title: I am unable to change a column into Date format in R
body: <p><img src="https://i.stack.imgur.com/LtU6g.png" alt="This is how my data looks"></p>
  
  <p>And this is the string of my dataframe.</p>
  
  <pre><code>'data.frame':   10652 obs. of  4 variables:
   $ Date: chr  "06-15-2017" "06-15-2017" "06-15-2017" "06-15-2017" ...
   $ Time: Factor w/ 951 levels "00:00:01","00:00:02",..: 396 398 400 402 404 406 407 409 411 413 ...
   $ CPU : num  2.4 2.4 2.3 2.3 2.2 2.2 2.1 2.1 2.1 2.1 ...
   $ MEM : num  2.5 2.5 2.5 2.6 2.6 2.6 2.6 2.7 2.9 2.9 ...
  </code></pre>
  
  <p>I want to make R read the date and time column in Date and Time format. </p>
  
  <p>I have tried:</p>
  
  <ol>
  <li><p><code>DateData$Date_Time = within(DateData, { timestamp=format(as.POSIXct(paste(DateData$Date, DateData$Time)), "%d/%m/%Y %H:%M:%S") })</code></p></li>
  <li><p>I have tried this after merging the date and time column-<br>
  <code>DateData$Date_Time = as.chron(DateData$Date_Time, "%d/%m/%Y %H:%M:%S")</code></p></li>
  <li><p><code>DateData = within(DateData, { timestamp=strptime(paste((DateData$Date, DateData$Time), "%Y/%m/%d%H:%M:%S") })</code></p></li>
  <li><p>And this: <code>DateData$DateTime = strptime(DateData$DateTime,"%m-%d-%Y %H:%M:%S")</code></p></li>
  </ol>
  
  <p>Nothing seems to work for me.</p>