NAME

       Surface_params - This document briefly describes the Surface internal parameters.

DESCRIPTION

       There are no parameter access routines available for the Surface utility.  Therefore,
       parameters must be set through the common blocks SRFBLK and SRFIP1.

       In order to access the internal parameters, you must declare the following common blocks
       for the Surface parameters in your code.

        COMMON /SRFBLK/ LIMU(1024) ,LIML(1024) ,CL(41)     ,NCL        ,
       1                LL         ,FACT       ,IROT       ,NDRZ       ,
       2                NUPPER     ,NRSWT      ,BIGD       ,UMIN       ,
       3                UMAX       ,VMIN       ,VMAX       ,RZERO      ,
       4                IOFFP      ,NSPVAL     ,SPVAL      ,BIGEST
        COMMON /SRFIP1/ IFR        ,ISTP       ,IROTS      ,IDRX       ,
       1                IDRY       ,IDRZ       ,IUPPER     ,ISKIRT     ,
       2                NCLA       ,THETA      ,HSKIRT     ,CHI        ,
       3                CLO        ,CINC       ,ISPVAL

       Note that not all of the variables declared above are considered user-modifiable
       parameters.  Definitions of only user-modifiable parameters follow:

       IFR         -1   Call FRAME first.
                    0   Do not call FRAME.
                   +1   Call FRAME when done (default).

       ISTP        -1   Draws alternating frames, slightly offset
                        (For movies, IROTS = 0).
                    0   Blank frame between for stereo slide (IROTS = 1)
                        (default).
                   +1   Both on same frame. (left picture to left
                        side. IROTS = 0).

       IROTS
                    0   +Z in vertical plotting direction (CINE mode)
                        (default).
                   +1   +Z in horizontal plotting direction (COMIC mode).

       IDRX        +1   Draw lines of constant X (default).
                    0   Do not.

       IDRY        +1   Draw lines of constant Y (default).
                    0   Do not.

       IDRZ        +1   Draw lines of constant Z (contour lines).
                    0   Do not (default).

       IUPPER      +1   Draw upper side of surface.
                    0   Draw both sides (default).
                   -1   Draw lower side.

       ISKIRT      +1   Draw a skirt around the surface.
                        BOTTOM = HSKIRT.
                    0   Do not (default).

       NCLA
                        Approximate number of levels of constant Z
                        that are drawn if levels are not specified.
                        40 is the maximum and 6 is the default.

       THETA
                        The angle in radians between eyes for stereo pairs.
                        The default is .02.

       HSKIRT
                        Height of skirt (if ISKIRT = 1). The default is 0.

       CHI
                        Highest level of constant Z. The default is 0.

       CLO
                        Lowest level of constant Z. The default is 0.

       CINC
                        Increment between levels. The default is 0.

       IOFFP
                        Flag to control the use of the special value feature. Do
                        not have both IOFFP=1 and ISKIRT=1.
                    0   Feature not in use (default).
                   +1   Feature in use.  No lines are drawn to data points
                        that are equal to SPVAL.

       SPVAL
                        Special value used to mark unknown data when
                        IOFFP=1.  The default is 0.

SEE ALSO

       Online: surface, ezsrfc, pwrzs, setr, srface.  ncarg_cbind.

       Hardcopy: NCAR Graphics Fundamentals, UNIX Version

COPYRIGHT

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