title: how to group character vectors in a data frame in r
body: <p>I have a dataframe that I am trying to group so I can do some basic stats on each group. However, since the column I am using to group is a character vector, I am not successful in my various attempts to get this done. Here is a sample</p>
  
  <pre><code>    Name Value rate
  1  SW115    25    3
  2  SW115    34    3
  3  SW115    25    3
  4  SW115    30    3
  5  SW115    36    3
  6  SW345    32    4
  7  SW345    43    4
  8  SW345    35    4
  9  SW345    24    4
  10 SW345    23    4
  11 SW445    32    5
  12 SW445    33    5
  13 SW445    24    5
  14 SW445    35    5
  15 SW445    25    5
  </code></pre>
  
  <p>As I said, I would like to group it by "name", and find the mean and cv of of "value" for each group. So, in my example, SW115 would be a group and SW345 would be another group, and I would like to know the mean, sd, and coefficient of variation of each group. I can do this manually by subsetting, but the original data I am working wits has over 5000 rows with about 57 possible groups and it would take me hours to go through each group manually. I know there has to be a way to get it done with a few line of codes so that it pits out the summary for each group all that once.</p>
  
  <p>I tried converting the column "name" to a numbers (so that each group has a number), but I just couldn't get it done as well.</p>
  
  <p>Any suggestions would be greatly appreciated</p>