making fishnet

[nedamohammadi1]

Hello Every body !

I want to make a fishnet for around 80 images (.tif), I want to call data from a path and make a fishnet for raws and columns 2*2.
who has idea?
Regards
Nedaaaa

[JakeSkinner]

You can use the Create Fishnet function to do this.  If all your rasters are in one directory, you can iterate through each raster using the List Rasters function.

[nedamohammadi1]

Thank you so much Jake!
It seems it was helpful, I had problem in the reading of data!I wrote this script:

#import arcpy and arcgisscripting
import arcgisscripting

gp = arcgisscripting.create(9.3)
gp.overwriteOutput = 1

import arcpy

# Set the current workspace
gp.env.workspace = r"X:\mohammadi\finalmunichGIS\clip0ffishnet9000\clip"
# Get and print a list of GRIDs from the workspace
rasters = arcpy.ListRasters("*", "TIF")
for raster in rasters:
    print(raster)
# input hard-coded but you can make it a script tool parameter to make it an interactive input.
#in_fc = r"X:\mohammadi\finalmunichGIS\clip0ffishnet9000\clip" # this polygon feature class has several polygons.

rows = gp.SearchCursor(rasters)
row = rows.Next()

while row:
    feat = row.raster
    ext = feat.extent
    orig = str(ext.xmin) + " " + str(ext.ymin)
    yaxis = str(ext.xmin) + " " + str(ext.ymin + 100.00)
    opp_corner = str(ext.xmax) + " " + str(ext.ymax)
    print orig, yaxis, opp_corner

outPath = r"X:\mohammadi\finalmunichGIS\fishnet4500\4500.shp"+ str(row.OBJECTID)


result = gp.CreateFishnet_management(outPath, orig, yaxis, "0", "0", "2", "2", opp_corner,"NO_LABELS","#","POLYGON")
  print(gp.GetMessages())

    row = rows.Next()

del row, rows

now error is in line 33: print(gp.GetMessages())
it is the first time I got such a problem?????

[JakeSkinner]

Try the following:

import arcpy
from arcpy import env
env.workspace = r"X:\mohammadi\finalmunichGIS\clip0ffishnet9000\clip"

lstRasters = arcpy.ListRasters("*", "TIF")
for raster in lstRasters:
    xmin = arcpy.Describe(raster).extent.XMin
    ymin = arcpy.Describe(raster).extent.YMin
    xmax = arcpy.Describe(raster).extent.XMax
    ymax = arcpy.Describe(raster).extent.YMax
    ymin2 = arcpy.Describe(raster).extent.YMin + 10
    arcpy.CreateFishnet_management("fishnet_" + raster[:-4] + ".shp", str(xmin) + " " + str(ymin), str(xmin) + " " + str(ymin2), "0","0","2","2", str(xmax) + " " + str(ymax), "NO_LABELS", "#","POLYGON")

print "Finished"

[nedamohammadi1]

Thank you so much, it worked!!:D

[nedamohammadi1]

Dear Jake Skinner !!
thank you so much for your help!!now I want to divide this fishnets by clip_management, I wrote this script:

# only import arcpy - don't use arcgisscripting/gp at 10.x
import arcpy
from arcpy import env


arcpy.env.overwriteOutput = True ## 1

env.workspace = r"X:\mohammadi\finalmunichGIS\munich.gdb"


# in_fc is your polygon feature class
in_fc = r"X:\mohammadi\finalmunichGIS\fishnet4500"

fcList = arcpy.ListFeatureClasses("","Polygon","")
for fc in fcList:
    lyrFC = "lyrFC"

    # in_fc is your polygon feature class
    in_fc = fc

    # in_tif is your input
    in_raster = r"X:\mohammadi\finalmunichGIS\Testdatenoriginaldata\munich_subset.tif"

    # output location
    outPath = r"X:\mohammadi\finalmunichGIS\lastclip"

    arcpy.MakeFeatureLayer_management(in_fc,lyrFC)

