SubsetBands

摘要

根据所选的波段子集创建多维栅格或高光谱栅格的子集栅格对象。 输出保持与输入相同的波段顺序。

说明

栅格对象所引用的栅格数据集是临时性的。 要将其设置为永久，可以调用栅格对象的 save 方法。

有关此函数工作原理的详细信息，请参阅子集化波段栅格函数。

语法

SubsetBands (raster, {method}, {bands}, {missing_band_action}, {exclude_bad_bands})

参数	说明	数据类型
raster	The input hyperspectral or multidimensional raster.	Raster
method	Specifies the method that will be used to extract and create the subset of the bands. BY_NAMES—Band names will be used to identify and create the subset of bands for extraction. BY_WAVELENGTHS—Band wavelengths on the electromagnetic spectrum will be used to identify and create the subset of bands for extraction. BY_IDS—The band designation or sequence number will be used to identify and create the subset of bands for extraction. (默认值为 BY_IDS)	String
bands	The bands that will be extracted based on the specified method argument option. The following are examples: Using the BY_NAMES option for the method argument, specify 'band_15 band_13 band_14'. Using the BY_WAVELENGTHS option for the method argument, specify '400-700 900'. Using the BY_IDS option for the method argument, specify '100 105 110 120-130'. Values will be minus by 1 for a 0-based index. The bands argument is used to specify the bands to extract and depends on the method option specified. The bands are entered as a space-delimited list and can be specified as ranges of bands. For example, when specifying a subset using the BY_IDS option for the method parameter, a value of 20-50 60-100 200 will extract band IDs between (inclusive) 20 and 50, 60 and 100, and a band with an ID of 200. When specifying the bands parameter value using the BY_WAVELENGTHS option for the method argument, all bands within the wavelength range will be extracted. When specifying bands by wavelength, the units—such as microns or nanometers—are the same as the input units. Subsets using the BY_NAMES option must be a list of individual names delimited by a space, such as band_1 band_2 band_3. Range is not supported for the BY_NAMES option. (默认值为 None)	String
missing_band_action	Specifies the action that will occur when a band from the bands argument value is not available. BestMatch—The best available band in place of the missing band based on wavelength will be used. Fail—If the input dataset is missing any band specified in the bands argument, the function will fail. (默认值为 BestMatch)	String
exclude_bad_bands	Specifies whether bands that have been flagged as bad will be excluded. True—Bad bands will be excluded. False—Bad bands will not be excluded. (默认值为 False)	Boolean

返回值

数据类型	说明
Raster	输出子集栅格。

代码示例

SubsetBands 示例 1

此示例使用 BY_IDS 选项从输入栅格中提取波段。

extracted_bands = arcpy.ia.SubsetBands(raster=img_lyr, method="BY_IDS", bands="100 105 110 120-130")

SubsetBands 示例 2

此示例使用 BY_NAMES 选项从输入栅格中提取波段。

extracted_bands = arcpy.ia.SubsetBands(raster=img_lyr, method="BY_NAMES", bands="band_15 band_13 band_14")

SubsetBands 示例 3

此示例使用 BY_WAVELENGTHS 选项从输入栅格中提取波段。

extracted_bands = arcpy.ia.SubsetBands(raster=img_lyr, method="BY_WAVELENGTHS", bands="400-700 900")