root/MGET/Branches/Jason/PythonPackage/dist/TracOnlineDocumentation/Documentation/ArcGISReference/ArcGISRaster.ToPolygonOutlinesArcGISTable.html @ 842

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Rebuilt installation packages again. This will be merged with the Trunk and released as MGET 0.8a28.
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3<html xmlns="http://www.w3.org/1999/xhtml"><head><link rel="stylesheet" type="text/css" href="81help.css?format=raw" /><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Convert ArcGIS Rasters Listed in Table to Polygon Outlines</title></head><body><table style="margin-top:-1em; margin-bottom:0; padding:0; margin-left:-1em"><tr><td style="background:white"><img width="875" height="70" alt="ArcToolbox banner" src="AHBanner_ArcToolbox.gif?format=raw" /></td></tr></table><h1>Convert ArcGIS Rasters Listed in Table to Polygon Outlines</h1><p></p><p>Converts the ArcGIS rasters listed in a table to lines that outline groups of adjacent raster cells having the same value.</p><br /><p><h2><img width="11" height="11" border="0" src="sm_arrow_down.gif?format=raw" /> Command line syntax</h2></p><div Class="expand" id="id103142">ArcGISRasterToPolygonOutlinesArcGISTable_GeoEco &lt;table&gt; &lt;inputRasterField&gt; &lt;outputFeatureClassField&gt; {simplify} {field} {projectedCoordinateSystem} {geographicTransformation} {NEAREST | BILINEAR | CUBIC} {projectedCellSize} {registrationPoint} {clippingDataset} {clippingRectangle} {mapAlgebraExpression} {where} {orderBy;orderBy...} {directions;directions...} {skipExisting} {basePath} <br /><br /><b>Parameters</b><br /><table width="100%" border="0" cellpadding="5"><tbody><tr><th width="40%"><b>Expression</b></th><th width="60%"><b>Explanation</b></th></tr><tr><td class="info">&lt;table&gt;</td><td class="info" align="left"><p>Table to query.</p></td></tr><tr><td class="info">&lt;inputRasterField&gt;</td><td class="info" align="left"><p>Field containing the rasters to convert.</p><p>The rasters will be converted to polygon feature classes using the
4ArcGIS Raster to Polygon tool, and then to line features using the
5Feature to Line tool. The Raster to Polygon tool can only convert
6integer rasters to polygons. If the input rasters are floating-point
7rasters, you must use the Map Algebra Expression parameter to convert
8them to integer rasters.</p></td></tr><tr><td class="info">&lt;outputFeatureClassField&gt;</td><td class="info" align="left"><p>Field containing the output line feature classes.</p><p>One feature class will be created per raster. Missing directories the
9output paths will be created if they do not exist.</p></td></tr><tr><td class="info">{simplify}</td><td class="info" align="left"><p>Determines if the output polygons will be smoothed into simpler
10shapes or conform to the input raster's cell edges.</p><ul><li><p>True - The polygons will be smoothed into simpler shapes. This is
11the default.</p></li></ul><ul><li><p>False - The polygons will conform to the input raster's cell edges.</p></li></ul></td></tr><tr><td class="info">{field}</td><td class="info" align="left"><p>The field used to assign values from the cells in the input raster
12to the lines in the output dataset. It can be an integer or a
13string field.</p></td></tr><tr><td class="info">{projectedCoordinateSystem}</td><td class="info" align="left"><p>New coordinate system to project the raster to.</p><p>The raster may only be projected to a new coordinate system if the
14original projection is defined. An error will be raised if you specify
15a new coordinate system without defining the original coordinate
16system.</p><p>The ArcGIS Project Raster tool is used to perform the projection. The
17documentation for that tool recommends that you also specify a cell
18size for the new coordinate system.</p><p>I have noticed that for certain coordinate systems the ArcGIS 9.2
19Project Raster tool seems to clip the projected raster to an arbitrary
20extent that is too small. For example, when projecting a global MODIS
21Aqua 4 km chlorophyll image in geographic coordinates to
22Lambert_Azimuthal_Equal_Area with central meridian of -60 and latitude