    # get list of object ids
    objIDs = []
    objIDField = arcpy.Describe(lyrFC).OIDFieldName
    rows = arcpy.SearchCursor(lyrFC)
    row = rows.next()

    while row:
        objIDs.append(row.getValue(objIDField))
        row = rows.next()

    del row, rows

    # temp polygons
    copyFC = r"X:\mohammadi\finalmunichGIS\test.gdb\fc_parent1_1c"

    # one by one clip raster to polygons
    arcpy.env.workspace= outPath
    for objID in objIDs:
        where = "{0} = {1}".format(objIDField,objID)
        arcpy.SelectLayerByAttribute_management(lyrFC,"NEW_SELECTION",where)
        arcpy.CopyFeatures_management(lyrFC,copyFC)
        ext = arcpy.Describe(copyFC).Extent
        extString = "{0} {1} {2} {3}".format(ext.xmin, ext.ymin, ext.xmax, ext.ymax)
        out_raster = "{0}_clip{1}.tif".format(in_fc, objID)
        arcpy.Clip_management(in_raster, extString, out_raster, copyFC)
        print arcpy.GetMessages(0)

    arcpy.Delete_management(copyFC)

it works but it makes clip likes as before for me it means whole of fishnet not four clips of every fishnet!!!
what is your sugestion?
thanks
neda

[nedamohammadi1]

Dear Jake!

I need to make clip from that fishnet it almost work , the only problem is error 000732:

# only import arcpy - don't use arcgisscripting/gp at 10.x
import arcpy
from arcpy import env


arcpy.env.overwriteOutput = True ## 1

env.workspace = r"X:\mohammadi\finalmunichGIS\fishnet4500\fishnet4500.gdb"


# in_fc is your polygon feature class
#in_fc = r"X:\mohammadi\finalmunichGIS\fishnet4500"

fcList = arcpy.ListFeatureClasses("","Polygon","")
for fc in fcList:
    lyrFC = "lyrFC"

    # in_fc is your polygon feature class
    in_fc = fc

    # in_tif is your input
    in_raster = r"X:\mohammadi\finalmunichGIS\Testdatenoriginaldata\munich_subset.tif"

    # output location
    outPath = r"X:\mohammadi\finalmunichGIS\lastclip"

    arcpy.MakeFeatureLayer_management(in_fc,lyrFC)

    # get list of object ids
    objIDs = []
    objIDField = arcpy.Describe(lyrFC).OIDFieldName
    rows = arcpy.SearchCursor(lyrFC)
    row = rows.next()

    while row:
        objIDs.append(row.getValue(objIDField))
        row = rows.next()

    del row, rows

    # temp polygons
    copyFC = r"X:\mohammadi\finalmunichGIS\test.gdb\test"

    # one by one clip raster to polygons
    arcpy.env.workspace= outPath
    for objID in objIDs:
        where = "{1} = {0}".format(objIDField,objID)
        arcpy.SelectLayerByAttribute_management(lyrFC,"NEW_SELECTION",where)
        arcpy.CopyFeatures_management(lyrFC,copyFC)
        ext = arcpy.Describe(copyFC).Extent
        extString = "{0} {1} {2} {3}".format(ext.xmin, ext.ymin, ext.xmax, ext.ymax)
        out_raster = "{0}_clip{1}.tif".format(in_fc, objID)
        arcpy.Clip_management(in_raster, extString, out_raster, copyFC)
        print arcpy.GetMessages(0)

    arcpy.Delete_management(copyFC)

because of the name of clips , sometimes they are same so it makes problem , so I must change last part of script I mean loop !!
what do you sugest ?I mean the name of clips must not be 1,2,3,4 sth like as a, b, c , but I don,t know how to manage that .I am so new in python:)

[JakeSkinner]

Are you trying to clip the fishnet polygon feature class by a directory of rasters?

[nedamohammadi1]

Yes I am going to do that, because my clips must be rasters or TIF , I want to use them in fragstats

[nedamohammadi1]

I must solve the problem in last part , Imean for the loop of :

for objID in objIDs:
        where = "{1} = {0}".format(objIDField,objID)
        arcpy.SelectLayerByAttribute_management(lyrFC,"NEW_SELECTION",where)
        arcpy.CopyFeatures_management(lyrFC,copyFC)
        ext = arcpy.Describe(copyFC).Extent
        extString = "{0} {1} {2} {3}".format(ext.xmin, ext.ymin, ext.xmax, ext.ymax)
        out_raster = "{0}_clip{1}.tif".format(in_fc, objID)
        arcpy.Clip_management(in_raster, extString, out_raster, copyFC)
        print arcpy.GetMessages(0)

because the name of clips are like as this for example:fishnet_fc_parent1_10_clip1_clip1
so 1, 2 , 3, 4 makes problem , because some of them are same.error 000732 and error 000725
😞