<!-- Creator : groff version 1.19.2 --> <!-- CreationDate: Tue Mar 8 16:22:23 2011 --> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta name="generator" content="groff -Thtml, see www.gnu.org"> <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> <meta name="Content-Style" content="text/css"> <style type="text/css"> p { margin-top: 0; margin-bottom: 0; } pre { margin-top: 0; margin-bottom: 0; } table { margin-top: 0; margin-bottom: 0; } </style> <title>GRDCLIP</title> </head> <body bgcolor="#ffffff"> <h1 align=center>GRDCLIP</h1> <a href="#NAME">NAME</a><br> <a href="#SYNOPSIS">SYNOPSIS</a><br> <a href="#DESCRIPTION">DESCRIPTION</a><br> <a href="#OPTIONS">OPTIONS</a><br> <a href="#GRID FILE FORMATS">GRID FILE FORMATS</a><br> <a href="#EXAMPLES">EXAMPLES</a><br> <a href="#SEE ALSO">SEE ALSO</a><br> <hr> <a name="NAME"></a> <h2>NAME</h2> <p style="margin-left:11%; margin-top: 1em">grdclip − Clipping of range in grid files.</p> <a name="SYNOPSIS"></a> <h2>SYNOPSIS</h2> <p style="margin-left:11%; margin-top: 1em"><b>grdclip</b> <i>input_file.grd</i> <b>−G</b><i>output_file.grd</i> [ <b>−Sa</b><i>high/above</i> ] [ <b>−Sb</b><i>low/below</i> ] [ <b>−V</b> ]</p> <a name="DESCRIPTION"></a> <h2>DESCRIPTION</h2> <p style="margin-left:11%; margin-top: 1em"><b>grdclip</b> will set values < <i>low</i> to <i>below</i> and/or values > <i>high</i> to <i>above</i>. Useful when you want all of a continent or an ocean to fall into one color or grayshade in image processing, or clipping of the range of data values is required. <i>above/below</i> can be any number or NaN (Not a Number). You must choose at least one of <b>−Sa</b> or <b>−Sb</b>. <i><br> input_file.grd</i></p> <p style="margin-left:22%;">The input 2-D binary grid file.</p> <table width="100%" border=0 rules="none" frame="void" cellspacing="0" cellpadding="0"> <tr valign="top" align="left"> <td width="11%"></td> <td width="3%"> <p style="margin-top: 1em" valign="top"><b>−G</b></p> </td> <td width="8%"></td> <td width="75%"> <p style="margin-top: 1em" valign="top"><i>output_file.grd</i> is the modified output grid file.</p></td> <td width="3%"> </td> </table> <a name="OPTIONS"></a> <h2>OPTIONS</h2> <table width="100%" border=0 rules="none" frame="void" cellspacing="0" cellpadding="0"> <tr valign="top" align="left"> <td width="11%"></td> <td width="4%"> <p style="margin-top: 1em" valign="top"><b>−Sa</b></p> </td> <td width="7%"></td> <td width="78%"> <p style="margin-top: 1em" valign="top">Set all data[i] > <i>high</i> to <i>above</i>.</p></td> <tr valign="top" align="left"> <td width="11%"></td> <td width="4%"> <p style="margin-top: 1em" valign="top"><b>−Sb</b></p> </td> <td width="7%"></td> <td width="78%"> <p style="margin-top: 1em" valign="top">Set all data[i] < <i>low</i> to <i>below</i>.</p></td> <tr valign="top" align="left"> <td width="11%"></td> <td width="4%"> <p style="margin-top: 1em" valign="top"><b>−V</b></p> </td> <td width="7%"></td> <td width="78%"> <p style="margin-top: 1em" valign="top">Selects verbose mode, which will send progress reports to stderr [Default runs "silently"].</p></td> </table> <a name="GRID FILE FORMATS"></a> <h2>GRID FILE FORMATS</h2> <p style="margin-left:11%; margin-top: 1em">By default <b><A HREF="GMT.html">GMT</A></b> writes out grid as single precision floats in a COARDS-complaint netCDF file format. However, <b><A HREF="GMT.html">GMT</A></b> is able to produce grid files in many other commonly used grid file formats and also facilitates so called "packing" of grids, writing out floating point data as 2- or 4-byte integers. To specify the precision, scale and offset, the user should add the suffix <b>=</b><i>id</i>[<b>/</b><i>scale</i><b>/</b><i>offset</i>[<b>/</b><i>nan</i>]], where <i>id</i> is a two-letter identifier of the grid type and precision, and <i>scale</i> and <i>offset</i> are optional scale factor and offset to be applied to all grid values, and <i>nan</i> is the value used to indicate missing data. When reading grids, the format is generally automatically recognized. If not, the same suffix can be added to input grid file names. See <b><A HREF="grdreformat.html">grdreformat</A></b>(1) and Section 4.17 of the GMT Technical Reference and Cookbook for more information.</p> <p style="margin-left:11%; margin-top: 1em">When reading a netCDF file that contains multiple grids, <b><A HREF="GMT.html">GMT</A></b> will read, by default, the first 2-dimensional grid that can find in that file. To coax <b><A HREF="GMT.html">GMT</A></b> into reading another multi-dimensional variable in the grid file, append <b>?</b><i>varname</i> to the file name, where <i>varname</i> is the name of the variable. Note that you may need to escape the special meaning of <b>?</b> in your shell program by putting a backslash in front of it, or by placing the filename and suffix between quotes or double quotes. The <b>?</b><i>varname</i> suffix can also be used for output grids to specify a variable name different from the default: "z". See <b><A HREF="grdreformat.html">grdreformat</A></b>(1) and Section 4.18 of the GMT Technical Reference and Cookbook for more information, particularly on how to read splices of 3-, 4-, or 5-dimensional grids.</p> <a name="EXAMPLES"></a> <h2>EXAMPLES</h2> <p style="margin-left:11%; margin-top: 1em">To set all values > 70 to NaN and all values < 0 to 0 in file data.grd:</p> <p style="margin-left:11%; margin-top: 1em"><b>grdclip</b> data.grd <b>−G</b>new_data.grd <b>−Sa</b>70/NaN <b>−Sb</b>0/0 <b>−V</b></p> <a name="SEE ALSO"></a> <h2>SEE ALSO</h2> <p style="margin-left:11%; margin-top: 1em"><i><A HREF="GMT.html">GMT</A></i>(1), <i><A HREF="grdlandmask.html">grdlandmask</A></i>(1), <i><A HREF="grdmask.html">grdmask</A></i>(1), <i><A HREF="grdmath.html">grdmath</A></i>(1), <i><A HREF="grd2xyz.html">grd2xyz</A></i>(1), <i><A HREF="xyz2grd.html">xyz2grd</A></i>(1)</p> <hr> </body> </html>