Scilab keeps plotting an old function

Hello People

On my machine, Scilab's graphics window is 'jammed'.

Scilab keeps plotting an old function; regardless of the code that I use to generate a new plot, an old function continues to be evaluated and plotted into the graphics window. The function involves summation of a few trigonometric terms.

Changing the name of the graphics window doesn't help.

I have tried reinstalling Scilab but the hew installation picks up the same wrong function from "somewhere" and presents it as though it were the output from the current routine.

Thank you

Mark