using nrow to identify one row

nrow is for number of rows in matrix/data.frame, here you can use:

NROW(temp[1,])
length(temp[1,])

But if you want the index of row try this:

unique(row(temp)[1,])
Hi fellow R-users,

 I have run into a problem when trying to identify the number of rows in a matrix. Say we have an arbitrary 5 by 5 matrix called temp:

 temp <- matrix(norm(25), nrow=5)

 The problem is that nrow(temp[1,]) returns NULL. I would like it to return 1 because in my larger program I am indexing the rows of large matrices according to another variable and I need to test when the resulting matrices have 0, 1 or more rows.

 Thanks in advance for any assistance.

 Best regards,
 Gregory Gentlemen

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using nrow to identify one row

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