Ulf A. S. Holbrook

I'm trying to implement the Henon Phase Diagram using expr.

http://paulbourke.net/fractals/henonphase/

This code is the first of the two equations:

"expr $f1*cos($f2)-($f3-pow($f1))*sin($f2)"

And this gives me the error message "function "pow" needs two arguments." And I cannot seem to solve it. Could anyone shed some light on this?

henon-phase-diagram

expr $f1*cos($f2)-($f3-pow($f1,2))*sin($f2)

the pow function needs two arguments, didn't check the link but i suppose it's the square of $f1 you want ? hence the 2. if that doesn't work, try interverting 2 and $f1.

Henon phase diagram