st: matrix subscripting using loop

[Thomas <tpt21@cam.ac.uk>]

I would like to turn a 1 X 49 matrix into a 7 X 7 matrix using a loop.

I tried the following:

mat evi = J(7,7,0)

            forvalues r = 1(1)7{
                forvalues i = 1(7)43{
                    forvalues j = 7(7)49{

                        matrix evi[`r',1] = evimat[1,`i'..`j']
            }
            }
            }

it does not seem to work because it first loops over the first set of 
forvalues, then the second, etc.

But what I need is for it to loop over all three forvalue statements "at 
the same time". Any idea how to do this?

Then there might a an altogether different way of doing this...

Many thanks,

Thomas
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