Hi Edward. I gave it a try but I am not sure if this is going to help you. Anyway here is what I found using Fracton to import the formula. It didn't like how a couple of equations were split across two lines so I put them on one line. As John Wilson mentioned c looks suspicious. c exists as an upper case C and later as a lower case c. I don't think FractInt is case sensitive on formulas so those would be the same variable. Fracton converts everything into lower case when importing pars so it makes them the same. I added a parameter section and some colors to see what it would generate. Unfortunately, it gives a black screen. Here is the complete par file that compiles but gives a black screen below: series_circuit { reset=2004 type=formula formulafile=fracton.frm formulaname=DiodeRLC passes=1 float=y center-mag=0/0/2.6666667/1/0/0 params=1/1/0/0/-1/0/1/0/0/0 maxiter=2000 inside=0 periodicity=6 colors=000C10O40ZA0hI0oS0ua0ym0zy0ym0ua0oS0hI0ZA0O\ 40C10000C10O40ZA0hI0oS0ua0ym0zy0ym0ua0oS0hI0ZA0O40\ C10000C10O40ZA0hI0oS0ua0ym0zy0ym0ua0oS0hI0ZA0O40C1\ 0000C10O40ZA0hI0oS0ua0ym0zy0ym0ua0oS0hI0ZA0O40C100\ 00C10O40ZA0hI0oS0ua0ym0zy0ym0ua0oS0hI0ZA0O40C10000\ C10O40ZA0hI0oS0ua0ym0zy0ym0ua0oS0hI0ZA0O40C10000C1\ 0O40ZA0hI0oS0ua0ym0zy0ym0ua0oS0hI0ZA0O40C10000C10O\ 40ZA0hI0oS0ua0ym0zy0ym0ua0oS0hI0ZA0O40C10000C10O40\ ZA0hI0oS0ua0ym0zy0ym0ua0oS0hI0ZA0O40C10000C10O40ZA\ 0hI0oS0ua0ym0zy0ym0ua0oS0hI0ZA0O40C10000C10O40ZA0h\ I0oS0ua0ym0zy0ym0ua0oS0hI0ZA0O40C10000C10O40ZA0hI0\ oS0ua0ym0zy0ym0ua0oS0hI0ZA0O40C10000C10O40ZA0hI0oS\ 0ua0ym0zy0ym0ua0oS0hI0ZA0O40C10000C10O40ZA0hI0oS0u\ a0ym0zy0ym0ua0oS0hI0ZA0O40C10000C10O40ZA0hI0oS0ua0\ ym0zy0ym0ua0oS0hI0ZA0O40C10000C10O40ZA0hI0oS0ua0ym\ 0zy0ym0ua0oS0hI0ZA0O40C10 } frm:DiodeRLC { f=1/real(p1), z=pixel, x=real(z), y=imag(z), p=0.039757, h=0.071743, s=-1, r=1, l=0.001, c=10^6, c=1/c, k=10^23, k=(1.3806485279)/k, twopi=6.283185307179586, t=270, q=10^19, q=(1.602176620898)/q, id=10^12, id=1/id, a1=q/(k*t), b1=(k*t)/(q*c*l), b2=(k*t)/(id*q*l), b3=r/l, t1=0: v=twopi*t1, v=100*sin(w), q=s*a1*x, q=exp(q), u=y, w=s*a1*y*y+s*b2*q*y+s*b3*y+b2*q*w+b1*q+s*b1, a=x+p*u, b=y+p*w, q=s*a1*a, q=exp(q), c=x+h*(u+b), d=y+h*(w+s*a1*b*b+s*b2*q*b+s*b3*b+b2*q*v+b1*q+s*b1), x=c, y=d, t1=t1+f, z=x+flip(y), |y| } -- Mike Frazier www.fracton.org