PyGeoprocessing库中允许对光栅值进行重分类的函数是什么？

Question

我正在尝试使用QGIS重分类按表对栅格值进行重分类，但它正在下降。我偶然发现了PyGeoprocessing库，显然它比R重分类函数快得多。但是，我在任何地方都找不到这个库的文档和教程。

谢谢你的帮助

Answer 1

PyGeoProcessing的重分类函数称为reclassify_raster，可以这样调用：

import pygeoprocessing
from osgeo import gdal

raster_path = 'the/path/to/your/input/raster.tif'

# You'll need to load your source and destination pixel values into a dictionary
# like this.  Oftentimes, this will be loaded in from a table.
reclassification_map = {
    1: 0.35
    2: 0.6
}


pygeoprocessing.reclassify_raster(
    (raster_path, 1),  # Use band 1
    reclassification_map,
    'reclassified.tif',
    gdal.GDT_Float32,  # You could use any gdal.GDT_* datatype, this example just uses Float32
    target_nodata=-1  # You could set the nodata value to whatever you wanted it to be
)

It's possible that the maintainers might release some API documentation, but until they do that, you can always just take a look at the function docstrings.  `reclassify_raster`, for example, is found in this file: https://github.com/natcap/pygeoprocessing/blob/main/src/pygeoprocessing/geoprocessing.py