PGPLOT Module: PGFUNT -- function defined by X = F(T), Y = G(T)


SUBROUTINE PGFUNT (FX, FY, N, TMIN, TMAX, PGFLAG)
REAL FX, FY
EXTERNAL FX, FY
INTEGER N
REAL TMIN, TMAX
INTEGER PGFLAG

Draw a curve defined by parametric equations X = FX(T), Y = FY(T).


Arguments
FX (external real function): supplied by the user, evaluates
X-coordinate.
FY (external real function): supplied by the user, evaluates
Y-coordinate.
N (input) : the number of points required to define the
curve. The functions FX and FY will each be
called N+1 times.
TMIN (input) : the minimum value for the parameter T.
TMAX (input) : the maximum value for the parameter T.
PGFLAG (input) : if PGFLAG = 1, the curve is plotted in the
current window and viewport; if PGFLAG = 0,
PGENV is called automatically by PGFUNT to
start a new plot with automatic scaling.

Note: The functions FX and FY must be declared EXTERNAL in the
Fortran program unit that calls PGFUNT.