Divide a matrix

[Marc Audrna]

Hello,

How can I devide a matrix by an other matrix (not a division by scalar) ?
By the way, I tried : mat xxx = zz * 1/yy , without résult...

Thank you for your answer
Marc

[Nick Cox]

You can do it by pushing into Mata, doing the work there, and pulling the results out of Mata:

. matrix X = (4, 8 \ 16, 32)

. matrix Y = (2, 2 \ 4,4)

. mata: st_matrix("XoverY", st_matrix("X") :/ st_matrix("Y"))

. matrix li XoverY

symmetric XoverY[2,2]
    c1  c2
r1   2
r2   4   8

There is also a clunky 1999 vintage program matewd

STB-50 dm69 . . . . . . . . . . . . . . . . . . Further new matrix commands
(help matdelrc, matewm, matmad, matpow if installed) . . . N. J. Cox
7/99 pp.5--9; STB Reprints Vol 9, pp.29--34
collection of new matrix commands providing additional matrix
checking, management, element-wise operators, maximum absolute
difference, and power

You're better off learning some Mata!

[Marc Audrna]

Thank you, I'm Mata Happy !

[David Rolls]

Hi,

I would like to sum two variables of my sample and then divide these two results together. Finally I would like to export both sum and the result of the division.

I found a way for both sum but I do not find how to proceed for the division. I have the following code :

Code:
.estpost tabstat VARIABLE1 if year == 2008, statistics(sum)
.esttab, wide nonumber cell("sum(label(Total Variable1 in 2008))")
.mat II = e(sum)'
.estpost tabstat VARIABLE2 if year == 2008, statistics(sum)
.esttab, wide nonumber cell("sum(label(Total Variable2 in 2008))")
.mat JJ = e(sum)'
.putexcel set "name.xlsx", replace
.putexcel A3 = "2008"
.putexcel B3 = matrix(II)
.putexcel C3 = matrix(JJ)

Thank you in advance.

David