topic Re: Python - how to select certain shapfiles in folder for projection in Python Questions

Python - how to select certain shapfiles in folder for projection

MarkWisniewski — Fri, 10 Apr 2015 00:29:24 GMT

Hi,

I am trying to create a python script with 3 parameters;

1) Dataset Folder which contains the shapefile datasets to be reprojected

2) Target Projection Dataset whose spatial reference will be used as specified projection in the reprojection

3) Projected Dataset Folder containing projected datasets

Re: Python - how to select certain shapfiles in folder for projection

DanPatterson_Retired — Fri, 10 Apr 2015 00:43:48 GMT

check the two formats in the help topic for spatial reference

dataset = "c:/data/landbase.gdb/Wetlands" spatial_ref = arcpy.Describe(dataset).spatialReference

Using a projection file (.prj)
sr = arcpy.SpatialReference("c:/coordsystems/NAD 1983.prj")

do note the subtle but difference in implementation and case in your case you are mixing the two.

Re: Python - how to select certain shapfiles in folder for projection

NeilAyres — Sat, 11 Dec 2021 10:31:24 GMT

This bit is not going to work -

for fc in fcList:
    if fc != spatialRef:

Consider what you are doing here.

fc is an text item from your list of features.

But spatialRef from the template describe object is a spatial reference object.

So they will never be equal.

Inside the loop you need to do another Describe of each fc, get the SR of that, then compare.

Re: Python - how to select certain shapfiles in folder for projection

MarkWisniewski — Fri, 10 Apr 2015 13:01:46 GMT

I have updated the script with the above suggestion, but it still doesn't work. I even tried template = filepathname, but that didn't work either. is there any other suggestion/comments? Thanks.

import arcpy

# Set Workspace

arcpy.env.workspace = arcpy.GetParameterAsText(0)

#Access shapefiles

fcList = arcpy.ListFeatureClasses()

try:

# Projection template

template = arcpy.GetParameterAsText(1)

# Output folder

outFolder = arcpy.GetParameterAsText(2)

# Get the spatial reference

spatialRef = arcpy.Describe(template).SpatialReference

#Loop through shapfiles in folder and reproject

for fc in fcList:

fcspatialRef = arcpy.Describe(fc).SpatialReference

if fcspatialRef != spatialRef:

arcpy.Project_management(fc, outFolder + "\\" + fc, spatialRef)

# Return any errors

except:

arcpy.AddMessage(arcpy.GetMessages ())

# Print shapefile list

for fc in fcList:

print fc

Re: Python - how to select certain shapfiles in folder for projection

NeilAyres — Fri, 10 Apr 2015 14:24:54 GMT

The block after try: should also be indented as well. How about telling us what errors you are getting instead saying "it doesn't work".

Not many clues there.

Re: Python - how to select certain shapfiles in folder for projection

DarrenWiens2 — Fri, 10 Apr 2015 17:54:52 GMT

Case matters in Python.

It is:

spatialRef = arcpy.Describe(template).spatialReference

Not:

spatialRef = arcpy.Describe(template).SpatialReference

Re: Python - how to select certain shapfiles in folder for projection

MarkWisniewski — Fri, 10 Apr 2015 21:19:57 GMT

Oh Sorry Neil. The code in the script is indented thanks to IDLE.

What is happening is all the shapefiles (8) are being reprojected, instead of the 6 shapefiles which have different projections to the template projection shapefile. 1 other file is in the same projection, so it shouldn't be projected.

Re: Python - how to select certain shapfiles in folder for projection

MarkWisniewski — Fri, 10 Apr 2015 21:30:53 GMT

Thanks Darren,

I changed "Spatial" to "spatial" and I also had to place .Name on the end and change "spatialRef" in Project tool to "template". The script is now working.

It's confusion because sometimes I see "Spatial" and "spatial"

Re: Python - how to select certain shapfiles in folder for projection

BlakeTerhune — Fri, 10 Apr 2015 23:47:32 GMT

Bad Joke Friday:

"You're extra Spatial!"