for
for <block number> operations....; for TAG <string> operations.....
Variants:
for TAG <string> c1 c2 0.01*c2
Searches hashtag TAG and <string> in that line. For each DATA block whose TAG contains the string it applies the column operations .
for ALL sort
(character * can be used instead of "ALL" or "all")
for * sort
applies sort to all data blocks (NOTE the difference if you try to use only "sort")
for 3 c1 c2 sqrt(1.34)
applies the column operations to data set block 3 alone