23of origin of -63, the resulting image is clipped to show only
24one-quarter of the planet. This problem does not occur when Project
25Raster is invoked interactively from the ArcGIS user interface; it
26only occurs when the tool is invoked programmatically (the
27ProjectRaster_management method of the geoprocessor). Thus you may
28not see it when you use Project Raster yourself but it may happen when
29you use MGET tools that invoke Project Raster as part of their
30geoprocessing operations.</p><p>If you encounter this problem, you can work around it like this:</p><ul><li><p>First, run this tool without specifying a new coordinate system, to
31obtain the raster in the original coordinate system.</p></li></ul><ul><li><p>In ArcCatalog, use the Project Raster tool to project the raster to
32the new coordinate system. Verify that the entire raster is present,
33that it has not been clipped to an extent that is too small.</p></li></ul><ul><li><p>In ArcCatalog, look up the extent of the projected raster by
34right-clicking on it in the catalog tree, selecting Properties, and
35scrolling down to Extent.</p></li></ul><ul><li><p>Now, before running the MGET tool that projects the raster, set the
36Extent environment setting to the values you looked up. If you are
37invoking the MGET tool interactively from ArcCatalog or ArcMap,
38click the Environments button on the tool's dialog box, open General
39Settings, change the Extent drop-down to "As Specified Below", and
40type in the values you looked up. If you're invoking it from a
41geoprocessing model, right-click on the tool in the model, select
42Make Variable, From Environment, General Settings, Extent. This will
43place Extent as a variable in your model, attached to the MGET tool.
44Open the Extent variable, change it to "As Specified Below" and type
45in the values you looked up. If you're invoking the MGET tool
46programmatically, you must set the Extent property of the
47geoprocessor to the values you looked up. Please see the ArcGIS
48documentation for more information about this and Environment
49settings in general.</p></li></ul><ul><li><p>Run the MGET tool. The extent of the raster should now be the
50proper size.</p></li></ul></td></tr><tr><td class="info">{geographicTransformation}</td><td class="info" align="left"><p>A transformation method used to convert between the original
51coordinate system and the new coordinate system.</p><p>This parameter is a new option introduced by ArcGIS 9.2. You must have
52ArcGIS 9.2 to use this parameter.</p><p>This parameter is only needed when you specify that the raster should
53be projected to a new coordinate system and that new system uses a
54different datum than the original coordinate system, or there is some
55other difference between the two coordinate systems that requires a
56transformation. To determine if a transformation is needed, I
57recommend the following procedure:</p><ul><li><p>First, run this tool without specifying a new coordinate system, to
58obtain the raster in the original coordinate system.</p></li></ul><ul><li><p>Next, use the ArcGIS 9.2 Project Raster tool on the raster to
59project it to the desired coordinate system. If a geographic
60transformation is needed, that tool will prompt you for one. Write
61down the exact name of the transformation you used.</p></li></ul><ul><li><p>Finally, if a transformation was needed, type in the exact name into
62this tool, rerun it, and verify that the raster was projected as you
63desired.</p></li></ul></td></tr><tr><td class="info">{NEAREST | BILINEAR | CUBIC}</td><td class="info" align="left"><p>The resampling algorithm to be used to project the original raster
64to a new coordinate system. The ArcGIS Project Raster tool is used to
65perform the projection and accepts the following values:</p><ul><li><p>NEAREST - nearest neighbor interpolation</p></li></ul><ul><li><p>BILINEAR - bilinear interpolation</p></li></ul><ul><li><p>CUBIC - cubic convolution</p></li></ul><p>You must specify one of these algorithms to project to a new
66coordinate system. An error will be raised if you specify a new
