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POLoading a feature class in a list using arcpy : strange behaviour of SearchCursor
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copied!<p>Using <code>arcpy</code>, my purpose is to stock a feature class in a list for further processing. Each row will be a dict of <code>{'field name': value}</code>, including geometry.</p> <p>The most pythonic way to achieve this task should be to use list comprehension :</p> <pre><code>fc = '/path/to/fc' fields = [f.name for f in arcpy.ListFields(fc)] # get field list features = [[row.getValue(f) for f in fields] for row in arcpy.SearchCursor(fc)] </code></pre> <p>This method works for data but geometries in the list are all the same (the last geometry retrieved in fc). <a href="https://stackoverflow.com/questions/10815149/appending-to-a-tuple-overwriting-previous-values">This behaviour of SearchCursor has already been commented on StackOverflow</a>.</p> <p>I tried another approach:</p> <pre><code>fc = '/path/to/fc' shape_field = arcpy.Describe(fc).shapeFieldName # load geometry in a list geom = arcpy.Geometry() feat = [{shape_field: f} for f in arcpy.CopyFeatures_management(fc, geom)] # slow # load data in a list fields = [f.name for f in arcpy.ListFields(fc)] data = [dict([(f, row.getValue(f)) for f in fields if f != shape_field]) for row in arcpy.SearchCursor(fc)] # slow # merge merge = zip(feat, data) merge = [dict([(k, v) for adict in line for (k, v) in adict.items()]) for line in merge] # sorry for that... </code></pre> <p>It works with my dataset but:</p> <ul> <li>It is slow.</li> <li>I'm not sure it's safe to assert that data and feat come in the same order.</li> </ul> <p>Any opinion on that ?</p>

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