search for: mrunoff_207104

...ay by which I can extract each of the third dimension of these grids (1:12) in turn, along with the first and second dimensions, to create new objects in the following style: #2071 mrunoff_207101 <- mrunoff_5221[,,1] mrunoff_207102 <- mrunoff_5221[,,2] mrunoff_207103 <- mrunoff_5221[,,3] mrunoff_207104 <- mrunoff_5221[,,4] mrunoff_207105 <- mrunoff_5221[,,5]?? ...(etc. - up to [,,12]) #2072 mrunoff_207201 <- mrunoff_5222[,,1] mrunoff_207202 <- mrunoff_5222[,,2] mrunoff_207203 <- mrunoff_5222[,,3] mrunoff_207204 <- mrunoff_5222[,,4] mrunoff_207205 <- mrunoff_5222[,,5]? ...(et...

...the following error: "Error in Ops.data.frame(mrunoff_207101[3], mrunoff_207102[3]) : ? + only defined for equally-sized data frames". Here is what I'm attempting to do: > arunoff_2071 <- cbind(mrunoff_207101[1:2], (mrunoff_207101[3] + mrunoff_207102[3] + mrunoff_207103[3] + mrunoff_207104[3] + mrunoff_207105[3] + mrunoff_207106[3] + mrunoff_207107[3] + mrunoff_207108[3] + mrunoff_207109[3])) Is there an easy way of summing based on congruent values in columns 1 and 2? The only way I can think of would be to use merge, but this would involve doing this for every pair of data frames...