how to use a color using a set analysis in a chart

[olivierrobin]

hello,

I have a chart with 1 dimension and 3 measures (cf picture 1)

one of them should display an colored arrow depending  on the sign of a ratio based on the values of the row (and of course the color used depends on the dimension value)

I use a formula like :

pick(sign(....)+2, color if negative, color if 0, color if postive)

where color is negative is :

only({<_Indicateur=p({$} _Indicateur_3),_Lib_Indicateur=>} rgb_moins)

if I put this formula in a column expression, it retrieves the correct value (for ex: rgb(134,175,73)) (cf pic2)

put if I use it in text color formula, it has no effect, even if I enclose it into $(=)

As it is a set analysis, I wonder if it is not evaluated once ans so the result is based on the first value.

Any idea to achieve this  ?