On 16 Oct 1998 00:34:11 GMT, stl137@aol.com (STL137) wrote: >Piecewise functions are very difficult (nay, impossible) to graph on any Z80 >calculators. Really? Just use boolian limiters. For example, if you have the function: F(x) = 2x if X<0 F(x) = X^2 of X >= 0 then all you have to do is. y1 = (2x)/(X<0) y2 = (x^2)/(X>=0) EZ.