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POConvert factor to time in R
 

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  1. POConvert factor to time in R
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    <p>I have a small problem which I cannot seem to figure out. I have searched several topics and websites to find a solution, and I have tried numerous different things but nothing seems to work..<br> I have a dataset with two columns, one for date and one for time:</p> <p>$ StartDate : Date, format: "2013-09-01" "2013-09-01" "2013-09-01" "2013-09-01" ...<br> $ StartTime : Factor w/ 43 levels "00:02:43","00:07:05",..:</p> <p>As you can see, I already converted the column "StartDate to "Date" and I would like to convert the column StartTime to "POSIXct".. I had a big dataset which I splitted, in this big dataset I had the variables date and time set right. I used the following loop to split the file:</p> <pre><code>for (Cow in unique(df$CowID)){ #loop through each level of CowID df &lt;- RawData[df$CowID == Cow,] #extract all rows where CowID equals Cow write.csv(df, paste("CowID_",Cow,".csv",sep = ""),row.names = F)} #write new dataframe to .csv </code></pre> <p>Should I have used an extra piece of code to keep the variables? After using this loop I got 68 different .csv files which I then separately read into R by using the next code:</p> <pre><code>C292 &lt;- read.csv(file = "C:\\...\\CowID_12292.csv", header = T, skip = 0, colClasses = c("StartDate" = "Date", "Date" = "Date", "StartTime" = "character", "Time" = "character")) </code></pre> <p>Ofcourse, now these variables for time are "chr". I have no clue how to convert this.. Can anyone help me? I tried <strong>as.POSIXct()</strong> but that did not seem to work, I only NA in the column..</p> <p>Thanks in advance!</p> <p>ADD > dput(head(C292))</p> <blockquote> <p>structure(list(CowID = c(12292L, 12292L, 12292L, 12292L, 12292L, 12292L), StartDate = structure(c(15949, 15949, 15949, 15949, 15949, 15949), class = "Date"), StartTime = c("02:16:16", "02:16:16", "02:16:16", "02:16:16", "02:16:16", "02:16:16")</p> </blockquote> <p>Do I really need to add the date into the column time? Or is there also a way to leave it out, but still keep the variable POSIXct? I would like to split the file by date and then plot the days on a timeline of 24hours. I do not know if this is even possible, I am quite a noob in R. However, it is a very clever program so I guess it is possible. Just have to figure out a way to do it!</p>
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    1. USJalalala
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    1. COCan you paste the output of `dput(head(C292))`?
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      1. USStephan Kolassa
    2. COI put it in! Can you help me?
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      1. USJalalala
    3. COActually, you put in the results of `head(C292)`, not of `dput(head(C392))`... the first tells us what you see on your screen, but not what data types R uses. `dput` allows us to have exactly the same data in our R sessions as you do, so we can actually help you. And I see that you already accepted an answer. So if you still need help, please paste the results of `dput(head(C292))`` and tell us what is still unclear.
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      1. USStephan Kolassa
 

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