ncl_conop3(3)

1CONOP3(3NCARG)                   NCAR GRAPHICS                  CONOP3(3NCARG)
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NAME

6       CONOP3 - sets option switches and specifys various REAL parameters to
7       be used by the Conran_family utility.
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SYNOPSIS

10       CALL CONOP3 (IOPT, ARRAY, LENA)
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DESCRIPTION

13       IOPT        Character, input -- Selects an internal parameter and sets
14                   an option switch.  The possibilities are:
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16                    'CHL=ON' or 'CHL=OFF'
17                    'CIL=ON' or 'CIL=OFF'
18                    'CON=ON' or 'CON=OFF'
19                    'DBP=ON' or 'DBP=OFF'
20                    'SDC=ON' or 'SDC=OFF'
21                    'SLD=ON' or 'SLD=OFF'
22                    'TEN=ON' or 'TEN=OFF'
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24       ARRAY       Real array, input -- Sets an internal parameter.
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26       LENA        Integer, input -- The length of array ARRAY.
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28                   If an option is turned 'ON', then the remaining CONOP3
29                   arguments can be used to override the default settings of
30                   that option.
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32                   If the option is 'OFF', then the remaining arguments of the
33                   CONOP3 call can be any dummy values.  Option settings will
34                   be returned to their default values.
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36                   The following options are defined by this subroutine:
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38       CHL     This parameter determines how the high and low contour values
39               are set.  These contour values may be set by the program or by
40               the user.  If CHL=OFF, the program examines the user's input
41               data and determines both the high and low values.  If CHL=ON,
42               the user must specify the desired high (HI) and low (FLO)
43               values.  The default is CHL=OFF.
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45               If program set: CALL CONOP3('CHL=OFF',0.,0)
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47               If user set: CALL CONOP3('CHL=ON',ARRAY,2) where ARRAY(1)=HI,
48               ARRAY(2)=FLO
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50               Note: The values supplied for contour increment and contour
51               high and low values assume unscaled data values.  See the SDC
52               parameter, below.
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54       CIL     This parameter determines how the contour increment (CINC) is
55               set.  The increment is either calculated by the program
56               (CIL=OFF) using the range of high and low values from the
57               user's input data, or set by the user (CIL=ON).  The default is
58               CIL=OFF.
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60               If program set: CALL CONOP3('CIL=OFF',0.,0)
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62               If user set:  CALL CONOP3('CIL=ON',CINC,1)
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64               Note: By default, ('CIL=OFF') the program will examine the
65               user's input data and determine the contour interval (CINC) at
66               some appropriate range between the level of high and low values
67               supplied, usually generating between 15 and 20 contour levels.
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69               Example:   CALL CONOP3('CIL=ON',10.,1)
70               will generate contours at increments of 10. units in user
71               coordinates.
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73       CON     This parameter determines how the contour levels are set.  If
74               CON=ON, the user must specify an array of contour values and
75               the number of contour levels.  A maximum of NCL=30 contour
76               levels is permitted.  If CON=OFF, NCL and the contour values
77               are computed.  The default is OFF.
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79               If program set: CALL CONOP3('CON=OFF',0.,0)
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81               If user set: CALL CONOP3('CON=ON',ARRAY,NCL)
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83               Note: The real array (ARRAY) must have the contour levels
84               ordered from smallest to largest.
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86               Warning: It is illegal to use the CON option when either CIL or
87               CHL are activated.  If this is done, the option call that
88               detected the error will not be executed.
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90       DBP     This parameter determines how the dash pattern break point (BP)
91               is set.  (Does not apply to entry CONRAQ.)  If DBP=ON, BP must
92               be set by the user.  If DBP=OFF, the program will set BP to 0.
93               This is the default.
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95               If program set: CALL CONOP3('DBP=OFF',0.,0)
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97               If user set:  CALL CONOP3('DBP=ON',BP,1)
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99               Note: BP is a floating point number where the break for GTR and
100               LSS contour dash patterns are defined.  BP is assumed to be
101               given relative to the untransformed contours.
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103               To see how various dash line patterns can be assigned to
104               various contours see parameter DBP in "man conop4".
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106       SDC     The parameter to determine how to scale the input data from
107               which the contours are generated.  (Does not apply to entry
108               CONRAQ.)  If SDC=ON, the scaling factor is set to ARRAY(1).  If
109               SDC=OFF, the default scale factor of 1. is used.
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111               If program set: CALL CONOP3('SDC=OFF',0.,0)
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113               If user set:  CALL CONOP3('SDC=ON',ARRAY,1)
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115               Note: The data plotted on contour lines and the data plotted
116               for relative minimums and maximums will be scaled by ARRAY.
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118       SLD     Input a polygon to define the extent of area to be contoured.
119               (Does not apply to entry CONRAQ.)  When this option is
120               activated, only those contours within the shield are drawn.
121               The shield is a polygon specified by the user which must be
122               given in the same coordinate range as the the data.  It must
123               define only one polygon.
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125               To input a shield:
126                 CALL CONOP3('SLD=ON',ARRAY,LENA)
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128               Otherwise:
129                 CALL CONOP3('SLD=OFF',0.,0)
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131               Note: ARRAY is a real array LENA elements long.  The first
132               LENA/2 elements are X coordinates and the second LENA/2
133               elements are Y coordinates.  This polygon must be closed, that
134               is the first and last points in ARRAY must be the same.
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136               Example:
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138                DIMENSION SHLD(10)
139                DATA SHLD/ 7.,10.,10.,7.,7.,
140               1            7.,7.,10.,10.,7./
141                CALL CONOP3 ('SLD=ON',SHLD,10)
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143       TEN     The parameter to determine the tension factor applied when
144               smoothing contour lines using splines under tension.  (Does not
145               apply to entry CONRAQ.)  If user set, the allowed range is from
146               greater than zero to 30.  The higher the tension the less
147               smoothing occurs.  The default value (TEN=OFF) is 2.5.
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149               If program set: CALL CONOP3('TEN=OFF',0.,0)
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151               If user set:  CALL CONOP3('TEN=ON',TENS,1)
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153               Note: This option is not available in the standard version of
154               CONRAN.
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USAGE

157       CONOP3 is called to set parameters of type REAL before CONRAN, CONRAQ,
158       or CONRAS are called to generate the contour plot.
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EXAMPLES

161       Use the command ncargex to see the following examples: tconaq, tconan,
162       and tconas.
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ACCESS

165       To use CONOP3 load the NCAR Graphics libraries ncarg, ncarg_gks, and
166       ncarg_c, preferably in that order.
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MESSAGES

169       See the conran_family man page for a description of all Conran_family
170       error messages and/or informational messages.
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COPYRIGHT

180       Copyright (C) 1987-2009
181       University Corporation for Atmospheric Research
182       The use of this Software is governed by a License Agreement.
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186UNIX                              March 1993                    CONOP3(3NCARG)