Re: st: RE: Create graph directly from matrix?

[Nick Winter <nwinter@virginia.edu>]

Ah, interesting.

Looking within -_matplot-, it looks like the fundamental answer to my 
question might be "no", since that program creates temporary variables 
that it then plots.

But it uses an interesting construction that may help me go the 
variables route without using -svmat-:

gen x = Xy[_n,1] in 1/16

creates a new variable -x- from the first column of matrix Xy.  Pretty 
spiffy to use _n to tag the observation number/row number.

- Nick

Nick Cox wrote:
> Check out the undocumented command -_matplot-. 
>
> Nick 
> n.j.cox@durham.ac.uk 
>
> Nick Winter
>
> I'm wondering if there is a way to convert the values held into a matrix
>
> into a graph (ie, into a serset that serves as the basis for a graph) 
> directly, without first making the matrix into variables?
>
> Why I'm curious:
>
> I'm thinking about revising my -oprobpr- command, which plots predicted 
> probabilities after order l/probit models.  The new -margins- command 
> can fairly easily calculate what's required for the plotting, and those 
> results can be saved as a matrix, using -margins-'s -post- option.
>
> So I'd like to plot the estimates returned in e(b) against values in
> e(at).
>
> I can put this stuff all together in one matrix, eg:
>
> sysuse auto
> probit foreign mpg price weight
>
> margins, atmeans at(mpg=(12(2.9)41)) post
> mat b = e(b)
> mat X = e(at)
> mat Xy = X , b'
>
> Then I'd like to create, eg, a line plot of the final column (named y1) 
> against the first column (mpg).
>
> I can, of course, use -svmat-, graph the relevant variables, and drop 
> the variables.
>
> But I'd love a more elegant solution.
>
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--
--------------------------------------------------------------
Nicholas Winter                                 434.924.6994 t
Assistant Professor                             434.924.3359 f
Department of Politics                  nwinter@virginia.edu e
University of Virginia          faculty.virginia.edu/nwinter w
PO Box 400787, 100 Cabell Hall
Charlottesville, VA 22904

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