st: Using a loop to calculate vector differences

["Heidi M Pitts" <hpitts@unm.edu>]

Hi listers,
Can anyone help fix my code for the following issue:

I have two vectors:
M=[0, 0, 0, 0, 0, 0, 0, .1, .4, .4, .1]
F=[0, 0, 0, 0, 0, .05, .3, .6, .05, 0, 0]
so n=11 obs for each vector.

I?m trying to calculate the vector difference between each 
element `i? in M and the whole vector F.    So the first 
vector of differences would be [M1=0 minus 
0,0,0,0,0,.05,.3,.6,.05,0,0].  Then I would calculate a 
second set of differences, M2=0 - same F vector, and stack 
it under the diff vector.

I have written a simple loop to calculate each difference. 
But the error message I get is: ?x_male1 not found?. 
Seems that my code is not recognizing that I want the 
first element of M to subtract each element of F and 
populate the vector ?diff?.  Can anyone help?  Seems that 
the first issue is that ?x_male1? is not equal to 0, the 
first element in the vector.


/************  program to calculate difference of 
distributions***************/
set matsize 100

mkmat x_male
mkmat y_female
mkmat y_fem_inv

set obs 11
gen n=_n
gen diff=.
mkmat diff
forvalues i=1(1)11 {
	gen y=x_male`i'-y_female
	replace diff=y if `i'< n

}

/*****************************************/



Thanks for any help!


Sincerely,
Heidi M. Pitts
Graduate Student
Department of Economics
University of New Mexico

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