 |  |  | GeoEco Python Reference |  |  |  |
| | | GeoEco Python Reference | | | |
Converts a Scientific Data Set (SDS) in each HDF file in a table to an ArcGIS raster.
| Class: | HDF |
| Intended use: | Recommended for external callers |
| COM: | Not exposed by a COM class |
| ArcGIS: | Not exposed as an ArcGIS geoprocessing tool |
| Method type: | Classmethod |
| HDF.ToArcGISRasterTable( | connection, table, inputFileField, outputRasterField, sdsName, xLowerLeftCorner, yLowerLeftCorner, cellSize[, nodataValue[, transpose[, mirror[, flip[, swapHemispheres[, coordinateSystem[, projectedCoordinateSystem[, geographicTransformation[, resamplingTechnique[, projectedCellSize[, registrationPoint[, clippingRectangle[, mapAlgebraExpression[, buildPyramids[, where[, orderBy[, directions[, skipExisting[, overwriteExisting[, basePath]]]]]]]]]]]]]]]]]]]]) |
| Python type: | GeoEco.DatabaseAccess.DatabaseConnection |
Connection opened to the database that contains the table.
| Python type: | unicode |
| Minimum length: | 1 |
Name of the table to query.
| Python type: | unicode |
| Minimum length: | 1 |
Field containing the paths of the input HDF files.
At the time this tool was written, two major versions of HDF were under continuing development: HDF, which was at release 4.2r1, and HDF5, which was at release 5-1.6.5. This tool can process HDF files but not HDF5 files. It can also process HDF-EOS, a specialized version of HDF, but not HDF5-EOS.
For more information on HDF formats, please see http://www.hdfgroup.org.
If you provide compressed files in a supported compression format, they will be automatically decompressed. If files are compressed in an archive format (e.g. .zip or .tar), each archive must contain exactly one file, which must not be in a subdirectory.
| Python type: | unicode |
| Minimum length: | 1 |
Field containing the output rasters to create.
| Python type: | unicode |
| Minimum length: | 1 |
Name of a Scientific Data Set (SDS) in the HDF file.
If you do not know the name of the SDS, provide your best guess. If an SDS does not exist with that name, a ValueError will be raised. The error message will list the names of all SDSes present in the input file. Select one of these names try again.
You can also use the Extract HDF Header tool to dump the HDF header to a text file. In this file, each SDS will be called a "variable". You can find their names by searching the file for "Variable Name =". For example, the excerpt below from MODIS SST data lists two variables, l3m_data and l3m_qual:
Variable Name = l3m_data
Index = 0
Type= 16-bit unsigned integer
Ref. = 2
Rank = 2
Number of attributes = 4
Dim0: Name=fakeDim0
Size = 4320
Scale Type = number-type not set
Number of attributes = 0
Dim1: Name=fakeDim1
Size = 8640
Scale Type = number-type not set
Number of attributes = 0
Attr0: Name = Scaling
Type = 8-bit signed char
Count= 7
Value = linear\\000
Attr1: Name = Scaling Equation
Type = 8-bit signed char
Count= 47
Value = (Slope*l3m_data) + Intercept = Parameter
value\\000
Attr2: Name = Slope
Type = 32-bit floating point
Count= 1
Value = 0.000717
Attr3: Name = Intercept
Type = 32-bit floating point
Count= 1
Value = -2.000000
Variable Name = l3m_qual
Index = 1
Type= 8-bit unsigned integer
Ref. = 4
Rank = 2
Number of attributes = 1
Dim0: Name=fakeDim2
Size = 4320
Scale Type = number-type not set
Number of attributes = 0
Dim1: Name=fakeDim3
Size = 8640
Scale Type = number-type not set
Number of attributes = 0
Attr0: Name = valid_range
Type = 32-bit signed integer
Count= 2
Value = 0 2This tool extracts the HDF SDS to an ArcInfo ASCII Grid and converts it to a raster using the ArcGIS ASCII to Raster geoprocessing tool. That tool and the ArcGIS raster format have several limitations that constrain the kinds of SDSes that may be successfully converted to ArcGIS raster format.
SDSes that use the float or double data type must not contain "infinity" (INF) or "not a number" (NAN) values. A ValueError will be raised if these values are discovered.
The ArcGIS raster format supports the 32-bit float data type but not the 64-bit double data type. If you supply an SDS with the double data type, it will be converted to a 32-bit float raster using the ArcGIS ASCII to Raster geoprocessing tool. The tool's behavior in this situation is not documented. In ArcGIS 9.1 it appears to be:
The ArcGIS 9.1 ASCII to Raster tool also exhibits some quirks when converting integer rasters:
| Python type: | float |
X coordinate of the lower-left corner of the raster.
