get alpha (color) value of a line
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i need to copy a line to another plot, the copied line have alpha color value (Transperency / grey visibility) :
when drawing the line I use :
>> plot(...,'Color',[Color_Vect , Alpha],'LineWidth',10)
Color_Vect : vector of the colors i.e. [ 1 0 0] . Alpha =0.2.
in another section, when i need to copy the line to another plot I want to extract the alpha value of the line to add it to the new line.
I've been searching in all the values of the Line handles but couldnt find any aplha value.
do anyone knows were is this value stored ??
Rik on 27 Sep 2022
Edited: Rik on 27 Sep 2022
I have no clue why this is hidden, but converting the object to a struct and hunting for a few appropriate candidates I found that h.Edge.ColorData was a 4x1 uint8.
h=plot(rand(1,10),1:10,'Color',[1 0 0 0.2],'LineWidth',10);
Note that this is undocumented, and may be specific to a release and/or OS. This works on my Windows copy, as well as online, but it might only work for R2022b, you'll have to test this on R2019a yourself. Just look for anything that might fit after converting the object to a struct.