a reflective process of what has been just been seen. The process can be stopped before the mind-door process begins, by guarding the sense doors, i.e. by noting the seeing, thereby keeping the mind in the present moment, free from judgements, extrapolations, liking, disliking of the object.
The very idea that we live in a 3-dimensional world is just an extrapolation, an interpretation, a mental formation belonging to the 4th aggregate of mental formations - these too are subject to the three characteristics of impermanence, unsatisfactoriness and uncontrollability that defines all conditioned phenomena.
What exists is experience. Right now I can see the computer I'm using to write this post. There is definitely a seeing going on. But there is no seer. The idea of a "seer or an I" is just a mental formation.

How do mind creates it?

Its a complex process but it is visible and verifiable through the practice of insight meditation. By observing the mind with objectivity one can see how it works. When non-interference is present the mind will reveal its mechanics to the observer.
The problem arises when one is not mindful of a sense object impinching on the sense doors, e.g. the "idea of a 3-dimensional world".
When one is not mindful of a sense object the mind will only for a brief moment apprehend the true nature of the object whereafter it begins a cognitive process of mental fabrication in order to try to grasp the object. The mind will take the "raw material" of the object and thereafter bring forth subjective concepts and ideas about the object.
The mind then weaves together all these different concepts into more complex structures. These are embellishments fabricated by the mind and does not belong to the object. They are added to it.
It's the mind superimposing qualities onto the object. This process of fabrication is fueled by the underlying latent defilements. The end result is an object which is now covered with a thick layer of mind-generated ideas and qualities. The original object is now hidden in a dense layer of subjective extrapolations that hides its true nature.
As mentioned earlier this subjective process can be avoided by guarding the sense-doors. The key is practice instead of intellectualization.
The Buddha was often asked questions such as whether or not the world was finite or infinite. When asked such questions he always brought the questioner back to practice.
Answer: Certain subjects are declared to be imponderable by the Buddha:
1) range of powers of a Buddha
2) range of powers obtained while absorbed in jhana
3) precise working out of the results of karma
4) speculation about the origin (the first moment, purpose, etc.) of the cosmos
The -origin of matter- question seems like it probably is the fourth imponderable.*
WHY TEACHERS WON'T ANSWER QUESTIONS
Beginning meditators start with simple concepts but too often we want to leap ahead and open the Christmas presents before Christmas, so to speak.
Wrong view in the path is like when the meditator believes they already understand "Sila" and "Dana"  and what seems most useful , to this certain student, is to learn the juicy bits... the exotic stuff, like anatta and Dependant Origination. This is a wrong view festival.
The reason why teachers don't explain certain advanced concepts is because most likely an intellectual understanding leaves too much room for interpretation so that there is too much danger that the student will develop  wrong view.
Your mindful experience is what will teach you. If you are a practicioner, it's best to get a good teacher that can really give you the right information at the right time that you need it.

THE FOUR IMPONDERABLES:

http://buddhist-spirituality.com/suffering-end/the-eightfold-path/right-thought/four-imponderables
Answer: In the Buddha Dhamma, the human being is an impersonal combination of ever-changing mind and matter. In the flux is found no unchanging soul or eternal principle. The self or soul is then a piece of fiction invented by the human mind. To believe in such an absurdity is to create another source of unhappiness. One should therefore see oneself as one truly is — a conflux of mind and matter energized by tanha or craving, containing immense possibilities for both good and evil, neither overestimating nor underestimating one's capacities and capabilities.
Aggregate of Matter or Form (Rupa) corresponds with material or physical factors. It includes not only our own bodies, but also the material objects that surround us – the earth, the oceans, the trees, the buildings, and so forth.
Specifically, the aggregate of form includes the five physical sense organs and the corresponding physical objects of the sense organs. These are the eyes and visible objects, the ears and sound, the nose and smell, the tongue and taste, and the skin and tangible objects. Mindfulness, which puts full attention on the movements and the characteristics of the body, can eventually see with clarity that the body is nothing but a conglomeration of parts. Mindfulness of this will help one to lose some of one's attachment and ego illusion about the body.
To get to know "Nama-Rupa", and the 'fiver skandhas"  the following dialogues between King Milinda and Arahant Nagasena is helpful.
Venerable Sir, what is 'rupa' and what is 'nama'? Why do they generate together?

Dear king, 'Namarupa'  means mentality & materiality.   Mentality (mind & thoughts) is 'nama'. Materiality (the four great elements 'Patavi', 'Apo', 'Thejo', 'Vayo' which are transitory and the material form derived from them) is 'Rupa'. 'Nama' and 'rupa' are linked together like flowers and their scent. They are born together. This phenomenon has been there for a long time.

Venerable Sir, what does conceive as the birth?

Dear King, 'Namarupa'  (psychological elements of the human person & physical body / Mentality & materiality) conceive as the birth. The body & mind we have at present would never be reborn. Because of the results of good and bad deeds (Karma Vipaka) which we have done using our mind and body, another 'Namarupa'  (psychological elements of the human person & physical body) is conceived.

Venerable Sir, is it the materiality or form (Rupa) which is Nagasena? Is it the feeling or sense (Vedana) (pleasure, pain or the absence of the either) which is Nagasena? Is it cognitive perception (Sanna) ( awareness of colour, shape, sound, smell, taste & touch) which is Nagasena? Is it volition or mental formation (Sankhara) (habitual actions like greed, hatred, generosity, kindness…etc) which is Nagasena? Is it consciousness (Vinnana) (all the mental faculties pertaining to perception & experience) which is Nagasena?

None dear king.

Venerable Sir, Then is it the five aggregates (Rupa, vedana, sanna, sankhara,  vinnana) which is Nagasena?

No dear king.

Then, who is Nagasena?

Dear King, you came here by a chariot. Do you call the compartment the chariot? Or, do you call the roof the chariot? Is the cart wheel or the beam the chariot ? Is the axle the chariot ? Is the bridle the chariot ?

No Venerable Sir.

Dear king, when the compartment, the roof, cart wheels, the beam, the axle and the bridle is combined, it is called the chariot. If it is dismantled and heaped, nobody would call it a chariot.
Similarly, when my hair, teeth, nail, skin, flesh & bones are together, it is called Nagasena. When the five aggregates are together, it is called Nagasena. But, in reality, there is no such person.
Our Great Buddha said thus to Bhikkuni Vajira : "In the manner, that a chariot is called a chariot when the cart wheels, compartment, axle, beam, etc. are combined; a being is called thus when the five aggregates (the Five Skandhas)are merged. "

King Milinda was very happy about the explanation and thanked Venerable Nagasena.


