st: Unnecessary Labels for Graphs

[Matthew Mulligan <matt88is@gmail.com>]

Dear Statalist

I have to make a series of line graphs that I am hoping to use in a
loop. Howver, for certains variables of varlist prov_cov_`x' does not
equal one, and therefore the line does not show up on the graph.  This
was intentional as I am hoping only graph certain lines for certain
variables. The problem is that there is still a label for that line,
taken from the previous existing line.  Without completely removing
the legend, is there a way of forcing the label for the line that does
not exist to not show up. I would appreciate your help.  Code below:

foreach x of local varlist {
	graph twoway ///
		( line cov_`x' date if prov==2 & prov_cov_`x'==1, lwidth(thick)
yvarlabel("Prov1")) ///
		( line cov_`x' date if prov==5 & prov_cov_`x'==1, lwidth(thick)
yvarlabel("Prov2")) ///
		( line cov_`x' date if prov==8 & prov_cov_`x'==1, lwidth(thick)
yvarlabel("Prov3")) ///
		( line cov_`x' date if prov==9 & prov_cov_`x'==1, lwidth(thick)
yvarlabel("Prov4")) ///
		( line cov_`x' date if prov==11 & prov_cov_`x'==1, lwidth(thick)
yvarlabel("Prov5"))
}


Matt
Research Assistant
World Bank
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