The coordinate is for the corner of the lower-left cell, not the center of that cell. For example, if the raster is a geographic projection of the entire Earth, the coordinate of the lower left corner would be -180.0, corresponding to a longitude of 180 degrees West.
| Python type: | float |
Y coordinate of the lower-left corner of the raster.
The coordinate is for the corner of the lower-left cell, not the center of that cell. For example, if the raster is a geographic projection of the entire Earth, the coordinate of the lower left corner would be -90.0, corresponding to a latitude of 90 degrees South.
| Python type: | float |
Size of each raster cell.
For example, if the raster is a geographic projection of the entire Earth, with 720 columns and 360 rows, it would have a cell size of 0.5, corresponding to 1/2 of a geographic degree.
The underlying data format requires the cells be square. It is not possible to specify a cell size for each dimension.
| Python type: | float or None |
| Default value: | None |
Value that indicates a cell has no data.
| Python type: | bool |
| Default value: | False |
If True, the image will be transposed (flipped about the diagonal axis) prior to conversion. Use this option to fix an image that has the east/west axis going up and down instead of left and right.
| Python type: | bool |
| Default value: | False |
If True, the image will be flipped about the vertical axis prior to conversion. Use this option to fix an image that is the "mirror image" of what it is supposed to be.
| Python type: | bool |
| Default value: | False |
If True, the image will be flipped about the horizontal axis prior to conversion. Use this option to fix an image that is upside-down.
| Python type: | bool |
| Default value: | False |
If True, the east and west hemispheres of the image will be swapped. Use this option to change the orientation of a global image from a 0 to 360 orientation centered on the Pacific ocean to a -180 to +180 orientation centered on the Atlantic ocean, or visa versa.
| Python type: | unicode or None |
| Default value: | None |
| Minimum length: | 1 |
Coordinate system to define for the raster.
If a value is not provided, the coordinate system of the raster will remain undefined.
| Python type: | unicode or None |
| Default value: | None |
| Minimum length: | 1 |
New coordinate system to project the raster to.
The raster may only be projected to a new coordinate system if the original projection is defined. An error will be raised if you specify a new coordinate system without defining the original coordinate system.
The ArcGIS Project Raster tool is used to perform the projection. The documentation for that tool recommends that you also specify a cell size for the new coordinate system.
I have noticed that for certain coordinate systems the ArcGIS 9.2 Project Raster tool seems to clip the projected raster to an arbitrary extent that is too small. For example, when projecting a global MODIS Aqua 4 km chlorophyll image in geographic coordinates to Lambert_Azimuthal_Equal_Area with central meridian of -60 and latitude of origin of -63, the resulting image is clipped to show only one-quarter of the planet. This problem does not occur when Project Raster is invoked interactively from the ArcGIS user interface; it only occurs when the tool is invoked programmatically (the ProjectRaster_management method of the geoprocessor). Thus you may not see it when you use Project Raster yourself but it may happen when you use MGET tools that invoke Project Raster as part of their geoprocessing operations.
If you encounter this problem, you can work around it like this:
| Python type: | unicode or None |
| Default value: | None |
| Minimum length: | 1 |
A transformation method used to convert between the original coordinate system and the new coordinate system.
This parameter is a new option introduced by ArcGIS 9.2. You must have ArcGIS 9.2 to use this parameter.
This parameter is only needed when you specify that the raster should be projected to a new coordinate system and that new system uses a different datum than the original coordinate system, or there is some other difference between the two coordinate systems that requires a transformation. To determine if a transformation is needed, I recommend the following procedure:
| Python type: | unicode or None |
| Default value: | None |
| Allowed values: | u'NEAREST', u'BILINEAR', u'CUBIC' |
The resampling algorithm to be used to project the original raster to a new coordinate system. The ArcGIS Project Raster tool is used to perform the projection and accepts the following values:
You must specify one of these algorithms to project to a new coordinate system. An error will be raised if you specify a new coordinate system without selecting an algorithm.
| Python type: | float or None |
| Default value: | None |
The cell size of the projected coordinate system. Although this parameter is optional, to receive the best results, the ArcGIS documentation recommends you always specify it when projecting to a new coordinate system.
| Python type: | unicode or None |
| Default value: | None |
| Minimum length: | 1 |
| Must match regular expression: | ([-+]?[0-9]*\.?[0-9]+([eE][-+]?[0-9]+)?)\s+([-+]?[0-9]*\.?[0-9]+([eE][-+]?[0-9]+)?) |
The x and y coordinates (in the output space) used for pixel alignment.
