topic Re: interpol in Graphics Programming

interpol

miguelito — Fri, 06 Jan 2017 15:21:43 GMT

Hello,

I am producing gplots using the proc gplot procedure that is available in SAS/GRAPH and I am wondering where I can get the whole list of Interpol methods (e.g., join, steplj, etc.) and where I can get an accurate description of the method called 'steplj'? I looked at the documentation and I was not able to find it anywhere. Is there an new alternative for steplj in the new STAT/GRAHP?

Re: interpol

Reeza — Fri, 06 Jan 2017 15:50:08 GMT

INTERPOL is under the SYMBOL statement and the options are listed under there.

http://support.sas.com/documentation/cdl/en/graphref/69717/HTML/default/viewer.htm#n0c0j84n1e2jz9n1bhkn41o3v0d6.htm

In your case, STEPLJ means plotted with a step function, displays teh data point on the left of the step and produces steps with joined lines.

INTERPOL=STEP<placement><J><S>

specifies that the data are plotted with a step function. By default, the data point is on the left of the step, the steps are not joined with a vertical line, and the data are not sorted before processing.

Specify one of these values for placement:

L

displays the data point on the left of the step.

R

displays the data point on the right of the step.

C

displays the data point in the center of the step.

In addition, specify one or both of these:

J

produces steps joined with a vertical line.

S

sorts unordered data by the independent variable before plotting.

Re: interpol

DanH_sas — Fri, 06 Jan 2017 15:52:46 GMT

The list of interpolations can be found here: http://support.sas.com/documentation/cdl/en/graphref/69717/HTML/default/viewer.htm#n0c0j84n1e2jz9n1bhkn41o3v0d6.htm

As for "STEPLJ", that is a joined (J) step plot where the data points justified to the left (L) side fo the step. The is actually the default way that STEP plots are rendered in ODS graphics.

proc sort data=sashelp.class out=class; by weight; run;
proc sgplot data=class (obs=4);
step x=weight y=height;
scatter x=weight y=height;
run;

You can use the JUSTIFY option to change the of the data value along the step.

Hope this helps!

Dan