thank you for that quick answer but ;
mr:=MyRSISeries(#Close,14);
PlotSeries(mr,pane1,#red,#thick);
PlotSeries(RSISeries(#Close,14),pane1,#Green,#Thin);
PlotSeries(RSISeries(#Close,15),pane1,#Green,#Thin);
PlotSeries(RSISeries(#Close,13),pane1,#Green,#Thin);
The lines dont cover at all, they are not even swinging together. built-in rsi seems to have different function?
look at this screenshoot:
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blue is my calculation
green is built-in
red is from fundtimer.