st: marksample

["Ashim Kapoor" <ashimkapoor@gmail.com>]

Hello everyone,

I am trying to learn MATA. I have a query. What is marksample ? Does
it  return a matrix  with 0's in place of variables which are NOT
marked. Is it ONLY used after syntax ?

I did not find the help very useful. Can someone please shed some
light on this ?

Thank you,
Ashim.
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