[pstricks] psplot, parametricplot, FPset and FPupn

[Juergen Rose]

Hallo Herbert,

I try to draw a archimedean spiral for several hours, where the
parameters \dou is calculated with the fp-package. My TeX fragment looks
like:

    \FPmul\phimax\parq{90}
        \FPupn\rmax{\phiend{} \pard{} * 1 +}
        \FPround\dout\pard 2
        
        \begin{pspicture}(-\rmax,-\rmax)(\rmax,\rmax)
           \psaxes[Dx=1.0,Dy=1.0]{->}(0,0)(-\rmax,-\rmax)(\rmax,\rmax)
           \parametricplot{0}{\phimax}{%
              /k \dou 180 div def t cos t mul k mul t sin t mul k mul}
           \uput[-45](\rmax,-1.0){$x$}
           \uput[180](1.0,\rmax){$y$}
           \rput[l](\rmax,\rmax){$\mathbf{f(r)= \frac{\rfaktor
        \phi}{\pi}}$}
        \end{pspicture}

TeX does not complain about errors. If I try to view the resulting
PS-file with gv, the axes are shown, but then says gv:

ERROR: /typecheck in --div--
Operand stack:
   k   180
Execution stack:
   %interp_exit   .runexec2   --nostringval--   --nostringval--
--nostringval--   2   %stopped_push   --nostringval--   --nostringval--
--nostringval--   false   1   %stopped_push   1   3   %oparray_pop   1
3   %oparray_pop   1   3   %oparray_pop   1   3   %
oparray_pop   .runexec2   --nostringval--   --nostringval--
--nostringval--   2   %stopped_push   --nostringval--   --nostringval--
Dictionary stack:
   --dict:1120/1686(ro)(G)--   --dict:0/20(G)--   --dict:82/200(L)--
--dict:189/300(L)--   --dict:38/200(L)--   --dict:89/200(L)--
Current allocation mode is local
ESP Ghostscript 815.02: Unrecoverable error, exit code 1

If I replace \dou by some value like 1.2, it works fine. It looks if
parametricplot can not work with the values set by FPset odr calculated
by FPupn. Any hints are appreciated,

	regards Juergen




-- 
Juergen Rose <rose at rz.uni-potsdam.de>
TFH-Wildau