topic Graph a mathematical function in SAS Procedures

Graph a mathematical function

Daniel — Tue, 09 Feb 2016 16:34:43 GMT

Dear All,

Aside from simulating data in a data step and then use a procedure such as PLOT, GPLOT, SGPLOT, etc. is there any way to graph a mathematical function (say y = x**2) by simply inputting the function and requesting a graph?

For me, the go-to method was the above, i.e. simulate the data first and then plot it, but I thought there might be some function out there (or something in either EG or IML Studio perhaps) that would do the trick.

Thank you for your input

Re: Graph a mathematical function

PGStats — Tue, 09 Feb 2016 18:25:29 GMT

Took me about 30 seconds to write

data function;
do x = -1 to 4 by 0.05;
    y = x**2;
    output;
    end;
run;

proc sgplot data=function;
series x=x y=y;
run;

and get a decent basic graph. SAS software (GTL, SG, SAS/GRAPH, even JMP) doesn't graph user-specified functions, only data.

Re: Graph a mathematical function

Rick_SAS — Wed, 10 Feb 2016 13:39:14 GMT

@PGStats shows the usual method. Since you mentioned IML, I'm thinking that perhaps your function is defined by a function module? If so, you can use a similar approach from inside SAS/IML:

proc iml;
start MyFunc(x);
   return( x##2 );
finish;

t = do(-2, 2, 0.1);
call series(t, MyFunc(t));

From inside SAS/IML Studio you can get an interactive plot by using

LinePlot.Create("function plot", t, MyFunc(t));

Re: Graph a mathematical function

Jeff_Perkinson — Fri, 12 Feb 2016 21:35:47 GMT

Just to clear up a misconception, JMP will plot functions.

See the Formula Element in Graph Builder or for more flexibility the Y Function() in graphic scripting.

For functions in more than two dimensions the various Profilers in JMP offer the ultimate flexibility.

-Jeff