67coordinate system without selecting an algorithm.</p></td></tr><tr><td class="info">{projectedCellSize}</td><td class="info" align="left"><p>The cell size of the projected coordinate system. Although this
68parameter is optional, to receive the best results, the ArcGIS
69documentation recommends you always specify it when projecting to a
70new coordinate system.</p></td></tr><tr><td class="info">{registrationPoint}</td><td class="info" align="left"><p>The x and y coordinates (in the output space) used for pixel
71alignment.</p><p>This parameter is a new option introduced by ArcGIS 9.2. You must have
72ArcGIS 9.2 to use this parameter. It is ignored if you do not specify
73that the raster should be projected to a new coordinate system.</p></td></tr><tr><td class="info">{clippingDataset}</td><td class="info" align="left"><p>Existing feature class, raster, or other geographic dataset having
74the extent to which the raster should be clipped.</p><p>WARNING: If you use this tool from in an ArcGIS geoprocessing model
75and you select a dataset by clicking the folder icon and browsing to
76the dataset, your selection may mysteriously disappear from this text
77box after you close the tool. This is a bug in ArcGIS. To work around
78it, drag and drop the desired dataset into the model. This will create
79a layer in the model for that dataset. Then select that layer in this
80tool by clicking the drop-down box rather than clicking the folder
81icon. The selected layer should not disappear when you close the
82tool.</p></td></tr><tr><td class="info">{clippingRectangle}</td><td class="info" align="left"><p>Rectangle to which the raster should be clipped.</p><p>If a projected coordinate system was specified, the clipping is
83performed after the projection and the rectangle's coordinates should
84be specified in the new coordinate system. If no projected coordinate
85system was specified, the coordinates should be specified in the
86original coordinate system.</p><p>The ArcGIS Clip tool is used to perfom the clip. The clipping
87rectangle must be passed to this tool as a string of four numbers
88separated by spaces. The ArcGIS user interface automatically formats
89the string properly; when invoking this tool from the ArcGIS UI,
90you need not worry about the format. But when invoking it
91programmatically, take care to provide a properly-formatted string.
92The numbers are ordered LEFT, BOTTOM, RIGHT, TOP. For example, if the
93raster is in a geographic coordinate system, it may be clipped to 10
94W, 15 S, 20 E, and 25 N with the string:</p><dl><dt></dt><dd><p>10 15 20 25</p></dd></dl><p>Integers or decimal numbers may be provided.</p></td></tr><tr><td class="info">{mapAlgebraExpression}</td><td class="info" align="left"><p>Map algebra expression to execute on the raster.</p><p><b>WARNING:</b> The ArcGIS Geoprocessing Model Builder may randomly and
95silently delete the value of this parameter. This is a bug in ArcGIS.
96Before running a model that you have saved, open this tool and
97validate that the parameter value still exists.</p><p>The expression is executed after the converted raster is projected and
98clipped (if those options are specified). Use the case-sensitive
99string inputRaster to represent the raster that you now want to
100perform map algebra upon. For example, to convert the raster to an
101integer raster and add 1 to all of the cells, use this expression:</p><dl><dt></dt><dd><pre>int(inputRaster) + 1</pre></dd></dl><p>The string inputRaster is case-sensitive. Prior to executing the map
102algebra expression, the string is replaced with the path to a
103temporary raster that represents the raster being generated. The final
104expression must be less than 4000 characters long or ArcGIS will
105report an error.</p><p>The ArcGIS Single Output Map Algebra tool is used to execute the map
106algebra expression. You must have a license for the ArcGIS Spatial
107Analyst extension in order to perform map algebra.</p><p>Map algebra syntax can be very picky. Here are some tips that will
108help you succeed with this tool:</p><ul><li><p>Before using this tool, construct and test out your map algebra
109expression using the ArcGIS Single Output Map Algebra tool. Then
110paste the expression into this tool and edit it to use the