How about list questions?

Question: How should we feel about list questions? For example, there's already How can I protect equipment against a lightning strike? which seems to beg for incomplete answers at best (because I doubt anyone is going to sit down and list everything one can do to protect their radio equipment against lightning strike in a single answer), and is a shopping recommendation question at worst. In fact, there's already an answer on it that takes it from a shopping recommendation point of view.
Answer: I don't think it's possible to completely ban "list questions" simply because the potential meaning of "list question" is so broad as to cover a lot of things that probably could get quite a useful response out of the Q&A format. (You could ban a narrow definition, e.g. questions that specifically ask for a list, but that only affects a small subset of questions.)
If you restrict questions to only those which have a single empirically correct answer you tend to wind up with a site that ignores practice and focuses solely on theory, because only in theory do you really ever wind up with one clear "right" answer.
I think it would be better to focus on creating a community that avoids list answers and leaving the focus on questions to be whether or not they are too broad.
Comment: Yeah, I'm just saying that there's going to be some subjective judgment that goes into what a "list question" is (just as there is for broadness). Otherwise, I totally agree.
Comment: List questions are generally considered to be "too broad" on Stack Exchange. And it seems to work pretty well on other sites, including what I think we should consider our sister site [Electrical Engineering](http://electronics.stackexchange.com/).
Answer: No. Q&A is not the right format for list questions.
To quote the relevant part from this answer on Meta.SO

Generally, those questions are infinite, as a new answer could always be added; they also tend to be subjective. As such, those questions should not be asked, basing on what written in the FAQ.
Comment: Correct answer, but the lightning protection question is not necessarily a list question. There is only a finite amount of possible answers and a clear consensus that the only sure way is to unplug your rig. This question also has safety significance.
Answer: If have seen many list questions and answers on other SE site that worked and keep on working very well.
Here is a nice example: "Comprehensive list of tools that simplify the generation of LaTeX tables."
For this reason, I am a fierce proponent of open-ended list questions.
Not all useful information in the world can be poured into closed-form answers.
Furthermore, the idea of constantly editing to improve existing answers and adding new and better answers forms an inherent part of the philosophy of SE.
Examples as the one above demonstrate that this does not need to end in chaos as long as the question contains orchestrating instructions. A little editing of the original question by experienced SE users may help in such cases.
Finally, a topic as ham radio inherently generates less questions and answers than a broad SE topic such as, for example, computer system administration. It is not so  (yet?) that our gear spits out error messages one after the other. SE as a company has not yet entirely grasped this inherent difference. See also "Is Stack Exchange vetting historically biased towards topics about syntax and semantics?" Therefore, it is in our interest to allow list questions and answers in order to pass our public beta minimum traffic requirements.
Comment: *"Not all useful information in the world can be poured into closed-form answers."* -- The goal of StackExchange is not to index all useful information in the world.
Comment: @Amber You are logically inverting my statement. I did not say that our goal is to index all useful information in the world.
Comment: I didn't say you said that. However, there's not much reason to mention a fact about "not all useful information" if the implication isn't that we need to do something for all useful information.
Comment: Furthermore, no, we are not going to adjust our question vetting process simply to pass traffic requirements. That defeats the spirit of the requirements, not to mention working at cross purposes to many of the other requirements aside from traffic.
Comment: @Amber If you would read the above-referenced meta discussion carefully, it is neither you nor I but SE as a company that does the vetting between SE proposals and betas...
Comment: I'm referring to the process of vetting questions, not sites.
Comment: In [this specific case](http://ham.stackexchange.com/q/882/29), the instructions in the question would lead to a situation where the number of answers does indeed grow unbounded pretty much until Ethernet falls out of favor, and it won't necessarily help with the stated goal because there are many ways other than an Ethernet port to accomplish remote control and operation of a transceiver. A 1 ½ years old question on another site does not necessarily make the practice more appropriate.
Comment: For one thing, on what criteria would people vote on answers ("yes, this model really does feature an Ethernet port"?), and on what criteria will you pick the answer to accept? I know myself that it isn't always easy to pick a single answer to accept, but in this case, one answer cannot possibly be more useful than the others. If I'm looking for a piece of equipment (ham-related or not) with a specific feature, I'll either use a favorite search engine to try to locate it, or ask a retailer which models may be of interest to me and then investigate those further.

How about list questions?


How does ecommerce tracking work for multiple currencies

Question: I have a client based in the UK which sells from one website to multiple countries. I am setting up standard ecommerce tracking through GTM and wondering, if someone pays in USD, will GA recognise this and convert to my default currency GBP?? If not, does standard ecommerce recognise currency as a dataLayer variable??
Answer: I have come across an article which explains how to set this up in GTM as it is not currently supported:
https://grantlucas.com/posts/2016/12/setting-currency-when-using-universal-analytics-and-google-tag-manager-ecommerce


How does one create a non-classifying CNN in order to gain information from images?

Question: How do I program a neural network such that, when an image is inputted, the output is a numerical value that is not the probability of the image being a certain class? In other words, a CNN that doesn't classify. For example, when an input of an image of a chair is given, the model should not give the chance that the image is a chair but rather give the predicted age of the chair, the predicted price of the chair, etc. I'm currently not sure how to program a neural net like this.
Comment: I'm confused. Are you talking about a regression problem?
Answer: This can be thought of as a loss function design problem. If you optimize your network weights for something like multi-class classification, then expect your network to learn weights for this task (You will use cross entropy loss for this task). If you optimize your network to output a single value at the last layer and treat it as a regression problem for age prediction, then your network can learn weights for this particular task (You may use something like Mean Square Error loss here).
Let me give you a weak guidline on how to do this. Suppose say your input is images of chairs and you want to predict their age using a pretrained resnet, this is how you may do it in pytorch.
Definition
X: Input pictures
Y: List of ground truth values which is age here. i.e. : [1.4, 2.5, 2.2, ....]
Modify your neural network to give one output at the last layer
model = torchvision.models.resnet18(pretrained=True)
num_ftrs = model.fc.in_features
model.fc = torch.nn.Linear(num_ftrs, 1)
Design your loss function appropriately. You can treat age prediction as a standard regression problem. Of course, there are better loss designs here.
criterion =  torch.nn.MSELoss()
So use this loss during training
loss = criterion(output, target) where output is your neural network prediction and target is your ground truth values.
This is how you can modify an existing architecture for your task. Hope it helps.
Answer: You generally use SoftMax Layer as the output layer for a neural network that is used as a Classifier.
Now, if you want your neural network to predict the age of a chair, predicting price of a chair like in linear regression (output is continuous), you have to remove the SoftMax Layer and add one or multiple layers such that the output of the final layer gives only one value at the output. (which is the prediction for you age or price). And, instead of logit loss you can use MSE for back propagation.
So, like keshik mentioned in another answer, it's all about the final layer used and the loss function used. Based on what you use, your weights get trained.
This is what is done in transfer learning also. Based on the task you want to achieve you change the last layers and retrain your network.


