Walk

Resumen

Devuelve los nombres de datos del directorio y las estructuras de base de datos recorriendo el árbol de arriba abajo o de abajo arriba. Cada directorio o espacio de trabajo produce una triple tupla: ruta del directorio, nombres de directorio y nombres de archivo.

Debate

El módulo os contiene una función os.walk que se puede utilizar para recorrer un árbol de directorios y buscar datos. La función os.walk está basada en archivos y no reconoce el contenido de base de datos como clases de entidad de geodatabase, tablas ni rásteres. Para un mejor rendimiento, se recomienda utilizar os.walk para los formatos basados en archivos. La función arcpy.da.Walk se puede utilizar para catalogar datos.

Sintaxis

Walk (top, {topdown}, {onerror}, {followlinks}, {datatype}, {type})

Parámetro	Explicación	Tipo de datos
top	The top-level workspace that will be used.	String
topdown	If topdown is True or not specified, the tuple for a directory is generated before the tuple for any of its workspaces (workspaces are generated trom the top down). If topdown is False, the tuple for a workspace is generated after the tuple for all of its subworkspaces (workspaces are generated from the bottom up). When topdown is True, the dirnames list can be modified in place, and Walk will only recurse into the subworkspaces whose names remain in dirnames. This can be used to limit the search, impose a specific order of visiting, or inform Walk about directories the caller creates or renames before it resumes Walk again. Modifyingdirnames when topdown is False is ineffective, because in bottom-up mode, the workspaces indirnames are generated before dirpath is generated. (El valor predeterminado es True)	Boolean
onerror	Errors are ignored by default. The onerror function will be called with an OSError instance. This function can be used to report the error and continue with Walk or raise an exception to cancel. Nota: The file name is available as the filename attribute of the exception object. (El valor predeterminado es None)	Function
followlinks	By default, Walk does not visit connection files. Set followlinks to True to visit connection files. (El valor predeterminado es False)	Boolean
datatype	Specifies the data type that will be used to limit the results. Any—All data types are returned. This is equivalent to using None or skipping the argument. CadDrawing—CAD files (.dwg, .dxf, and .dgn) are returned. FeatureClass—Feature classes in a geodatabase and shapefiles (.shp) are returned. FeatureDataset—Feature datasets in a geodatabase are returned. GeometricNetwork—Geometric networks in a geodatabase are returned. LasDataset—LAS dataset files (.las and .lasd) are returned. Layer—Layer files (.lyrx) are returned. Locator—Locator files (.loc) are returned. Map— ArcGIS Pro projects (.aprx files), ArcGIS Pro map documents (.mapx files), and ArcMap documents (.mxd files) are returned. MosaicDataset—Mosaic datasets in a geodatabase are returned. NetworkDataset—Network datasets in a geodatabase are returned. RasterCatalog—Raster catalogs in a geodatabase are returned. RasterDataset—Raster datasets in a geodatabase or in a folder are returned. RelationshipClass—Relationship classes in a geodatabase are returned. RepresentationClass—Representation classes in a geodatabase are returned. Table—Tables in a geodatabase or folder and sheets in Excel workbooks are returned. Terrain—Terrain datasets are returned. Tin—TIN surfaces in a geodatabase are returned. Tool—Tools in a toolbox are returned. Topology—Topologies in a geodatabase are returned. Multiple data types are supported if they're entered as a list or tuple. for dirpath, dirnames, filenames in arcpy.da.Walk(workspace, datatype=['MosaicDataset', 'RasterDataset']): (El valor predeterminado es None)	String
type	Specifies whether feature and raster data types will be further limited by type. All—All types are returned. This is equivalent to using None or skipping the argument. Any—All types are returned. This is equivalent to using None or skipping the argument. Valid feature types are the following: Multipatch—Multipatch feature classes are returned. Multipoint—Multipoint feature classes are returned. Point—Point feature classes are returned. Polygon—Polygon feature classes are returned. Polyline—Polyline feature classes are returned. Valid raster types are the following: BIL— Esri Band Interleaved by Line file BIP— Esri Band Interleaved by Pixel file BMP— Bitmap graphic raster dataset format BSQ— Esri Band Sequential file DAT— ENVI DAT file GIF— Graphic Interchange Format for raster datasets GRID— Esri Grid raster dataset format IMG— ERDAS IMAGINE raster data format JP2— JPEG 2000 raster dataset format JPG— Joint Photographic Experts Group raster dataset format PNG— Portable Network Graphic raster dataset format TIF— Tag Image File Format for raster datasets Multiple data types are supported if they're entered as a list or tuple. for dirpath, dirnames, filenames in arcpy.da.Walk(workspace, datatype='FeatureClass', type=['Polygon', 'Polyline']): (El valor predeterminado es None)	String

Valor de retorno

Tipo de datos

Explicación

Generator

Genera una tupla de tres que incluye el espacio de trabajo, nombres de directorio y nombres de archivo. dirpath es la ruta al espacio de trabajo como una cadena de caracteres. dirnames es una lista de nombres de subdirectorios y otros espacios de trabajo de dirpath. filenames es una lista de nombres sin espacios de trabajo contenidos en dirpath. Nota: Los nombres de las listas incluyen solo el nombre base, no se incluyen componentes de la ruta. Para obtener de ruta completa (comenzando por la parte superior) de un archivo o directorio en dirpath, utilice os.path.join(dirpath, name).

Muestra de código

Ejemplo 1 de Walk

Use la función Walk para catalogar clases de entidad poligonal.

import arcpy
import os

workspace = "c:/data"
feature_classes = []

walk = arcpy.da.Walk(workspace, datatype="FeatureClass", type="Polygon")

for dirpath, dirnames, filenames in walk:
    for filename in filenames:
        feature_classes.append(os.path.join(dirpath, filename))

Ejemplo 2 de Walk

Use la función Walk para catalogar datos ráster. Se omitirán todos los rásteres de una carpeta llamada back_up.

import arcpy
import os

workspace = "c:/data"
rasters = []

walk = arcpy.da.Walk(workspace, topdown=True, datatype="RasterDataset")

for dirpath, dirnames, filenames in walk:
    # Disregard any folder named 'back_up' in creating list of rasters
    if "back_up" in dirnames:
        dirnames.remove('back_up')
    for filename in filenames:
        rasters.append(os.path.join(dirpath, filename))