111inputRaster variable rather than the test value you used with Single
112Output Map Algebra.</p></li></ul><ul><li><p>If you do develop your expression directly in this tool, start with
113a very simple expression. Verify that it works properly, add a
114little to it, and verify again. Repeat this process until you have
115built up the complete expression.</p></li></ul><ul><li><p>Always separate mathematical operators from raster paths using
116spaces. In the example above, the / operator contains a space on
117either side. Follow this pattern. In some circumstances, ArcGIS will
118fail to process raster algebra expressions that do not separate
119raster paths from operators using spaces. The reported error message
120usually does not indicate that this is the problem, and tracking it
121down can be very frustrating.</p></li></ul></td></tr><tr><td class="info">{where}</td><td class="info" align="left"><p>SQL WHERE clause expression that specifies the subset of rows to
122process. If this parameter is not provided, all of the rows will be
123processed. If this parameter is provided but the underlying database
124does not support WHERE clauses, an error will be raised.</p><p>The exact syntax of this expression depends on the underlying
125database. ESRI recommends you reference fields using the following
126syntax:</p><ul><li><p>If you're querying ArcInfo coverages, shapefiles, INFO tables or
127dBASE tables (.dbf files), enclose field names in double quotes in
128the SQL expression: "MY_FIELD".</p></li></ul><ul><li><p>If you're querying Microsoft Access tables or personal
129geodatabase tables, enclose field names in square brackets:
130[MY_FIELD].</p></li></ul><ul><li><p>If you're querying ArcSDE geodatabase tables, an ArcIMS feature
131class, or an ArcIMS image service sublayer, don't enclose field
132names: MY_FIELD.</p></li></ul></td></tr><tr><td class="info">{orderBy;orderBy...}</td><td class="info" align="left"><p>Fields that will be used to sort the rows (i.e., the columns
133specified in the ORDER BY clause of a SQL SELECT statement). If no
134fields are provided, the rows will be sorted in the default order
135determined by the underlying database. If this parameter is provided
136but this computer is not running ArcGIS 9.2 or later or the underlying
137database does not support ORDER BY clauses, an error will be raised.</p><p>In addition to specifying the ORDER BY fields, you must also specify
138the sort direction for each field.</p></td></tr><tr><td class="info">{directions;directions...}</td><td class="info" align="left"><p>List of strings, either 'Ascending' or 'Descending', that specify
139the sort directions for the ORDER BY fields. If this parameter is
140provided but this computer is not running ArcGIS 9.2 or later or the
141underlying database does not support ORDER BY clauses, an error will
142be raised.</p></td></tr><tr><td class="info">{skipExisting}</td><td class="info" align="left"><p>If True, conversion will be skipped for feature classes that already exist.</p></td></tr><tr><td class="info">{basePath}</td><td class="info" align="left"><p>Base path to prepend to relative paths.</p><p>If a base path is provided, it will be prepended to any relative paths
143that are obtained from the fields that list the inputs (and outputs,
144if this tool has outputs). If a base path is not provided, the
145workspace containing the table will be prepended instead.</p></td></tr></tbody></table></div><p><h2><img width="11" height="11" border="0" src="sm_arrow_down.gif?format=raw" /> Scripting syntax</h2></p><div Class="expand" id="TEST">ArcGISRasterToPolygonOutlinesArcGISTable_GeoEco (table, inputRasterField, outputFeatureClassField, simplify, field, projectedCoordinateSystem, geographicTransformation, resamplingTechnique, projectedCellSize, registrationPoint, clippingDataset, clippingRectangle, mapAlgebraExpression, where, orderBy, directions, skipExisting, basePath) <br /><br /><b>Parameters</b><br /><table width="100%" border="0" cellpadding="5"><tbody><tr><th width="40%"><b>Expression</b></th><th width="60%"><b>Explanation</b></th></tr><tr><td class="info">Table (Required) </td><td class="info" align="left"><p>Table to query.</p></td></tr><tr><td class="info">Input raster field (Required) </td><td class="info" align="left"><p>Field containing the rasters to convert.</p><p>The rasters will be converted to polygon feature classes using the