Why did the writers of Blake's 7 destroy the Liberator?

Question: The Liberator was a beautiful ship design with good sets and an interesting computer (Zen). My question is not why it was destroyed in-universe, but why the writers decided to get rid of it. Was it too powerful? Did they have to dismantle the sets for some reason (cost, perhaps)? Did the new producer try to fix things that weren't broken? Did the voice of Zen choose to leave the show?
Answer: Terminal, the final episode of season 3, was originally going to be the end of Blake's 7 (this is why Gareth Thomas was persuaded to reprise the role of Blake for the episode, which of course happened again for the real conclusion).  The destruction of the Liberator was a suitably dark ending to the show, and the real set was used for filming its destruction (March 7th, 1980).
The end was so certain, that when the episode was broadcast (March 31, 1980), the cast and crew had already dispersed.  Most of them didn't even know that there would be more episodes until this was announced during the credit sequence at the end of Terminal.
The story (according to the Blake's 7 Summer Special for the final season) is that the Head of BBC Television was impressed by the episode and instructed (while it was airing!) that an announcement be made during the end credits that the series would return.
At this point, there were both in-universe (it was a fairly definitive destruction, unlike the destruction of the 'sister ship' in the first season, and this was stolen technology was more advanced than most, so not easily repaired/rebuilt) and out-of-universe (the set was blown up!) reasons to need a new ship, rather than a repaired/rebuilt Liberator.
Peter Tuddenham voiced both Zen and Slave (the computer of their next ship, Scorpio), and also Orac, who survived the Liberator's end.  Since he was already continuing as Orac, it made sense for him to do the voice of the new ship as well (and Zen and Slave's characters were sufficiently different that it wasn't especially obvious that this was the case).
Comment: +1 for this - I don't have any canonical references, but it's pretty obvious that Terminal was supposed to be the end, and series 4 was an afterthought: different ship, Servalan no longer president...
Comment: I think this was mentioned in *You're Him, Aren't You* (Paul Darrow's autobiography) as well, but I only have it as an audiobook, which is tricky to search through.
Comment: A piece of additional information. As stated above 'Terminal' was to have been the final episode. But during the series transmission the BBC realized that they had nothing to replace it with, as the new drama they were developing was running way behind schedule and would not be ready for it's proposed broadcast date. Blake's 7 was very hastily recommissioned. Allegedly, several members of the cast and crew only found out there would be a new series on hearing the announcement at the end of 'Terminal'!
Answer: The destruction of the Liberator (in the context of Terminal being the final episode at the time) provided Nation with  with the opportunity to give Servalan what she has been seeking for the entire series...but only for a short time.  Servalan's desire for the Liberator can be argued as being the main story arc of Season 3 and this is arguably one of the reasons why many see Season three as weaker than season 1 or 2 as there was no real story arc for the heros. It is even mentioned on the DVD commentary that when Tarrant says to Vila "Can't always have what we want now Villa..." that this is the main theme of the episode.
Here we see the obsessed Servalan seizing control, gloriously commanding "maximum power", only to have her whole prize disintegtrate around her. The destruction of the Liberator therefore becomes one of the strongest symbols of irony in the (entire) series.
Avon's smile at the end is also such a symbol of irony.  Throughout season 1 and 2, Avon had tried frequently hinted that he wanted the Liberator, "I am free, I intend to stay that way", "....I will take you back to earth then the Liberator is mine, agreed ? " even proclaiming "This is MY ship" in Powerplay. In Terminal, Avon is tricked into believing that Blake is alive, he falls into the trap, based on Servalan's conditioning about Blake.  "You wanted to belive Blake was was alive" and yet, in his persuit of Blake, he looses the one thing that he managed to win from Blake in the first place.....
The destruction of the Liberator therefore provides Ironic tradgedies to both hero and villian and was a stroke of genius from Nation.
Answer: A Blake's 7 magazine of the mid 1990's said that makers were influenced by the film Alien, which they found darker and a more grim reality.  They thought Liberator was too glamorous.
Though some of the Alien films are quite good, Blake's 7 is superior, and should never have sought to copy something inferior.  Best regards.  Steven Summer, of the Blake's 7 obsession website.
Answer: I saw in an interview, it was for one simple reason.  The set was falling apart.  If it was not broke, it was stolen by visitors to set.  Limited wrist bracelet and guns.  So they started over.
Answer: Very simple, everyone associated with the show thought that 'Terminal' would be the final episode of the series. Therefore, they destroyed the Liberator sets in one massive finale.
Comment: This adds nothing to the accepted answer.
Answer: I read somewhere that the technology of the federation was catching up with that of the Liberators.And the new persuit ships that Servalan had nearly caught them in a trap .Not sure of the episode now, mentions the new persuit ships,so Blakes crew where going to have to upgrade soon anyway,which they got in Stardrive.The photon drive or Stardrive was fitted into Scorpio.
Which makes sense ,everything is oudated sooner or later.


Why use SafeMath library?

Question: I read that whenever you are performing arithmetic operations in a function of a smart contract, you should use SafeMath library. What is the reason for using SafeMath library? Also, what are the advantages and disadvantages of this library during arithmetic operations?
Answer: Safemath library is useful for prevent integer rage overflow or underflow after integer operations. Its very important because it will impact user data or global ERC20 or any token value. Resultant your token will returns unexpected results. You can't update existing contract.
If you write extra statement in ethereum that consumes gas for steps. i.e it consumes eth. When compare to advantage's this is negotiable.
Answer: Advantage: if there is a 256-bit overflow in the computation, then the operation will be aborted with an exception, and all preceding changes in state (global) variables will be reverted.
Disadvantage: cost slightly more gas for each operation.

