title: How to create one date/time column in a dataframe in R?
body: <p>The data frame I am working with:</p>
  
  <pre><code>head(ossub3)
  
  date---------|os5 | os6 |  os7| os8 | _ _Year| Month|Day|Hour|Minutes 
  11/15/2015|10.06|16.94|10.63|12.94  |2015|11|15| 12|08 
  </code></pre>
  
  <p>I have all of the time units separated into columns. I would like one datetime column in R. I have tried the solutions on <a href="https://stackoverflow.com/questions/11609252/r-tick-data-merging-date-and-time-into-a-single-object">R tick data : merging date and time into a single object</a> and on <a href="https://stackoverflow.com/questions/15982722/strip-the-date-and-keep-the-time">Strip the date and keep the time</a> because when I try to </p>
  
  <pre><code>#Combine Date 
  
  ossub3$Date&lt;-as.POSIXlt(paste(ossub3$Year, ossub3$Month, ossub3$Day, sep="-"), 
      tz = "US/Central", format = "%Y-%m-%d")
  
  #Create new column called Time which concatenates Hour, Minute as a POSIXlt 
  
  ossub3$sec=rep(00,nrow(ossub3))
  ossub3$Time&lt;-as.POSIXlt(paste(ossub3$Hour, ossub3$Minute,ossub3$sec, sep=":"), 
      tz = "US/Central", format = "%H:%M")
  </code></pre>
  
  <p>I get today's date in my time so I can't combine it with the date.  What is going on here?  </p>