146ArcGIS Raster to Polygon tool, and then to line features using the
147Feature to Line tool. The Raster to Polygon tool can only convert
148integer rasters to polygons. If the input rasters are floating-point
149rasters, you must use the Map Algebra Expression parameter to convert
150them to integer rasters.</p></td></tr><tr><td class="info">Output line feature class field (Required) </td><td class="info" align="left"><p>Field containing the output line feature classes.</p><p>One feature class will be created per raster. Missing directories the
151output paths will be created if they do not exist.</p></td></tr><tr><td class="info">Simplify polygons (Optional) </td><td class="info" align="left"><p>Determines if the output polygons will be smoothed into simpler
152shapes or conform to the input raster's cell edges.</p><ul><li><p>True - The polygons will be smoothed into simpler shapes. This is
153the default.</p></li></ul><ul><li><p>False - The polygons will conform to the input raster's cell edges.</p></li></ul></td></tr><tr><td class="info">Field (Optional) </td><td class="info" align="left"><p>The field used to assign values from the cells in the input raster
154to the lines in the output dataset. It can be an integer or a
155string field.</p></td></tr><tr><td class="info">Project to new coordinate system (Optional) </td><td class="info" align="left"><p>New coordinate system to project the raster to.</p><p>The raster may only be projected to a new coordinate system if the
156original projection is defined. An error will be raised if you specify
157a new coordinate system without defining the original coordinate
158system.</p><p>The ArcGIS Project Raster tool is used to perform the projection. The
159documentation for that tool recommends that you also specify a cell
160size for the new coordinate system.</p><p>I have noticed that for certain coordinate systems the ArcGIS 9.2
161Project Raster tool seems to clip the projected raster to an arbitrary
162extent that is too small. For example, when projecting a global MODIS
163Aqua 4 km chlorophyll image in geographic coordinates to
164Lambert_Azimuthal_Equal_Area with central meridian of -60 and latitude
165of origin of -63, the resulting image is clipped to show only
166one-quarter of the planet. This problem does not occur when Project
167Raster is invoked interactively from the ArcGIS user interface; it
168only occurs when the tool is invoked programmatically (the
169ProjectRaster_management method of the geoprocessor). Thus you may
170not see it when you use Project Raster yourself but it may happen when
171you use MGET tools that invoke Project Raster as part of their
172geoprocessing operations.</p><p>If you encounter this problem, you can work around it like this:</p><ul><li><p>First, run this tool without specifying a new coordinate system, to
173obtain the raster in the original coordinate system.</p></li></ul><ul><li><p>In ArcCatalog, use the Project Raster tool to project the raster to
174the new coordinate system. Verify that the entire raster is present,
175that it has not been clipped to an extent that is too small.</p></li></ul><ul><li><p>In ArcCatalog, look up the extent of the projected raster by
176right-clicking on it in the catalog tree, selecting Properties, and
177scrolling down to Extent.</p></li></ul><ul><li><p>Now, before running the MGET tool that projects the raster, set the
178Extent environment setting to the values you looked up. If you are
179invoking the MGET tool interactively from ArcCatalog or ArcMap,
180click the Environments button on the tool's dialog box, open General
181Settings, change the Extent drop-down to "As Specified Below", and
182type in the values you looked up. If you're invoking it from a
183geoprocessing model, right-click on the tool in the model, select
184Make Variable, From Environment, General Settings, Extent. This will
185place Extent as a variable in your model, attached to the MGET tool.