Why use SafeMath library?


What are the scalability benefits of PoS vs PoW?

Question: This accepted answer claims that one advantage of PoS vs PoW is that
<code>some scalability problems can be addressed more easily with PoS
</code>
What are those scalability problems? What are the scalability benefits of PoS vs PoW?
Answer: An obvious way to scale a distributed database is to put transaction types that will never rely on each other into two separate databases. This is such a standard practice it's difficult to find a citation for it. But if we are using a PoW blockchain to store our data we cannot do this because the smaller shard will be less secure in proportion to its size when compared to the larger chain. Let's say we split bitcoin into BA and BB. BA has 90% of the hashpower BB has 10%, that means it will take only 5.1% of the total hashpower to control BB. As it stands, no one has provided a solution to this; personally, I don't think there is one.
Since the security properties of PoS are not based on the extrinsic cost of validating the chain, the above attack is out of scope and we are free to shard/scale the network in a more traditional way.
Comment: "I don't think there is one" -> Is your research/ideas online?
Comment: Sadly, a lot of it is correspondence that occurred in person. Feel free to chat with me, i'm not hard to find :D
Answer: PoS has more energy efficiency benefits, the amount of electricity needed to process the blockchain is greatly reduced. Also the probability of 51% attack will be decreased because it means having a vested stake "balance" within the network so attacking the network would not be in the users best interest since they will have to own 51% of the network to attack it. Network nodes should generally increase leading to greater distribution and a higher amount of security, nodes need to be online in order to stake blocks this is what will cause this increase and thus meaning the network is more distributed and secure. I would also argue PoS is better for ease of use since it does not need mining software or appropriate hardware.
Comment: Which part of your answer addresses scalability?
Answer: So for Scalability, it's much easier to handle in terms of speed because it's easier to see who has what amount of the crypto than it is to see hashing power and to come to a consensus on this. There is also the aspect of that it's just plain faster. Ethereum is one of the fastest proof of work algorithms out there that is still being utilized, and even it currently gets smoked by PoS algos like Bitshares in terms of pure speed. Hence why Sharding + POS is becoming more of a need than a desire for simply being nice to the environment. In terms of block sizes and storage and state, there's really not much else to that...POW and POS are virtually the same in this aspect. So in the long run, PoS becomes much more of a necessity as the need for more transactions increases.
Answer: PoS can essentially eliminate the problem of needing the processing power and the energy to finish the PoW algorithm. As for the 51% control of a network PoS if anyone stakes the highest in the network they won't be able to control it. If they were supposed to validate a fraudulent transaction they would lose their stake as well as the ability to validate in future. It is also counterproductive for any individual to buy more of the cryptocurrency to gain more stake as the more cryptocurrency they buy the more expensive it will be. Overall PoS seems to be a better solution as it will make the blockchain safer, drastically reduce its power consumption, and reduce the time it takes to make transactions.
We had wrote about an article to explain the differences between PoS and PoW. You may refer to this link to see the full article. https://www.dapp.com/article/proof-of-stake-or-proof-of-work-whats-the-difference


Calculating how secure my password is

Question: I generally use GnuPG for encrypting my files and as far as I know its strength ultimately depends on the passphrase I use. So, I would like to know: how can I mathematically calculate how secure my password is? How do I know whether my password is safe or not?
Comment: There has been a good discussion on password strength  http://security.stackexchange.com/questions/6095/xkcd-936-short-complex-password-or-long-dictionary-passphrase you can have a read
Answer: The strength of a password is, exactly, a measure of what it could have been. The technical term for cryptographers is "entropy". The rough idea is the following: there is a set of "possible passwords" -- the passwords that you could choose. The attacker will try the passwords from that set. The attacker will be defeated if the set is large enough, because the larger the set, the longer it will take the attacker to hit the right password (on average).
For instance, if your passwords are sequence of 9 decimal digits, then the set of possible passwords has size, exactly, one billion (109). If you choose your password at random in that set, then, on average, the attacker will have to try half of the set before trying yours, so 500 millions.
Thinking about a big bag of possible passwords from which you choose, at random and uniformly, works as long as you really pick the password at random and uniformly. That's easy to do with a computer, very hard with a brain: the jelly which you keep inside your skull is remarkably good at a lot of tasks (such as image recognition), but not at randomness.
The important point to understand is that password strength comes from the password generation process. A given password is not strong "by itself". That's where "password meters" totally fail. A "password meter" sees only the password you type, not how you chose it. If you prefer, a password meter site will tell you how much time it would take an attacker to guess the password, assuming the site is the attacker, and knows nothing else about you. That's not completely realistic: your enemy knows you, much better than a lambda site on the Web. He is after you, specifically, and he must be assumed to be smart.
So, to estimate your password strength:

If you generated the password in your head, then try again: it is weak. From now on, I assume that you produce the password with a random generator (a computer with <code>/dev/urandom</code>, some dice, coins flipped... the choice is large).

Compute the size of the set of possible passwords, depending on your generation algorithm. For instance, if you use a 20-sided die to generate symbols (letters from A to T), and you launch the die 8 times, then the set of possible passwords has size 208 = 25600000000.

Estimate how many passwords the attacker may possibly "try". This is where the encryption details matter. GnuPG follows the OpenPGP format in which passwords are converted to keys through a hashing process which is intrinsically slow, in a configurable way (see section 126.96.36.199 of RFC 4880). This is expensive both for you, and for the attacker. The attacker has several computers which are bigger than yours, so he will be able to try a lot of passwords, but not ludicrously many. As a rule of thumb, consider that the attacker can try no more than one million passwords per second.

From the two previous steps, compute how much time it will take for the attacker, on average, to crack your password. On average, he will have to explore half of the set of possible passwords. With the numbers above (8 symbols from a 20-symbol alphabet, one million password guesses per second), you find 12800 seconds, i.e. a bit more than 3.5 hours. That's not much for comfort... but each additional symbol multiplies the attacker effort by 20. So 10 symbols with your D20 bring the attack time to about two months, at which point the attacker ought to declare that it is "not worth the effort" (which is your goal).

