topic Arcpy GetMessages in PythonWin in Python Questions

Arcpy GetMessages in PythonWin

JacobHorwitz1 — Tue, 28 Aug 2018 01:02:45 GMT

I'm a beginner to Python coding and now working on a basic script program, where I'm using both Print and arcpy.AddMessage/arcpy.AddError in a standalone script for ArcMap or in Pythonwin. However, I'm having issues with how I can do this for arcpy.GetMessages in PythonWin to find a traceback error.

I tried using:

msgs = arcpy.GetMessages(2)
print (msgs)
arcpy.AddMessage(msgs)

But couldn't get any traceback message. Is there a code that helps show the traceback error in Pythonwin?

Full Script below:

import arcpy
from arcpy import env
from arcpy.sa import *
arcpy.env.overwriteOutput = True

try:
# Sets the workspace evironment settings.
env.workspace = "E:/College/Penn State/GEOG 485/Lesson 1/Lesson1"

inRaster = "foxlake"
contourInterval = 25
baseContour = 0
outContours = "E:/College/Penn State/GEOG 485/Lesson 1/Lesson1/ContourFoxLake.shp"

arcpy.CheckOutExtension("Spatial")

arcpy.sa.Contour(inRaster, outContours, contourInterval, baseContour)

# Report a success message
print "Contour creation successful!"
arcpy.AddMessage("Contour creation successful!")

except:
    # Report an error message
    print "Failed to create the contour."
    arcpy.AddError("Failed to create the contour.")

    # Report any error messages that the Contour tool might have generated
    msgs = arcpy.GetMessages(2)
    print (msgs)
    arcpy.AddMessage(msgs)

Re: Arcpy GetMessages in PythonWin

DanPatterson_Retired — Tue, 28 Aug 2018 03:16:25 GMT

GetMessages—ArcPy Functions | ArcGIS Desktop

did you try just

msgs = arcpy.GetMessages() # get all

Re: Arcpy GetMessages in PythonWin

DanPatterson_Retired — Tue, 28 Aug 2018 03:30:28 GMT

As a note... if you take everything out of a try except block, you will get an error message which is largely the same as would be returned otherwise. I quite using try except blocks a long time ago... especially in cases where you only want to get the traceback messages rather than 'do' something else on failure.

From notes I made a long time agoo

Script variants Output

Script variants	Output
A very simple script, with an obvious error. `# version 1 print(something)`	( IDE dependent message.... ) File "Path_to_script\script_name.py", line 1, in <module> print(something) NameError: name 'something' is not defined
As above, but getting smarter. `# version 2 try: print(something) except: print("ooops")`	>>> ooops
Lets bring out the tools and see if that helps. `# version 3 import sys import traceback try: print(something) except: exc_traceback = sys.exc_info() print(traceback.print_exc())`	>>> Traceback (most recent call last): File "Path_to_script\script_name.py", line 5, in <module> print(something) NameError: name 'something' is not defined None

A very simple script, with an obvious error.

# version 1
print(something)

( IDE dependent message.... )

File "Path_to_script\script_name.py", line 1, in <module>

print(something)

NameError: name 'something' is not defined

As above, but getting smarter.

# version 2
try:
    print(something)
except:
    print("ooops")

>>> ooops

Lets bring out the tools and see if that helps.

# version 3
import sys
import traceback
try:
    print(something)
except:
    exc_traceback = sys.exc_info()
    print(traceback.print_exc())

>>> Traceback (most recent call last):

File "Path_to_script\script_name.py", line 5, in <module>

print(something)

NameError: name 'something' is not defined

None

You can draw your own conclusions which is the most useful