186Open the Extent variable, change it to "As Specified Below" and type
187in the values you looked up. If you're invoking the MGET tool
188programmatically, you must set the Extent property of the
189geoprocessor to the values you looked up. Please see the ArcGIS
190documentation for more information about this and Environment
191settings in general.</p></li></ul><ul><li><p>Run the MGET tool. The extent of the raster should now be the
192proper size.</p></li></ul></td></tr><tr><td class="info">Geographic transformation (Optional) </td><td class="info" align="left"><p>A transformation method used to convert between the original
193coordinate system and the new coordinate system.</p><p>This parameter is a new option introduced by ArcGIS 9.2. You must have
194ArcGIS 9.2 to use this parameter.</p><p>This parameter is only needed when you specify that the raster should
195be projected to a new coordinate system and that new system uses a
196different datum than the original coordinate system, or there is some
197other difference between the two coordinate systems that requires a
198transformation. To determine if a transformation is needed, I
199recommend the following procedure:</p><ul><li><p>First, run this tool without specifying a new coordinate system, to
200obtain the raster in the original coordinate system.</p></li></ul><ul><li><p>Next, use the ArcGIS 9.2 Project Raster tool on the raster to
201project it to the desired coordinate system. If a geographic
202transformation is needed, that tool will prompt you for one. Write
203down the exact name of the transformation you used.</p></li></ul><ul><li><p>Finally, if a transformation was needed, type in the exact name into
204this tool, rerun it, and verify that the raster was projected as you
205desired.</p></li></ul></td></tr><tr><td class="info">Projection resampling technique (Optional) </td><td class="info" align="left"><p>The resampling algorithm to be used to project the original raster
206to a new coordinate system. The ArcGIS Project Raster tool is used to
207perform the projection and accepts the following values:</p><ul><li><p>NEAREST - nearest neighbor interpolation</p></li></ul><ul><li><p>BILINEAR - bilinear interpolation</p></li></ul><ul><li><p>CUBIC - cubic convolution</p></li></ul><p>You must specify one of these algorithms to project to a new
208coordinate system. An error will be raised if you specify a new
209coordinate system without selecting an algorithm.</p></td></tr><tr><td class="info">Cell size for projected coordinate system (Optional) </td><td class="info" align="left"><p>The cell size of the projected coordinate system. Although this
210parameter is optional, to receive the best results, the ArcGIS
211documentation recommends you always specify it when projecting to a
212new coordinate system.</p></td></tr><tr><td class="info">Registration point for projected coordinate system (Optional) </td><td class="info" align="left"><p>The x and y coordinates (in the output space) used for pixel
213alignment.</p><p>This parameter is a new option introduced by ArcGIS 9.2. You must have
214ArcGIS 9.2 to use this parameter. It is ignored if you do not specify
215that the raster should be projected to a new coordinate system.</p></td></tr><tr><td class="info">Clip to extent of geographic dataset (Optional) </td><td class="info" align="left"><p>Existing feature class, raster, or other geographic dataset having
216the extent to which the raster should be clipped.</p><p>WARNING: If you use this tool from in an ArcGIS geoprocessing model
217and you select a dataset by clicking the folder icon and browsing to
218the dataset, your selection may mysteriously disappear from this text
219box after you close the tool. This is a bug in ArcGIS. To work around
220it, drag and drop the desired dataset into the model. This will create
221a layer in the model for that dataset. Then select that layer in this
222tool by clicking the drop-down box rather than clicking the folder
223icon. The selected layer should not disappear when you close the
224tool.</p></td></tr><tr><td class="info">Clip to rectangle (Optional) </td><td class="info" align="left"><p>Rectangle to which the raster should be clipped.</p><p>If a projected coordinate system was specified, the clipping is
225performed after the projection and the rectangle's coordinates should
226be specified in the new coordinate system. If no projected coordinate
227system was specified, the coordinates should be specified in the
228original coordinate system.</p><p>The ArcGIS Clip tool is used to perfom the clip. The clipping
229rectangle must be passed to this tool as a string of four numbers
230separated by spaces. The ArcGIS user interface automatically formats
231the string properly; when invoking this tool from the ArcGIS UI,
232you need not worry about the format. But when invoking it
233programmatically, take care to provide a properly-formatted string.
234The numbers are ordered LEFT, BOTTOM, RIGHT, TOP. For example, if the
235raster is in a geographic coordinate system, it may be clipped to 10
236W, 15 S, 20 E, and 25 N with the string:</p><dl><dt></dt><dd><p>10 15 20 25</p></dd></dl><p>Integers or decimal numbers may be provided.</p></td></tr><tr><td class="info">Execute map algebra expression (Optional) </td><td class="info" align="left"><p>Map algebra expression to execute on the raster.</p><p><b>WARNING:</b> The ArcGIS Geoprocessing Model Builder may randomly and
237silently delete the value of this parameter. This is a bug in ArcGIS.
