ncl_pcmequ (3) - Linux Manuals

NAME

PCMEQU - Draws characters of "medium quality". It does this by drawing lines, just as PCHIQU does, but it does not produce quite such fancy characters. No function codes may be used. Using PCMEQU to draw a given string of characters will create a larger metafile than if PCLOQU were used, which may be a disadvantage. However, it may also be more dependable, in that it does not depend on capabilities the translator may or may not have.

PLCHMQ is an alternate name for the routine PCMEQU.

SYNOPSIS

CALL PCMEQU (XPOS,YPOS,CHRS,SIZE,ANGD,CNTR)

C-BINDING SYNOPSIS

#include <ncarg/ncargC.h>

void c_pcmequ (float xpos, float ypos, char *chrs,
float size, float angd, float cntr)

DESCRIPTION

XPOS,YPOS

(input expressions of type REAL) specify positioning coordinates for the characters to be drawn. If the internal parameter 'MA' has the value 0, these are given in the current user coordinate system; otherwise, they are given in an arbitrary X/Y coordinate system, as implied by the value of 'MA' and the nature of the routine CPMPXY. (For example, if 'MA' has the value 1 and the default version of CPMPXY is being used, then XPOS is a longitude, in degrees, and YPOS is a latitude, in degrees.) The argument CNTR (described below) specifies how the characters are to be positioned relative to the point (XPOS,YPOS).

CHRS

(an input constant or variable of type CHARACTER) contains a character string to be drawn. The number of characters in CHRS is taken to be LEN(CHRS); to use characters "m" through "n" from a character variable CHRS, use the FORTRAN-77 substring notation "CHRS(m:n)". The string may include any of the 95 characters space, exclamation point, double quote, pound sign, dollar sign, percent sign, ampersand, apostrophe, left parenthesis, right parenthesis, asterisk, plus sign, comma, minus sign, period, slash, 0-9, colon, semi-colon, less than sign, equals sign, greater than sign, question mark, at sign, A-Z, left square bracket, backslash, right square bracket, hat, underscore, backwards quote, a-z, left curly bracket, vertical bar, right curly bracket, and tilde. Function codes, like those in calls to PCHIQU, may not be used.

SIZE

(an input expression of type REAL) specifies the desired character size. If the internal parameter 'MA' is zero, then the following comments apply:

•

If SIZE is less than or equal to zero, its absolute value specifies the size as a multiple of a default digitized size on a 1024x1024 grid, on which blanks are 16 units wide.

•

If SIZE is greater than zero, but less than one, it specifies the desired width of a blank as a fraction of the distance across the plotter frame. This is the recommended scheme.

•

If SIZE is greater than or equal to one, it specifies the desired width of a blank in plotter coordinates, as defined by default or by a user's call to the SPPS routine SETI. Note that use of the routine SETI is now discouraged.

If 'MA' is nonzero, then SIZE is the desired width of a blank as a value in the X/Y coordinate system in which XPOS and YPOS are given.

Capital letters are 4/6 as wide as a blank and, by default, 7/4 as high as they are wide (the internal parameter 'HW' may be used to change the latter value). The distance from the center of each character to the center of the next is constant and is equal to one blank width.

Note that, if the desired character height ("h") is known, one should use SIZE = (6/7) * h.

SIZE is defined in such a way as to be consistent with PCHIQU. If one changes a "CALL PCHIQU" to a "CALL PCMEQU" (assuming that no function codes are used in the string, of course), the results will be much the same, but the length of the string will be different. If one uses SIZE less than zero and one has reset the PCHIQU internal parameter 'PW' to something other than 16, the difference in the output of the two routines will be greater.

ANGD

(an input expression of type REAL) is the angle, in degrees counterclockwise from the positive X axis, at which the character string is to be written.

CNTR

(an input expression of type REAL) is the centering option, as follows:

•

CNTR = -1. means that (XPOS,YPOS) is the center of the left edge of the first character.

•

CNTR = 1. means that (XPOS,YPOS) is the center of the right edge of the last character.

•

CNTR = s means that (XPOS,YPOS) is a point obtained by linear interpolation along the line joining the two points mentioned above (the first point being associated with the value -1 and the second with the value +1). The value "0." gives the midpoint of the line.

Upon return from PCMEQU, all arguments are unchanged.

C-BINDING DESCRIPTION

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

EXAMPLES

Use the ncargex command to see the following relevant examples: cbex01, epltch, tpltch.

ACCESS

To use PCMEQU or c_pcmequ, 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.