Hello all -
I have an example column in a dataFrame
id.name
123.45
123.45
123.45
123.45
234.56
234.56
234.56
234.56
234.56
234.56
234.56
345.67
345.67
345.67
456.78
456.78
456.78
456.78
456.78
456.78
456.78
456.78
456.78
...
[truncated]
And I'd like to create a second vector of sequential values (i.e., 1:N) for
each unique id.name value. In other words, I need
id.name x
123.45 1
123.45 2
123.45 3
123.45 4
234.56 1
234.56 2
234.56 3
234.56 4
234.56 5
234.56 6
234.56 7
345.67 1
345.67 2
345.67 3
456.78 1
456.78 2
456.78 3
456.78 4
456.78 5
456.78 6
456.78 7
456.78 8
456.78 9
The number of unique id.name values is different; for some values, nrow()
may be 42 and for others it may be 36, etc.
The only way I could think of to do this is with two nested for loops. I
tried it but because this data set is so large (nrow = 112,679 with 2,161
unique values of id.name), it took several hours to run.
Is there an easier way to create this vector? I'd appreciate your thoughts.
Thanks -
SR
Steven H. Ranney
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