
                    The OpenGrADS Bundle Distribution
                    ---------------------------------

                          http://opengrads.org

                          GrADS Version 2.0.1
                        Released 25 October 2011

This OpenGrADS version is based on COLA's 2.0.0 release with very
minor updates in the OpenGrADS extensions; see below for the OpenGrADS
features that extend the standard GrADS functionality provided by
COLA.

As for the new functionality in the COLA release we quote from Jennifer
Adams' announcement of GrADS v2.0.0:

   "Brian and I are pleased to announce a new release of GrADS,
   version 2.0.0. We have worked very hard to make this version as
   stable as possible, and are therefore taking it out of alpha
   status, skipping over beta altogether, and calling it
   'operational'. There is a very long list of new features, bug fixes
   and miscellaneous additions, the full text from the ChangeLog is
   below, please read it carefully.

   Highlights of this release, other than its stability, are a new
   shaded contouring algorithm (which allows for "transparent"
   colors), support for polygon shapefiles and KML files, and some
   fixes and improvements to the streamlines, including controls for
   spacing, style, and size of the arrows. There are also new versions
   of some of the supplibs, enabling the handling of GRIB2 product
   definition template 4.15, and optimizing the netcdf5/hdf5
   interface."

Consult the ChangeLog file for detailed list of new features and bug
fixes.


OpenGrADS Features
------------------

Several other important OpenGrADS additions are available with this version:

- this is an OpenGrADS Bundle release, a relocatable, minimum
  configuration package that has all that you need to run GrADS. See
  INSTALL for additonal information.

- preview release of the OpenGrADS Extensions; the same extensions 
  available in GrADS v1.9.0-rc1 are now available with GrADS v2.0.

  Caveat: as COLA is yet to publish the official API for User Defined
          functions in GrADS v2.0 we have adopted here an API that
          is based on our work vith v1.9.0-rc1. This is a very low-level
          API that is *not* endorsed by COLA. As such, it is *not* advisable 
          that users adopt this API to write their own extensions.

- These extensions are still being fully tested. Please report any problems
  you encounter. Use them at your own risk.
        
- The following extensions are included: see below.


Documentation and Additional Information
----------------------------------------

Consult 
           OpenGrADS Website: http://opengrads.org
               GrADS Website: http://grads.iges.org/grads
                          
                      ---------------------        
                      User Defined Commands
                      ---------------------        


   Command            Environment Variables               Function@Library
 ----------- ---------------------------------------  --------------------------
 printenv    Expand environment variables             c_xenv@^env.gex
 runenv      Expand env vars and run command          c_env@^env.gex
 @           Expand env vars and run command          c_env@^env.gex
 getenv      Get value of environment variable        c_getenv@^env.gex
 setenv      Set value of environment variable        c_setenv@^env.gex

   Command           GxYAT: Image Generation              Function@Library
 ----------- ---------------------------------------  --------------------------
 gxyat       Save images in PNG/SVG/PDF/PS            c_gxyat@^gxyat.gex
 set_rgba    Set color red/green/blue/alpha           c_rgba@^gxyat.gex

   Command           Simple Extension Example             Function@Library
 ----------- ---------------------------------------  --------------------------
 hello       Hello, World! sample command             c_hello@^libhello.gex

   Command          Interprocess Communication            Function@Library
 ----------- ---------------------------------------  --------------------------
 ipc_verb    IPC verbose toggle                       c_Verb@^libipc.gex
 ipc_open    Open stream for save/load                c_Open@^libipc.gex
 ipc_close   Close stream                             c_Close@^libipc.gex
 ipc_save    Save expression to stream                c_Save@^libipc.gex
 ipc_define  Define variable (obsolete)               c_Define@^libipc.gex
 ipc_error   Print IPC error message                  c_Error@^libipc.gex

   Command    LATS: File Reformatting and Subsetting      Function@Library
 ----------- ---------------------------------------  --------------------------
 set_lats    Set LATS parameters                      c_lats_set@^liblats.gex
 query_lats  Query LATS parameters                    c_lats_query@^liblats.gex
 lats_grid   Define LATS grid                         c_lats_grid@^liblats.gex
 lats_data   Write data to LATS file                  c_lats_data@^liblats.gex
 reinit_lats Re-init LATS parameters                  c_lats_reinit@^liblats.gex

   Command          Mike Fiorino's Extensions             Function@Library
 ----------- ---------------------------------------  --------------------------
 mfhilo      Find max/min or H/L in 2D field          c_mfhilo@^libmf.gex
 tcprop      Properties radinf from central lon/lat   c_tcprop@^libmf.gex
 grhist      histogram of expr                        c_grhist@^libmf.gex

   Command          Satellite Orbit Extensions            Function@Library
 ----------- ---------------------------------------  --------------------------
 set_orb     Set ORB parameters                       c_set@^orb.gex
 orb_track   Satellite ground tracks                  c_track@^orb.gex


                      ----------------------       
                      User Defined Functions
                      ----------------------       

