[R] How to split two levels several times?

[Rui Barradas]

Hello,

Try the following.


idx <- cumsum(c(TRUE, diff(dat$electrode == "electrode1") > 0))
split(dat, idx)


Hope this helps,

Rui Barradas

Em 22-07-2013 15:09, dennis1991 at gmx.net escreveu:
> Hi,
>
> I have a small problem with the function split() and would appreciate your help.
>
> I have a table called “XXX” with 2 columns and 49 rows. The 49 rows belong to 8 different levels (electrode1, ...,electrode8). I want to split the table always at the row where “electrode1” starts again so that I can export 7  individual dataframes (numbered “dataframe1” to ”dataframe7”) which contain always electrode1 as first level (always three rows) with the varying number of rows for electrodes2-8 below.
> I tried the split function with various setups:
>
> t <- as.factor(XXX$electrode)
>
> dataframeX <- split(XXX, f=(levels=t))
>
> But this doesn’t work. Could you please help. Thank you! Dennis
>
>
> This is the table "XXX"
>
> electrode	length
>
> electrode1	5.7
> electrode1	6.3
> electrode1	6.2
> electrode2	11.4
> electrode2	9.7
> electrode1	5.7
> electrode1	6.3
> electrode1	6.2
> electrode3	14.2
> electrode3	14.8
> electrode3	12.6
> electrode1	5.7
> electrode1	6.3
> electrode1	6.2
> electrode4	17.0
> electrode4	16.3
> electrode4	17.8
> electrode4	18.3
> electrode4	16.9
> electrode4	18.5
> electrode1	....
> ....		....
> electrode5	....
> ....		....
> electrode1	....
> electrode6	....
> electrode1	....
> electrode7	....
> electrode1	....
> electrode8	....
>
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