238Before running a model that you have saved, open this tool and
239validate that the parameter value still exists.</p><p>The expression is executed after the converted raster is projected and
240clipped (if those options are specified). Use the case-sensitive
241string inputRaster to represent the raster that you now want to
242perform map algebra upon. For example, to convert the raster to an
243integer raster and add 1 to all of the cells, use this expression:</p><dl><dt></dt><dd><pre>int(inputRaster) + 1</pre></dd></dl><p>The string inputRaster is case-sensitive. Prior to executing the map
244algebra expression, the string is replaced with the path to a
245temporary raster that represents the raster being generated. The final
246expression must be less than 4000 characters long or ArcGIS will
247report an error.</p><p>The ArcGIS Single Output Map Algebra tool is used to execute the map
248algebra expression. You must have a license for the ArcGIS Spatial
249Analyst extension in order to perform map algebra.</p><p>Map algebra syntax can be very picky. Here are some tips that will
250help you succeed with this tool:</p><ul><li><p>Before using this tool, construct and test out your map algebra
251expression using the ArcGIS Single Output Map Algebra tool. Then
252paste the expression into this tool and edit it to use the
253inputRaster variable rather than the test value you used with Single
254Output Map Algebra.</p></li></ul><ul><li><p>If you do develop your expression directly in this tool, start with
255a very simple expression. Verify that it works properly, add a
256little to it, and verify again. Repeat this process until you have
257built up the complete expression.</p></li></ul><ul><li><p>Always separate mathematical operators from raster paths using
258spaces. In the example above, the / operator contains a space on
259either side. Follow this pattern. In some circumstances, ArcGIS will
260fail to process raster algebra expressions that do not separate
261raster paths from operators using spaces. The reported error message
262usually does not indicate that this is the problem, and tracking it
263down can be very frustrating.</p></li></ul></td></tr><tr><td class="info">Where clause (Optional) </td><td class="info" align="left"><p>SQL WHERE clause expression that specifies the subset of rows to
264process. If this parameter is not provided, all of the rows will be
265processed. If this parameter is provided but the underlying database
266does not support WHERE clauses, an error will be raised.</p><p>The exact syntax of this expression depends on the underlying
267database. ESRI recommends you reference fields using the following
268syntax:</p><ul><li><p>If you're querying ArcInfo coverages, shapefiles, INFO tables or
269dBASE tables (.dbf files), enclose field names in double quotes in
270the SQL expression: "MY_FIELD".</p></li></ul><ul><li><p>If you're querying Microsoft Access tables or personal
271geodatabase tables, enclose field names in square brackets:
272[MY_FIELD].</p></li></ul><ul><li><p>If you're querying ArcSDE geodatabase tables, an ArcIMS feature
273class, or an ArcIMS image service sublayer, don't enclose field
274names: MY_FIELD.</p></li></ul></td></tr><tr><td class="info">Order By fields (Optional) </td><td class="info" align="left"><p>Fields that will be used to sort the rows (i.e., the columns
275specified in the ORDER BY clause of a SQL SELECT statement). If no
276fields are provided, the rows will be sorted in the default order
277determined by the underlying database. If this parameter is provided
278but this computer is not running ArcGIS 9.2 or later or the underlying
279database does not support ORDER BY clauses, an error will be raised.</p><p>In addition to specifying the ORDER BY fields, you must also specify
280the sort direction for each field.</p></td></tr><tr><td class="info">Order By directions (Optional) </td><td class="info" align="left"><p>List of strings, either 'Ascending' or 'Descending', that specify
281the sort directions for the ORDER BY fields. If this parameter is
282provided but this computer is not running ArcGIS 9.2 or later or the
283underlying database does not support ORDER BY clauses, an error will
284be raised.</p></td></tr><tr><td class="info">Skip existing outputs (Optional) </td><td class="info" align="left"><p>If True, conversion will be skipped for feature classes that already exist.</p></td></tr><tr><td class="info">Base path (Optional) </td><td class="info" align="left"><p>Base path to prepend to relative paths.</p><p>If a base path is provided, it will be prepended to any relative paths
285that are obtained from the fields that list the inputs (and outputs,
286if this tool has outputs). If a base path is not provided, the
287workspace containing the table will be prepended instead.</p></td></tr></tbody></table></div></body></html>
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