r - apply calculation on multiple columns of each element in a list -

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i have list consist of 23 elements 69 rows , 13 columns each. , need apply calculation on multiple columns each element of list.

as simple example, list looks this: 

>list >$`1`  >             b     c  >1    2.1    1.4    3.4  >2    4.4    2.6    5.5  >3    2.6    0.4    3.0  ...   >$`2`  >            b        c  >70    5.1    4.9    5.1  >71    4.4    7.6    8.5  >72    2.8    3.5    6.8  ...

what wish z = (a-b) / c each element ($1,$2..., $23)

i tried following code:

for( in 1:23) {
z = (list[[i]]$a - list[[i]]$b) / list[[i]]$c }

which gave me 49 values, rather 1566 values.

anyone have idea wrong code , able correct it? thank much!

you can function lapply(). here example assuming in data frame columns have same name.

ll<-list(data.frame(a=1:3,b=4:6,c=7:9),          data.frame(a=1:3,b=6:4,c=7:9),          data.frame(a=1:3,b=4:6,c=9:7))  lapply(ll, with, (a-b)/c)

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