palette:transparency-of
palette:transparency-of color
Reports a value in the range 0 to 100 representing the percent transparency of the given NL, RGB or RGBA color. The percent transparency of an NL or RGB color is 0.
Example:
show palette:transparency-of [100 100 100 100] ;; 60.7843137254902
show palette:transparency-of red ;; 0
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