  Function         Ben-Jei Tsuang's Extensions            Function@Library
 ----------- ---------------------------------------  --------------------------
 lt          Local time                               f_bjt@^libbjt.gex
 jd          Julian day                               f_bjt@^libbjt.gex
 cosz        Cosine solar zenith angle                f_bjt@^libbjt.gex
 dayratio    Daylight ratio                           f_bjt@^libbjt.gex
 if          Conditional function                     f_bjt@^libbjt.gex
 maxv        Maximum value                            f_bjt@^libbjt.gex
 minv        Minimum value                            f_bjt@^libbjt.gex
 which       Label gridpoints                         f_bjt@^libbjt.gex
 ftest       F-test                                   f_bjt@^libbjt.gex
 ttest       T-test                                   f_bjt@^libbjt.gex
 tfit        Point  linear regression                 f_bjt@^libbjt.gex
 fit         Global linear regression                 f_bjt@^libbjt.gex
 tcorr2      Time correlation                         f_bjt@^libbjt.gex
 tregr2      Point linear regression                  f_bjt@^libbjt.gex
 tmave2      Time averaging w/masking                 f_bjt@^libbjt.gex
 madvu       Calculates -d(u*EXPR)/dx                 f_bjt@^libbjt.gex
 madvv       Calculates -d(V*EXPR)/dy                 f_bjt@^libbjt.gex
 madvw       Calculates -d(W*EXPR)/dp                 f_bjt@^libbjt.gex
 muadv       Zonal advection                          f_bjt@^libbjt.gex
 mvadv       Meridional advection                     f_bjt@^libbjt.gex
 mwadv       Vertical advection                       f_bjt@^libbjt.gex
 satvap      Saturated vapor pressure                 f_bjt@^libbjt.gex
 dew         Dew point temperature                    f_bjt@^libbjt.gex
 lw          Thermal infrared fluxes                  f_bjt@^libbjt.gex
 lw2         Thermal infrared fluxes v2               f_bjt@^libbjt.gex
 pinterp     Pressure interpolation                   f_bjt@^libbjt.gex
 zinterp     Height interpolation                     f_bjt@^libbjt.gex
 line        Draws a line                             f_bjt@^libbjt.gex
 vint2       Mass-weighted vertical integral          f_bjt@^libbjt.gex

  Function     Streamfunction & Velocity Potential        Function@Library
 ----------- ---------------------------------------  --------------------------
 fish        Poisson solver                           f_fish@^fish.gex
 fish_psi    Compute streamfunction                   f_psichi@^fish.gex
 fish_chi    Compute velocity potential               f_psichi@^fish.gex
 fish_vor    Compute vorticity                        f_psichi@^fish.gex
 fish_div    Compute divergence                       f_psichi@^fish.gex

  Function       Saakeskus Wx Function Collection         Function@Library
 ----------- ---------------------------------------  --------------------------
 dewpt       Dew-point temperature                    f_gsudf@^gsudf.gex
 ept         Equivalent potential temperature         f_gsudf@^gsudf.gex
 epi         Potential Instability                    f_gsudf@^gsudf.gex
 plcl        Pressure at LCL                          f_gsudf@^gsudf.gex
 shear       Wind Shear                               f_gsudf@^gsudf.gex
 srh1km      Storm-relative Helicity 0-1km'           f_gsudf@^gsudf.gex
 srh3km      Storm-relative Helicity 0-3km'           f_gsudf@^gsudf.gex
 tlcl        Temperature at LCL                       f_gsudf@^gsudf.gex
 tsindex     Chance of T-storm Initiation             f_gsudf@^gsudf.gex
 ttindex     Total Totals Index                       f_gsudf@^gsudf.gex
 wchill      Wind Chill Index (New)                   f_gsudf@^gsudf.gex

  Function           Simple Extension Example             Function@Library
 ----------- ---------------------------------------  --------------------------
 hello       Hello, World! sample function            f_hello@^libhello.gex

  Function          Interprocess Communication            Function@Library
 ----------- ---------------------------------------  --------------------------
 ipc_save    Save expression to stream                f_Save@^libipc.gex
 ipc_load    Load variable from file                  f_Load@^libipc.gex

  Function          Mike Fiorino's Extensions             Function@Library
 ----------- ---------------------------------------  --------------------------
 smth2d      Shuman smoother/de-smoother              f_smth2d@^libmf.gex
 uv2trw      Find radial/tangential velocity          f_uv2trw@^libmf.gex
 re2         General interpolator (regrid2)           f_re2@^libmf.gex
 esmrf       Saturation vapor pressure (old MRF)      f_esmrf@^libmf.gex
 linreg      Linear regression: mx + b                f_linreg@^libmf.gex

  Function          Satellite Orbit Extensions            Function@Library
 ----------- ---------------------------------------  --------------------------
 orb_mask    Satellite orbit masking                  f_mask@^orb.gex

  Function             Regridding Functions               Function@Library
 ----------- ---------------------------------------  --------------------------
 re          General interpolator                     ffre@^re.gex
 re_         General interpolator (verbose)           ffre_dbg@^re.gex
 regrid2     regrid2-like wrapper for re()            f_gsudf@^gsudf.gex
 geos        Interpolation to GEOS-5 Grids            f_gsudf@^gsudf.gex
 reimg       Interpolation for Image Generation'      f_gsudf@^gsudf.gex

  Function         Spherical Harmonic Analysis            Function@Library
 ----------- ---------------------------------------  --------------------------
 sh_filt     Spherical harmonic filter                f_shfilt@^shfilt.gex
 sh_power    Spherical harmonic spectra               f_shpowr@^shfilt.gex


                                 I M P O R T A N T
                                 -----------------

The following extension has been discontinued as shapefile support is
now built into GrADS. 

   Command             Shapefile Extensions               Function@Library
 ----------- ---------------------------------------  --------------------------
 shp_lines   Draw lines    from shapefile             c_lines@^shape.gex
 shp_polyf   Draw polygons from shapefile             c_polyf@^shape.gex
