Dear All,
wonder if you have thoughts on the following:

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let us say we have:
df<-data.frame(a=c(1,2,3,4,5,1,2,3,4,5,6,7,8),b=c(0,1,2,3,4,0,1,2,3,4,5,6,7))
I would like to rewrite values in column name "a" based on values in column
name "b", where based on a certain value of column "b" the next value of column
'a' is prompted, in other words would like to have this as a result:
df<-data.frame(a=c(1,1,1,1,1,2,2,2,2,2,2,2,2),b=c(0,1,2,3,4,0,1,2,3,4,5,6,7))
where at the value of 0 in column 'b' the number in column a changes from 1 to
2. From the first zero value of column 'b' and until the next zero in column
'b' the numbers would not change in 'a', ie: they are all 1 in my example...
then from 2 it would change to 3 again as 'b' will have zero again in a row,
and so on.. Would be grateful for a solution that would allow me to set the
values (from 'b') that determine how the values get established in 'a' (ie:
lets say instead of 0 I would want 3 being the value where 1 changes to 2 in
'a') and that would be flexible to take into account that the number of rows
and the number of time 0 shows up in a row in column 'b' may vary...
much appreciate your thoughts..
Andras
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