mbm_grd2arc
Section:  MB-System 5.0  (1)
Updated:  3 June 2013 
Index


 
NAME

mbm_grd2arc - Macro to convert a GMT
grid file in the GMT NetCDF grid format
to an ArcView ASCII grid.

 
VERSION

Version 5.0

 
SYNOPSIS

mbm_grd2arc -Igrdfile -Oarcfile [-H -Nnodata -V]

 
DESCRIPTION

mbm_grd2arc is a macro to convert a GMT
grid file in the GMT NetCDF grid format
to an ArcView ASCII grid. This allows users to import the grid
into Arc/Info and ArcView. The grids must have the same grid
interval in both longitude and latitude. If the grid was created
using mbgrid or mbmosaic, the -E option
must have been used in that program
to set the grid cell sizes equal (see the mbgrid and mbmosaic
manual pages).



The macro first obtains the bounds, dimensions, and grid
cell size of the grid using the GMT program grdinfo.
The grid dimensions, the lower left position, and the
grid cell size are written to the header of the output
ArcView ASCII grid file.
The macro then uses the GMT program grd2xyz to
dump each of the grid values to a temporary ASCII file.
This temporary file is read and parsed one value at
a time.  Any NaN values are
replaced by the nodata value specified with the -N
option. Each final value is printed to the output file.

 
AUTHORSHIP

David W. Caress (caress@mbari.org)




  Monterey Bay Aquarium Research Institute



Dale N. Chayes (dale@ldeo.columbia.edu)




  Lamont-Doherty Earth Observatory

 
OPTIONS


-H


This "help" flag cause the program to print out a description
of its operation and then exit immediately.
-I


grdname



Sets the filename of the input GMT grid file. This file must be
in the GMT NetCDF GRD format.
-N


nodata



Sets the "no data" value used in the output ASCII file.
Default: nodata = -99999.
-O


arcfile



Sets the filename of the output ArcView ASCII grid.
-V


The -V option causes mbm_grd2arc to print out status messages.


 
EXAMPLES

Suppose that we have used mbgrid to obtain a
topography grid file called KohalaA_bath.grd in the GMT NetCDF
GRD format:

        mbgrid -Idatalist \


                -OKohalaA_bath \


                -R-155.72855/-155.31928/20.09488/20.47645 \


                -E30.0/0m! -A2 -N -G3 -C1 -V




In this case, the -E option was used
to force mbgrid to use equal longitude and latitude
grid cell sizes. See the mbgrid or mbmosaic manual pages for
details on the usage of the -E option in those
programs.

In order to convert KohalaA_bath.grd to an ArcView ASCII grid
so that the data can be imported into the Arc/Info or ArcView
GIS packages, we use the mbm_grd2arc macro:

        mbm_grd2arc -IKohalaA_bath.grd \


                -OKohalaA_bath.asc -V




Running the example above produced the following output:


        Program mbm_grd2arc status:


                Input GRD file:            KohalaA_bath.grd


                Output ArcView ASCII file: KohalaA_bath.asc


                Grid dimensions:  1426  1329


                Grid cell sizes:  0.0002871995719  0.0002871995719


                Grid bounds:      -155.72855  -155.3192906    20.09488  20.47628103



        Generating temporary file...


        Parsing temporary file...


        10% complete


        20% complete


        30% complete


        40% complete


        50% complete


        60% complete


        70% complete


        80% complete


        90% complete


        100% complete


 
SEE ALSO

mbsystem(1), mbgrid(1),
mbmosaic(1), mbm_arc2grd(1), mbm_grid(1)

 
BUGS

Maybe. Maybe not.



 
Index

NAME

VERSION

SYNOPSIS

DESCRIPTION

AUTHORSHIP

OPTIONS

EXAMPLES

SEE ALSO

BUGS

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