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SUBROUTINE PLTFV2 (V1,VDX,VDY,V2, XX,YY, MX,MY, NX,NY, SCALE,
X PL2)
C$ (Flow Vectors)
C$ Plot a flow vector field in the current viewport. The
C$ arguments are:
C$
C$ (V1,V2)........Range of vector magnitudes. Vectors will be
C$ scaled so that a vector of maximum length V2
C$ will be 1/max(NX,NY) units long on a unit
C$ square window, and vectors of length less
C$ than V1 will not be plotted.
C$ (MX,MY)........Actual declared dimensions of VDX(*,*) and
C$ VDY(*,*).
C$ (NX,NY)........Cross-sections of VDX(*,*) and VDY(*,*) in
C$ use. For best results, NX and NY should not
C$ exceed about 20.
C$ VDX(I,J).......Vector X-components relative to point
C$ (XX(I),YY(J)).
C$ VDY(*,*).......Vector Y-components relative to point
C$ (XX(I),YY(J)).
C$ XX(*)..........X-components.
C$ YY(*)..........Y-components.
C$ SCALE..........SCALE(X) is a function which is used to
C$ scale the length of a vector. "ABS" will
C$ give linear scaling, while "SQRT", "ATAN",
C$ and "TANH" achieve a compression which is
C$ often useful to avoid small vectors being
C$ reduced to bare points.
C$ PL2............2-dimensional pen movement routine, perhaps
C$ PL2CA.
C$
C$ (VDX(I,J),VDY(I,J)) together define a flow vector at the
C$ point (XX(I),YY(J)) on a regular grid with non-uniform
C$ spacing. The vectors are plotted with a dot at the point
C$ (XX(I),YY(J)), with the tail of the vector extending away
C$ from the dot.
C$ (06-FEB-85)