st: Optional arguments in Mata

["Le Wang" <statauser@gmail.com>]

Hi there,

Thanks in advance for your time.

I am trying to program a Mata function with optional arguments. For
example,  I want to: (1) read the data y and x (2) create a matrix
equals x and J(rows(x),1,1) (constant) (3) create a matrix x'*y

void myfunction(string scalar depvar, | string scalar varlist)
{
      st_view(y=.,.,depvar,.)
      st_view(x=.,.,varlist,.)

      x=x,J(rows(x),1,1)

      x'*y
}

The program will work fine if i specify the varlist
        myfunction("y","x")

However, it won't work if I don't specify the varlist because
"st_view(x=.,.,varlist,.)" requires an argument. How should I solve
this problem?

Thanks.

Le
-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~
Le Wang, Ph.D.
Minnesota Population Center
University of Minnesota
(o) 612-624-5818
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