Hence the rules for strong passwords:

Don't trust your brain. Generate the password with a computer or dice.
Accept the generation result. Don't generate passwords until you find one which seems "easy to remember".
Stick to symbols which are easy to type. In particular, a sequence of lowercase letters is easy on a smartphone. Mixing cases, digits and punctuation symbols makes the password usage frustrating.
Use sufficiently many symbols so that the set of possible passwords is large enough. This depends on how well (or how badly) the encryption system hashes the password into a key. Unless the encryption system is tremendously incompetent (in which case you should not use it at all), 12 or 13 letters will be enough (do the math !).

In the famous XKCD password comic, the author suggests taking a list of 2048 "common words", and then selecting four such words (at random, with dice): the four words, concatenated, will be the password. The set of possible passwords then has size 20484 = 17592186044416, which is quite good. The point of the author is that such passwords are easy to remember (whatever the four words you obtain, you will find a corresponding "story"). Personally, I prefer shorter passwords which are just random letters (my brain, being that of a mammal, is bad at randomness, but it is quite good at remembering strings of symbols).
The key to remembering a password is to type it daily.
Answer: http://www.passwordmeter.com/
For security reasons, don't enter your real password, but an approximation, for example, if your password is asl6234FDS, type ajk0175MAF. Strong password has a score of 100%.
Comment: That tool is really bad. It wants you to use special characters, is all. [Special characters don't make a password better](http://security.stackexchange.com/questions/6095/xkcd-936-short-complex-password-or-long-dictionary-passphrase/6096#6096).
Comment: Thank you for the link. But I would like to know a method so that I can calculate it myself.
Comment: Look at the rate column. Also, it's JavaScript, so you can look at the source code.
Comment: `BadPassword12` gets 83%, this is a good tool and gives a nice breakdown, but scores a little too highly imo.
Answer: To calculate how strong your password is by yourself you must first understand how a an attacker might 'crack' it. There are three main ways:

Dictionary attacks
Hash Tables
Brute forcing

Now assuming your password is 'strong' (i.e. is random long and uses lower case, upper case numbers and symbols), then the attacker should be limited to brute force attacks, so I will limit my answer to this.
Brute Forcing means that the attacker will try every possible password. To keep things simple let's say your password is only 1 char long, and only uses lowercase alpha chars (i.e. the alphabet). This means that the attacker would start at a, then b, c, d, ... z. Now there is 26 letters in the alphabet, which means if you only have a password 1 char long and lower case, they must make 26 guesses (and on average they should crack the password halfway i.e. 13 guesses). By introducing uppercase you double this, (i.e. it will on average take the attacker 26 guesses, or in other words, it will take the attacker twice as long). Adding numbers and symbols will also increase the number of guesses, and hence the length of time needed to crack the password.
By adding a second character (i.e. a 2 char long password), the amount of passwords the attacker has to guess is exponentially increased.Once again to keep things simple let's study a binary password (i.e. it can only have 2 chars 0, or 1):
For a 1 char password the possibilities are:

0
1

This is 2 passwords, for a password of length 2 the possibilities are:

0
1
00
01
10
11

There is now 6 possibilities.
Therefore to calculate password complexity you need to consider two things:

The amount of different chars used (upper, lower numbers, and symbols)
The length of of chars used.

Calculating how secure my password is


if I replace chainset and chain should I replace back cassette as well?

Question: I am replacing my chainset and chain, as its totaly worn and causing the chain to jump off when I pedal. The cassette is fairly worn too, but is not causing any problems. If I buy a new chain and chainset will these wear out a lot quicker if I leave the old cassette on?
Comment: See also: [Do I need to change my cassette if I can't see any wear?](http://bicycles.stackexchange.com/questions/2824/do-i-need-to-change-my-cassette-if-i-cant-see-any-wear)
Answer: You'll probably need to replace the cassette as well.
Generally once the chain has worn ("stretched") a little, it starts to wear down all the gears (front and back) that it touches. If there's enough wear that the front chainrings need to be replaced, it's almost certain that the gears on the cassette that you use most are also worn enough to need replacing. Usually the gears on the cassette will wear faster than the chainrings simply because they're smaller (so each individual tooth gets more wear).
The new chain will wear faster if the cassette is worn out, but a chain is generally cheaper to replace than a cassette. It should only wear the chainrings if you let the chain wear go.
You can look for signs of wear on the cassette, it will mostly be in the form of the teeth being thinner, often with a sort of "shark fin" appearance (sloped on one side). It's likely some gears (your favorites) will be worn more than others, which can give you something to compare against. If you can see signs of wear you should replace the rear cassette.
If you replace the chain and chainrings but not the cassette, I suggest paying very careful attention to how the chain runs when you first put it on.  If there's any kind of roughness to how the bike pedals, any kind of noise coming from the rear end when you pedal, or problems with shifting the rear, then it's probably time to replace the cassette.
Another thing you can do if you keep the old cassette is check the chain for wear regularly. If the chain wears down ("stretches") faster than it seems like it should, replace the cassette.
Comment: @Colin Newell, that's pretty true. They need to wear together, An old cassette on a new chain will force the chain to wear very quickly, once it is beyond a certain wear point, and eventually that newly worn chain will similarly damage the chain rings. Unless the cassette is very nearly new when you replace the chain rings and chain, then it should probably be replaced. The cassette is still damaged, even if it's not yet slipping, and will shorten the life of the rest of the drivetrain.
Comment: cheers thats a great help!
Comment: to tell the truth I don't think you'll have much difficulty spotting a problem.  A lot of the time when you fit a new chain and not a new rear cassette you'll get chain slip so it'll be really obvious very quickly that the old cassette isn't working with the chain.  I'm not even sure that a cassette has to be completely worn out for that to happen, I think it's more a case that the two parts simply haven't mated properly (and never will).
Answer: First off, a good bike shop will have a tool for testing the wear on the cassette.  Generally the rear sprockets wear out about twice as fast as the front, so the cassette is probably due for replacement if the front sprockets are gone.
After you replace the chain, you may notice that the chain and cassette "don't get along" very well together, with the chain tending to skip, jerking, not shifting well, etc.
Riding with the old cassette will likely cause the chain to wear faster, but not by much.  Should not cause any untoward wear on the front sprockets unless you let the chain become too worn.
Comment: Can you link to that tool, please?
Comment: The one I saw was not identical to the one in the link, but quite similar.  Basically you wrap it around the sprocket, engage the end of the lever in a sprocket tooth, and tug lightly on the lever, while attempting to lift the other end of the chain.  If the chain end lifts easily then the sprocket is worn, and how many teeth you can lift it off gives a measure of the wear.  Probably requires a degree more "interpretation" than a chain wear tool -- one would want to try it in several different circumstances before trusting it (and your use of it).
Comment: Thanks, I've been looking for something more definitive than, "It looks worn to me."


