title: Convert chr to time format using chorn
body: <p>I am trying to transform my date dataset from chr to time format.</p>
  <p>Here is my code :</p>
  <pre><code>time&lt;-f1%&gt;%
    mutate(`ymd_hms(Timestamp)`=strftime(f1$`ymd_hms(Timestamp)`, tz=&quot;GMT&quot;, format = &quot;%H:%M:%S&quot;))%&gt;%
    transform(as.numeric(f1$SpotPrice))
    chron(times=f1$`ymd_hms(Timestamp)`)
  </code></pre>
  <p>its showing error:</p>
  <pre><code>Error in chron(., times = f1$`ymd_hms(Timestamp)`) : 
    . and f1$`ymd_hms(Timestamp)` must have equal lengths
  </code></pre>
  <p>if i comment it</p>
  <pre><code>time&lt;-f1%&gt;%
    mutate(`ymd_hms(Timestamp)`=strftime(f1$`ymd_hms(Timestamp)`, tz=&quot;GMT&quot;, format = &quot;%H:%M:%S&quot;))%&gt;%
    transform(as.numeric(f1$SpotPrice))
  #chron(times=f1$`ymd_hms(Timestamp)`)
  </code></pre>
  <p>output is</p>
  <pre><code>'data.frame':   10078 obs. of  4 variables:
   $ InstanceType      : chr  &quot;  a1.2xlarge&quot; &quot;  a1.2xlarge&quot; &quot;  a1.2xlarge&quot; &quot;  a1.4xlarge&quot; ...
   $ ProductDescription: chr  &quot;  Linux/UNIX&quot; &quot;  Red Hat Enterprise Linux&quot; &quot;  SUSE Linux&quot; &quot;  Linux/UNIX&quot; ...
   $ SpotPrice         : num  0.0671 0.1971 0.2171 0.1343 0.2643 ...
   $ ymd_hms(Timestamp): chr  &quot;06:17:23&quot; &quot;06:17:23&quot; &quot;06:17:23&quot; &quot;12:15:54&quot; ...
  </code></pre>
  <p>Also but i use this commend as a single variable as follows:</p>
  <pre><code>f2&lt;-chron(times=DfUse$`ymd_hms(Timestamp)`)
  </code></pre>
  <p>it works and shows the output</p>
  <pre><code> 'times' num [1:10078] 06:17:23 06:17:23 06:17:23 12:15:54 12:15:54 ...
   - attr(*, &quot;format&quot;)= chr &quot;h:m:s&quot;`
  
  </code></pre>
  <p>but i want to pipe it with my whole dataset not to use it alone as a single variable.</p>
  <p>Thanks in advance.</p>