ncl_dpsmth (3) - Linux Manuals

ncl_dpsmth: Used to draw a curve when fractional coordinates are available and

NAME

DPSMTH - Used to draw a curve when fractional coordinates are available and smoothing is to be done.

SYNOPSIS

CALL DPSMTH (XCPF,YCPF,IFVL)

C-BINDING SYNOPSIS

#include <ncarg/ncargC.h>

void c_dpsmth (float xcpf, float ycpf, int ifvl);

DESCRIPTION

XCPF

(an input expression of type REAL) specifies the X coordinate of a point in the fractional coordinate system. Ignored when IFVL = 2.

YCPF

(an input expression of type REAL) specifies the Y coordinate of a point in the fractional coordinate system. Ignored when IFVL = 2.

IFVL

(an input expression of type INTEGER) indicates what type of call is being done: "0" implies a "first-point" call, "1" implies a "vector" call, and "2" implies a "last-point" or "buffer-flush" call.

C-BINDING DESCRIPTION

The C-binding argument descriptions are the same as the FORTRAN argument descriptions.

USAGE

Use "CALL DPSMTH(XCPF,YCPF,0)" to do a "pen-up" move to the first point in a sequence of points defining a curve.

Use "CALL DPSMTH(XCPF,YCPF,1)" to do "pen-down" moves to the second and following points in a sequence of points defining a curve.

Use "CALL DPSMTH(0.,0.,2) to terminate a sequence of calls, finish drawing the curve, and flush internal buffers.

DPSMTH accumulates points until it has an internal buffer-load or until the last one has been received. It then creates a smooth curve passing through all the points, interpolates points along that smooth curve, and passes those points along to the routine DPDRAW. If the internal parameter 'TCS' has a value less than or equal to zero, the smoothing is done using simple cubic splines; if 'TCS' has a value greater than zero, the smoothing is done using cubic splines under tension and 'TCS' specifies the desired tension.

EXAMPLES

Use the ncargex command to see the following relevant examples: tdshpk.

ACCESS

To use DPSMTH or c_dpsmth, load the NCAR Graphics libraries ncarg, ncarg_gks, and ncarg_c, preferably in that order.

COPYRIGHT

Copyright (C) 1987-2009
University Corporation for Atmospheric Research
The use of this Software is governed by a License Agreement.