How can we handle users that continually copy paste answers without citing a source?

Question: I understand that the best course of action is to add a source for a particular question.  Is there a stronger way to encourage users to cite their sources in answers beyond down-voting factually correct but copied answers?
Comment: I would also want to highlight plagiarised content in tag-wikis as well.
Answer: Simply copying information, word by word or big chunks of it, without citing the source is wrong.
I don't care how you see it or what license the information is shared from.
You should work the information that you obtain, adapt it and fit it to the needs of the site, after you did that you should add a link to the information you based your post on as the source.
Answers that are exact copies of information from other sites should not really exist in a good context, if you can edit them and make some use of that information great, else they should be flagged for moderation and possibly deleted.
Users that continuous paste information from other sources as their own answers will be warned and possibly have their accounts suspended.
Comment: @Mitch A simple out of context block quote from a site is not an answer, that was the main point of the comments I sent to you, the information should be copied, should be adapted to fit the site as an answer and the source of the information should be always included in any answer you create based on another source.
Comment: Whether or not it's good to use blockquotes for anything but quoting should perhaps be asked as a separate question here on meta...
Comment: @AnwarShah you need to quote the source. If you copied something those words are not yours and the correct source should be quoted at least. Don't make the site a field of copied information from the internet, we should be trying to improve the internet, don't copy the bad examples of internet usage!
Comment: @AnwarShah Isn't that a dupe question already? I'd flag it as such.
Comment: Copying in one's own words constitutes paraphrase plagiarism. You still need to cite unless you thought of the answer **yourself**.
Comment: What about answers, which i gave to serveral questions, thinking they may proved useful. Is it correct?
Comment: I was asking what is the case, if i give my words in several answers. though i try to link to that also, sorry for not being clear first
Comment: @BrunoPereira you said to "Copy the information from the website linked and place it here using your own words." to me that is plagiarism.  So by linking the site, and using block-quote for the information copied is the way not to plagiarize.  Right?
Comment: @mateo_salta, it was just for formatting
Comment: @mateo_salta Oh, I never thought block-quote is for only quoting, i used them for formatting. I also edited some to look good with block-quote. is it bad?
Comment: I'm not sure, it was a bit confusing. I thought it was just for quoting. could be wrong
Comment: @EliahKagan I am sure that was already discussed millions of times :/
Answer: I do that sometime.  Reason, I don't know much about Ubuntu, and Linux fro that matter, and I know that is not an excuse.
The first rule of copying information from a location to another is to identify the owner.  By doing so it is not considered plagiarism.  Now copying and changing few word, is still called plagiarism if you don't cite your source.
I try to be Conscientious about what to copy and include the site that it was copied from, just to avoid such a dilemma.  I sometimes go back to plagiarism.org in case I get worried about something, and I try to research it.  Sometimes I even ask the professors at the university that I work at on how to copy information, and use it without committing plagiarism.
Bruno Pereira said in his answer "Plagiarism without citing the source is wrong"  well if you cite the source is not plagiarism, you are merely copying the words verbatim.
Don't miss understand me I agree with Bruno Pereira, you should try to put thing in your own words, but that doesn't relieve you from citing.  You still have to cite the source (website) and sometimes that author or creator of the information that you are trying to use.
I hope that all of us here would work in harmony, and help each other in any way we can if possible.  I remember asking a question about down-voting earlier, and it was closed as being a duplicate,  I looked at that question, and one of the answers said " votes are anonymous, so you should not have to reveal your identity when you down-vote" Gilles.
I agree with that, but there should be an option of multiple reasons that you can choose from, and I think that may help that person to improve his question/answer.  I don't know maybe I went off on a tangent here, but lets all work together as one.
Comment: We do not care much (that's my personal opinion) where the information comes from. What needs to happen is that the information is explicitly added as an answer and that the source of the information is quoted in the answer. You can use quotes from the source at your will, but an answer should not be only a quote from a random site and a link to it. Main reason for that? When the link dies the answer becomes totally worthless and should be deleted. If you use the information obtained, transform it to an answer that solves an issue and quote the source, there is nothing wrong.
Comment: Don't be sorry,  As I said, I have no problem in learning.  I really love Ubuntu, and I'm willing to do it, I just might need help sometimes.
Comment: @Mitch Don't worry m8, I think we are all confusing 2 things here: 1 is low quality posts with a link and a quote that might go bad in a few months, the other is plagiarism. I think some of your post can be fitted in the first case, and none of them in the second. This all question just came on a same day that I commented in a question from you, that's all, don't think it all fits in your case. Keep up and try to improve your questions, thank you for your effort and participation on the site.
Comment: @mateo_salta I don't think I'm the only one doing this, But, to point someone in the right direction, is better that making them fall off. I can give you answers about windows all day long, and I will do it from my head in my own words, why? because I have been using it for over 20 years, but only 2 months Ubuntu. Once I'm more comfortable, I can assure you that answers will change.P.S. 14 out of 225 isn't bad :) I'm pretty sure that when you all started, you didn't become good at it, it took time. Thank a lot for this great discussion, cause that's the way things get better:) I really mean it
Comment: Well, that's OK.  Once I'm more into it, my answers will improve, and I let them speak for me. By the way nice picture (great job). I'm the glass half full kinda of guy.  Hope you have a good day, or night. :)
Comment: @mateo_salta  By the way, thanks for the edit.  I would like for you to take a look at this.  I know the question is closed, but do look at the answer, that just edited, and let me know if its better. http://askubuntu.com/questions/152965/is-there-a-way-to-reset-windows-xp-administrator-password/152969#152969
Comment: Sorry, If that came out a bit too direct, There are some where you quoted where I think they are acceptable, aka software recommendations where you quoted the description of the software, but also give them a bit from you how you use the software, or think it might meet their needs. Or If the user wants an "expert" why on a question, other wise I try to test, reword, simplify, and explain possible pitfalls that the original source might have missed, and cite where the information originated.
Comment: I appreciate what really happened, because you really brought up some really good points, and I agree with you completely. And as a said, I will do my best form now on to come up with better answers, and try to work on the old one, and try to improve them.  No worries whatsoever.  Thank you very much.
Answer: Perhaps adding a script to the site that detects pasting of blocks of text over 150 (tweet-length) characters, and prompts an in-site pop-up with "Is this copied from an article?", reminding you to cite your source. For many people it may sadly just slip their mind, and this plagiarism may turn out to be negated by such a reminder.
Comment: No. I don't want to be badgered "is this plagiarism?" every time I answer a question.


