Subscript with matrix generated by assign()

Question

I assigned a matrix to a name which varies with j:

j <- 2L
assign(paste0("pca", j,".FAVAR_fcst", sep=""), matrix(ncol=24, nrow=12))

This works very neat. Then I try to access a column of that matrix

paste0("pca", j,".FAVAR_fcst", sep="")[,2]

and get the following error:

Error in paste0("pca", j, ".FAVAR_fcst", sep = "")[, 2] : incorrect number of dimensions

I've tried several variations and combinations with cat(), print() and capture.output(), but nothing seems to work. I'm not sure what I have to search exactly for and couldn't find a solution. Can you help me?

what about `get(paste0("pca", j,".FAVAR_fcst", sep=""))[,2]` — Colonel Beauvel, Nov 27 '15 at 09:00
How about to read the help page of `assign`, particularly the last part of the example? — , Nov 27 '15 at 09:01

score 1 · Accepted Answer · answered Nov 27 '15 at 09:00

1

You can use get :

get(paste0("pca", j,".FAVAR_fcst", sep="")) # for the matrix

get(paste0("pca", j,".FAVAR_fcst", sep=""))[,2] # for the column
# [1] NA NA NA NA NA NA NA NA NA NA NA NA

An other solution would be to combine eval and as.symbol :

eval(as.symbol(paste0("pca", j,".FAVAR_fcst", sep="")))[,2]
# [1] NA NA NA NA NA NA NA NA NA NA NA NA

answered Nov 27 '15 at 09:00

etienne

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mostly, another solution would be to put matrixes in a list! – Colonel Beauvel Nov 27 '15 at 09:04

Subscript with matrix generated by assign()

1 Answers1