Transparency in graphs not working with scheme-specific colors

[Jan Kabatek]

Hello everyone, I'm trying to produce a histogram in Stata 17 with the following attributes:

1. using a custom scheme,
2. explicitly declaring the bar color to be one of the default colors defined within the given scheme file
3. adjusting the transparency of this bar color.

According to my google search, this can be done using the following command:

hist mpg, fcolor("scheme p1%50") scheme(economist)

and it works well as long as the scheme’s default colors (as defined in the corresponding scheme file) are sourced from the standard Stata color class:

color p1 maroon

But, it does not work when the scheme’s default colors are defined as RGB:

color p1 "230 92 92"

In the latter case, adjusting transparency fails. See the example below:

net install schemepack, from("https://raw.githubusercontent.com/asjadnaqvi/Stata-schemes/main/schemes/") replace
 
sysuse auto, clear
 
hist mpg, fcolor("230 92 92%50") scheme(neon)    name(g1,replace) title("with RGB color")
hist mpg, fcolor("26 71 111%50") scheme(s2color) name(g2,replace) title("with RGB color")
 
hist mpg, fcolor("scheme p1%50") scheme(neon)    name(g3,replace) title("with scheme pX color")
hist mpg, fcolor("scheme p1%50") scheme(s2color) name(g4,replace) title("with scheme pX color")
 
graph combine g1 g2 g3 g4

The bottom-left chart is the one with failed transparency. I suspect the problem is that the color p1 in the corresponding scheme file is defined as an RGB in parentheses, and these parentheses mess up the fcolor("scheme p1%50") option.

Would you happen to know whether there is a way to make the command below work properly?

hist mpg, fcolor("scheme p1%50") scheme(neon)

Thank you,

Jan

[Jan Kabatek]

solved:

hist mpg, fcolor("`.__SCHEME.color.p1'%50") scheme(neon)

[FernandoRios]

alternative:

histogram price, scheme(neon) color(%50) pstyle(p2)

[Jan Kabatek]

Very elegant, thanks!