Which Vedic verses describe Indra as Brahman?

Question: Which Vedic verses describe Indra as Brahman? Or as creator of universe or as source of universe or as someone who pervades whole universe?
Comment: It is not difficult to find such verses, however it is required to know how to properly interpret such verses, and that we learn in Vedanta. Just because some verse may seem to depict Indra as the Supreme or Brahman, it still doesn't necessarily mean that Indra is Brahman. That's why Vedanta is absolutely necessary to acquire proper knowledge of the verses we read in the scriptures.
Answer: Indra is called as the Lord of the Universe, the all pervader and the Supreme Lord in many Vedic verses. Here are some examples from RigVeda:

रूपं-रूपं परतिरूपो बभूव तदस्य रूपं परतिचक्षणाय |
  इन्द्रो मायाभिः पुरुरूप ईयते युक्ता हयस्य हरयःशता दश || (RigVeda 6.47.18)
  In every figure he hath been the mode: this is his only form for us to look on. Indra assumes many form by his Maya, for his Bay Steeds are yoked, ten times a hundred.

  यो विश्वस्य जगतः पराणतस पतिर्यो बरह्मणे परथमो गा अविन्दत |
  इन्द्रो यो दस्यून्रधरानवातिरन म... || (RigVeda 1.101.5)
He who is Lord of all the world that moves and breathes, who for the Brahman first before all found the Cows; Indra who cast the Dasyus down beneath his feet,—him girt by Maruts we invoke to be our Friend.

Let us praise him who made these worlds and creatures, all things that after him sprang into being. May we win Mitra with our songs, and Indra, and. wait upon our Lord with adoration. (RigVeda 8.85.6)

  Carrying your power, bear your hymns of affirmation to Indra as the Truth, if in truth he exists. " There is no Indra, some say to you. Who has seen him? Why should we praise him. " I am here, O singer, perceive me here. I transcend all Beings by my greatness, the directions of truth increase me, as the one who breaks things open, I break open the worlds." (Rig Veda 8.89.3-4)

Indra extends beyond heaven and earth. Half of him is equal to both the worlds. That is the truth Indra there is no other God or mortal greater than you. You are the king of the creatures of the world. You generated together the Sun, heaven and the Dawn. –(Rig Veda 6.30.1,4,5.)

Similarly, in the Taittariya Aranyaka of Krishna YajurVeda (in the part of MahaNarayaniya) it is stated:

VIII-1: The Supreme Being, Indra, who is the most excellent Pranava taught in the Vedas, who ensouls the entire universe, who leads the collection of Vedic utterances in Gayatri and other metres standing in their beginning, who is capable of being attained by the worshippers and who is the first in the causal link, taught the contemplative sages the sacred wisdom of the Upanishad, Himself being the subject-matter
  of them, in order to strengthen them with the power of knowledge. I salute the gods for removing the obstacles in my path to illumination. For the same I also reverence the Manes. The triple regions of Bhuh, Bhuvah and Suvah and the entire Veda are comprised in Om.

Similarly in the Kaushitki Aranyaka of RigVeda (where there is Kaushitki Brahmana Upanishad) it is told:

To him then Indra said: A superior verily chooses not for an inferior. Do you yourself choose. 'No boon verily then is it to me' said Pratardana. But Indra did not depart from
  the truth, for Indra is truth. To him then Indra said: 'Understand me only. This indeed I deem most beneficent to man, namely that one should understand me. I slew the three-headed Tvastir; I delivered the Arunmukhas, the ascetics, to the wolves. Transgressing many compacts I killed the people of Prahlada in the sky, the Paulomas in the
  atmosphere, the Kalakanjas on the earth. Of me, such as I was then, not a single hair was injured. So he knows me thus – by no deed whatever of his is his world injured,
  not by stealing, not by killing an embryo, not by the murder of his mother, not by the murder of his father. If he has done any evil, the dark colour departs not from his face.

  III-2. Then he (Indra) said: I am the Spirit of the vital breath, the intelligent Self. As such, worship me as life, as immortality. Life is the vital breath: the vital breath is life. For as long as the vital breath remains in the body so long is there life. For indeed with the vital breath one obtains immortality in this world; with intelligence, true conception. So he who worships me as life, as immortality, reaches the full term of life in this world; he obtains immortality and indestructibility in the heavenly world.

As a sidenote regarding the interpretation of such verses in the Vedanta, it is discussed in Brahma Sutras as;

Topic-11: Pratardana
     28. Prana is Brahman, because it is comprehended thus.
     29. If it be argued that Prana is not Brahman, since the instruction is about the speaker's own self, (then we say, no), for here is an abundance of reference to the inmost Self.
     30. But the instruction proceeds from a seer's vision agreeing with scriptures, as in the case of Vamadeva.
     31. If it be argued that Brahman is not spoken of here on account of the indications of the individual soul and the chief vital force, then that cannot be so, since this will lead to a threefold meditation. (Besides, Prana) is accepted (elsewhere) as meaning Brahman (because of the presence of Brahman's characteristics), (and these are) in evidence here.

The passage being discussed in the Brahma Sutra above is the same passage of Kaushitki Brahmana Upanishad which says Indra is Brahman. Here is commentary of Adi Shankaracharya on that part:

The individual divine Self called Indra perceiving by means of rishi-like intuition 1--the existence of which is vouched for by Scripture--its own Self to be identical with the supreme Self, instructs Pratardana (about the highest Self) by means of the words 'Know me only.'