This parameter is a new option introduced by ArcGIS 9.2. You must have ArcGIS 9.2 to use this parameter. It is ignored if you do not specify that the raster should be projected to a new coordinate system.
| Python type: | unicode or None |
| Default value: | None |
| Minimum length: | 1 |
| Must match regular expression: | ([-+]?[0-9]*\.?[0-9]+([eE][-+]?[0-9]+)?)\s+([-+]?[0-9]*\.?[0-9]+([eE][-+]?[0-9]+)?)\s+([-+]?[0-9]*\.?[0-9]+([eE][-+]?[0-9]+)?)\s+([-+]?[0-9]*\.?[0-9]+([eE][-+]?[0-9]+)?) |
Rectangle to which the raster should be clipped.
If a projected coordinate system was specified, the clipping is performed after the projection and the rectangle's coordinates should be specified in the new coordinate system. If no projected coordinate system was specified, the coordinates should be specified in the original coordinate system.
The ArcGIS Clip tool is used to perfom the clip. The clipping rectangle must be passed to this tool as a string of four numbers separated by spaces. The ArcGIS user interface automatically formats the string properly; when invoking this tool from the ArcGIS UI, you need not worry about the format. But when invoking it programmatically, take care to provide a properly-formatted string. The numbers are ordered LEFT, BOTTOM, RIGHT, TOP. For example, if the raster is in a geographic coordinate system, it may be clipped to 10 W, 15 S, 20 E, and 25 N with the string:
10 15 20 25
Integers or decimal numbers may be provided.
| Python type: | unicode or None |
| Default value: | None |
| Minimum length: | 1 |
| Maximum length: | 4000 |
Map algebra expression to execute on the raster.
WARNING: The ArcGIS Geoprocessing Model Builder may randomly and silently delete the value of this parameter. This is a bug in ArcGIS. Before running a model that you have saved, open this tool and validate that the parameter value still exists.
The expression is executed after the converted raster is projected and clipped (if those options are specified). Use the case-sensitive string inputRaster to represent the raster that you now want to perform map algebra upon. For example, to convert the raster to an integer raster and add 1 to all of the cells, use this expression:
int(inputRaster) + 1
The string inputRaster is case-sensitive. Prior to executing the map algebra expression, the string is replaced with the path to a temporary raster that represents the raster being generated. The final expression must be less than 4000 characters long or ArcGIS will report an error.
The ArcGIS Single Output Map Algebra tool is used to execute the map algebra expression. You must have a license for the ArcGIS Spatial Analyst extension in order to perform map algebra.
Map algebra syntax can be very picky. Here are some tips that will help you succeed with this tool:
| Python type: | bool |
| Default value: | False |
If True, pyramids will be built for the raster, which will improve its display speed in the ArcGIS user interface.
| Python type: | unicode or None |
| Default value: | None |
| Minimum length: | 1 |
SQL WHERE clause expression that specifies the subset of rows to process. If this parameter is not provided, all of the rows will be processed. If this parameter is provided but the underlying database does not support WHERE clauses, an error will be raised.
The exact syntax of this expression depends on the underlying database and the type of connection used to access it. If you are using the ArcGIS geoprocessor to access the database, ESRI recommends you reference fields using the following syntax:
| Python type: | list of unicode, or None |
| Default value: | None |
| Minimum length: | 0 |
Fields that will be used to sort the rows (i.e., the columns specified in the ORDER BY clause of a SQL SELECT statement). If no fields are provided, the rows will be sorted in the default order determined by the underlying database. If this parameter is provided but the underlying database does not support ORDER BY clauses, an error will be raised.
In addition to specifying the ORDER BY fields, you must also specify the sort direction for each field.
| Python type: | list of unicode, or None |
| Default value: | None |
| Minimum length: | 0 |
List of strings, either 'Ascending' or 'Descending', that specify the sort directions for the ORDER BY fields. If this parameter is provided but the underlying database does not support ORDER BY clauses, an error will be raised.
| Python type: | bool |
| Default value: | False |
If True, processing will be skipped for rasters that already exist.
| Python type: | bool |
| Default value: | False |
If True and skipExisting is False, existing rasters will be overwritten.
| Python type: | unicode or None |
| Default value: | None |
| Minimum length: | 1 |
| Maximum length: | 255 |
| Must exist: | No |
Base path to prepend to relative paths.
If any of the input paths (or output paths, if this method has outputs) obtained from the table are relative paths, they will be converted to absolute paths prior to processing, as follows:
| | | GeoEco Python Reference | | | |