PROC GPLOTS
You say plots earlier. The plots have a few new features to examine. These are the
symbol, interpol, and line.
symbol is used to define points on the plot with a certain symbol. These can vary.
interpol or (I) is used to join the symbols together. There are a few options available.
These are join, spline, rl or clm.
interpol=join means that the points are joined together.
interpol=spline makes a smooth line through the points.
interpol=rl is used for regression analysis. This finds the best fit for a line
through the plot. The rl stands for regression line.
interpol=clm is used to define confidence limits for a mean predicted value.
These are usually set to a 95 percent limit.
line or (L) allows you to specify what type of line you want to use. There are 46
different line styles. line=1 would give you a solid line. You can add width to a line to
make it thicker.
Height can also be used in a SYMBOL statement. You can emphasize the symbol if you
want.
This first plot is a line chart. It displays the same information as the hbar chart of
Comparison of Undergraduate Enrollments. There are three lines with a symbol that represents
the total number of students for each year. One of the reasons that this particular plot is shown
here is that there is more than one way to display the same information. It would depend on
your audience or what you think gets your point across the best. You would have to decide on
which one you like the best.
data major3;
set major;
symbol1 v=star h=2 i=spline l=1 c=red;
symbol2 v=circle h=2 i=spline l=10 c=green;
symbol3 v=diamond h=2 i=spline l=15 c=blue;
proc gplot;
where college = 'AS' or college = 'BU' or college = 'EN';
plot total* year=college;
format college $univ.;
title 'Plot of College Enrollments by Year at OSU';
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