  By intuition of the same kind the rishi Vâmadeva reached the knowledge expressed in the words, 'I was Manu and Sûrya;' in accordance with the passage, 'Whatever deva was awakened (so as to know Brahman) he indeed became that' (Bri. Up. I, 4, 10). The assertion made above (in the pûrvapaksha of the preceding Sûtra) that Indra after saying, 'Know me only,' glorifies himself by enumerating the slaying of Tvashtri's son and other deeds of strength, we refute as follows. The death of Tvashtri's son and similar deeds are referred to, not to the end of glorifying Indra as the object of knowledge--in which case the sense of the passage would be, 'Because I accomplished such and such deeds, therefore know me'--but to the end of glorifying the cognition of the highest Self. For this reason the text, after having referred to the slaying of Tvashtri's son and the like, goes on in the clause next following to exalt knowledge, 'And not one hair of me is harmed there. He who knows me thus by no deed of his is his life harmed.'--(But how does this passage convey praise of knowledge?)--Because, we reply, its meaning is as follows: 'Although I do such cruel deeds, yet not even a hair of mine is harmed because I am one with Brahman; therefore the life of any other person also who knows me thus is not harmed by any deed of his.' And the object of the knowledge (praised by Indra) is nothing else but Brahman which is set forth in a subsequent passage, 'I am prâna, the intelligent Self.' Therefore the entire chapter refers to Brahman.

Ramanujacharya commentary on the same:

As the Rishi Vâmadeva perceiving that Brahman is the inner Self of all, that all things constitute its body, and that the meaning of words denoting a body extends up to the principle embodied, denotes with the word 'I' the highest Brahman to which he himself stands in the relation of a body, and then predicates of this 'I' Manu Sûrya and other beings--'Seeing this the Rishi. Vâmadeva understood, I am Manu, I am Sûrya' (Bri. Up. I, 4, 10). Similarly Prahlâda says, 'As the Infinite one abides within all, he constitutes my "I" also; all is from me, I am all, within me is all.' (Vi. Pu. I, 19, 85.) The next Sûtra states, in reply to an objection, the reason why, in the section under discussion, terms denoting the individual soul, and others denoting non-sentient things are applied to Brahman.

And Srikantha Shivacharya in his commentary states:

The Sutrakara quotes an example, "like Vamadeva."  Vamadeva saw that Paramesvara was none but his own Atma and exclaimed " I have become Manu and Surya." Just so is Indra's declaration.

  Or thus : When, by the contemplation of the harmonious nature of Brahman and Atman brought about by Vedantic knowledge, Vamadeva attained to the state of Brahman and was freed from all the imaginary limitations due to the identifying of himself with the human body and so on, and his mighty ego expanded so as to embrace the whole universe, he saw that he was present everywhere and accordingly spoke of himself as one with the whole univierse including Manu and Surya. So, it maybe concluded, it was in the case of Indra. In the passage " I am prana, the conscious Atman," Prana refers to Para-Brahman, in as much as He , blissful by nature, is the cause of all life, as said in the sruti " Prana is the
  conscious self, the Bliss, undecaying and immortal." Accordingly it is from the standpoint of Brahman that Indra taught " I am Brahman," " me do thou worship " So, too, Krishna taught to Arjuna, and so several others.
Comment: @Rishabh these are puranic stories. do not mix up vedas and puranas to avoid confusion. Indra is supreme vedic god.
Comment: @Aks You said "Paramatman is Brahma, Shiva, Hari and Indra". You told me 4 names. But we often use to call Trideva (Brahma, Vishnu, Mahesh). The Trideva are Brahma (Creator), Vishnu (Protector) and Shiva (Destroyer). As we all know Brahma is creator and Vishnu is Protector and Shiva is Destroyer, Then who is Indra? What's his role? If he is Brahman then what he is doing for Brahman? Is he creating (like Brahma) OR Protecting (Like Vishnu) OR Destroying (Like Shiva)? What he does for Brahman?
Comment: Is he the same Indra who is King of heaven? If yes, then He also have done many sins in his life and also get beaten up badly by many demons and he force to leave heaven many times. He didn't had enough power to protect heaven from demons. And as per my knowledge He is God of Rain and also God of senses (may b). So on what bases he is called as Brahman since He is not enough powerful to protect heaven from demons. If he can't even protect his heaven then how can he protect us? And He also have done many grave sins too. So Why he is Brahman?
Comment: @rishabh in puranas you will also find stories which show Brahma or Vishnu or Shiva in less flattering light. Hinduism functions neither like strict monotheism nor like strict polytheism. Henotheism may be better word. When praising particular diety, that diety is called supreme and others shown "inferior". Other times those all supreme deities are declared one. Narayana suktam of yajurveda says "Paramatman is Brahma, Shiva, Hari and Indra".
Comment: @Aks His role is like all other Devas (like Sun, Wind ect). Nothing special than that.
Comment: This Indra could be the avatar of Lord Vishnu yajna who was Indra in one of the manavantaras - https://en.m.wikipedia.org/wiki/Yajna_(avatar)
Comment: @tezz Final nail in the coffin! :)
Comment: WHAT??? OMG!!!
Comment: I have a feeling the translations are inaccurate.
Comment: I don't think there are inaccurate translations...  Which translation do you think inaccurate?.. @Surya Kanta
Comment: Idk...I just have a feeling. Since Sanskrit words have multiple meanings, maybe there can be various translations for the same verse.
Comment: I.think brahma sutra portion is not needed as the question is not related to it...
Comment: If Indra is the supreme being then what is Krishna?
Answer: Brahman means knowing all. Knowledge. Lord Indra is the param Brahman that knows everything. As I understand Vishnu Brahma and Shiva are force of existence, they are the parameters and platforms. Consider, they are The inherent program of a PC that you can't see, or experience directly. They are the software code. Indra is like Windows. Every other program runs in windows, without which you can't do anything. Rest of the Gods are like MS office, Photoshop, Coreldraw etc that are empowering in their right. But without Windows they can't do anything.
Krishna is supposedly how the essence of universe it's collectve consciousness takes up a form. I'm not sure why, maybe to elevate or guide humanity. Because Gods won't guide humans to their greatness or their cycles. That interest lies with Krishna.
Comment: Welcome To Hinduism SE! Your analogy of software program is good. But answers on this site  has to be provided with  citing  sources from authentic hindu scriptures  and sources like Puranas , Mahabharata etc. Its a rule of the site , otherwise its possible that the answer might get deleted or will get converted to comment.
Comment: Apparently Wikipedia can also be cited as a valid source as someone mentioned to me in a comment on a new user's answer when I said wiki should not be considered an authentic source.
Comment: BTW lovely analogy @Vajra