# st: RE: percentage for each month plotted vs. month

 From "Nick Cox" <[email protected]> To <[email protected]> Subject st: RE: percentage for each month plotted vs. month Date Mon, 2 May 2005 15:37:52 +0100

```I assume variables

date: Stata daily date
x: as defined below

You can get months by

gen month = month(date)

The percent of drug use would then be

egen adult_x = mean(100 * (2 - x)) if adult == 1, by(month)

egen child_x = mean(100 * (2 - x)) if adult == 2, by(month)

The graph would be

line *_x month

To cycle over many months,

foreach v of var x y z a b c d e f {
egen adult_`v' = mean(100 * (2 - `v')) if adult == 1, by(month)
egen child_`v = mean(100 * (2 - `v')) if adult == 2, by(month)
line *_`v' month, saving(`v')
more
}

Note how binary coding 1 for use, 0 for no use, would lead
to cleaner formulae.

Nick
[email protected]

[email protected]

> I have the following survey data of 1000 patients collected over 15
> months:
>
> Each observation contains the following variables:
> X:  "1" for using drug x and "2" for not using drug x
> DATE: Day and month patient was enrolled in study (variable
> DATE as day
> month year)
> Adult: "1" yes "2" no
>
> I would like to plot the percentage of patients who were
> using drug x in a
> given month  vs. month & year. So the axes would be Y: "percent of
> patients using drug x in given month" and X axis: "month & year of
> enrollment"
>
> I cannot seem to figure out an easy way to do this.  It seems
> that I have
> to generate many variables to get a simple percentage of
> patients who were
> using drug x for that particular month and then to plot it.
>
> Also, I would like to get more sophisticated as well: the
> same graph as
> above but have two lines on one graph; one line would
> represent the data
> for children and the other for adults.
>
> Also, I'd like to generate many graphs using the do editor
> (same as above
> for other drugs).  When I try using the do editor this, I get
> one graph
> and then the next is shown and I get to save only the last.
> Is there a
> way I could run several graphs using the do editor and then
> save them all
> so that I could view them leisurely?
>
> I have a copy of Mitchell's excellent book on STATA graphics
> and still
> can't figure this out!

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