topic Re: Dumb question - can I write standalone python script to run without arcgis? in Geoprocessing Questions

Dumb question - can I write standalone python script to run without arcgis?

jimparsons — Wed, 19 May 2010 06:54:30 GMT

I need to open a raster, thin it, and save it. Can I do that in a script outside of arcgis, or does arcgis need to be running for the script to work? I have it installed on the system, so it would obviously be running on my computer.

Sorry this question is really simple. I don't really understand how to run a script outside of arcgis...or even if it's possible. I'm hoping someone will say yes or no! Thanks

Re: Dumb question - can I write standalone python script to run without arcgis?

ToreBorvik — Wed, 19 May 2010 08:01:17 GMT

nope. You do not need to have arcgis open, you can call geoprocessing from within the script.

Re: Dumb question - can I write standalone python script to run without arcgis?

KoenVolleberg — Wed, 19 May 2010 11:03:48 GMT

I believe it is possible. Just write a Python script as if it were run from within ArcGIS.
Run it from within a dos-prompt: <name_script.py> <param1> <param2>...

Works for me, so I think it should work for you as well. But only just as long you have ArcGIS installed.
Cheers, Koen

Re: Dumb question - can I write standalone python script to run without arcgis?

RDHarles — Wed, 19 May 2010 16:59:46 GMT

Absolutely, I run all my python scripts without ArcMap open, from a command line.

Re: Dumb question - can I write standalone python script to run without arcgis?

JoelCalhoun — Wed, 19 May 2010 18:42:33 GMT

Another way to run them outside of ArcGIS or the command prompt is just to open them in an IDE (python editing program) and run them from there.

Re: Dumb question - can I write standalone python script to run without arcgis?

jimparsons — Wed, 19 May 2010 21:30:39 GMT

Thank you. I find the model builder great for building, but not great for naming the files that inevitably crop up. I use the scratch space thing, but I think I could do a better job programmatically creating new folders based on time and date. I'm pretty confident I can do that in python...

Re: Dumb question - can I write standalone python script to run without arcgis?

jimparsons — Wed, 19 May 2010 22:38:25 GMT

Here's another kinda dumb question. How hard would it be to write a script to:

do
zoom to layer for each raster in document
file -> export map based on current extent
loop for each raster in doc

With python it's easy to access the toolbox, but how would we access a) the zoom to layer command, and b) the file export map tool, which is a very handy way to effectively merge lots of 24 bit color rasters simply by opening them all and exporting the overall map at great resolution.

In this instance I want to zoom to layer of each one so I can export them as a geotiff, not as tif + tfw as they are at the moment.

I have no idea how difficult the above job is. Can anyone tell me? Thanks

Re: Dumb question - can I write standalone python script to run without arcgis?

ToreBorvik — Thu, 20 May 2010 08:04:14 GMT

Not easy at least. I've not succeeded in making arcmap zoom around in a document from a script. But I'm no script pro..

Re: Dumb question - can I write standalone python script to run without arcgis?

jimparsons — Thu, 20 May 2010 08:59:20 GMT

Life would be much easier if we could record batch macros like in Photoshop.....without having to write arcobjects script.

Re: Dumb question - can I write standalone python script to run without arcgis?

JoelCalhoun — Mon, 24 May 2010 19:00:14 GMT

ArcGIS 10 will include arcpy.mapping. It will allow for the maipulation of layer files, aspects of the layout, map
automation, and export with Python. The added functionality might enable you to do what you want.

Re: Dumb question - can I write standalone python script to run without arcgis?

BartKowalski — Tue, 02 Nov 2010 20:43:36 GMT

"With python it's easy to access the toolbox, but how would we access a) the zoom to layer command, and b) the file export map tool, which is a very handy way to effectively merge lots of 24 bit color rasters simply by opening them all and exporting the overall map at great resolution."

Hi Jim,

I was wandering if you were successful in writing that python script.I am trying to do something similar. I'd apprecaite you reply, thanks.

Re: Dumb question - can I write standalone python script to run without arcgis?

DanPatterson_Retired — Sat, 11 Dec 2021 15:08:58 GMT

It just needs to be present on the computer. It need not be running but arcpy needs to be imported which means it must be on the computer. gp.Addmessage statements need to be replaced with print statements. The following is an example

'''
CreatePolyDemo.py

Demonstrates calculating various properties for polygons

'''
import arcpy
pnt = arcpy.Point()

triangle = [[0,0],[0,1],[1,0]]
square = [[0,0],[0,1],[1,1],[1,0]]
rectangle = [[0,0],[0,1],[2,1],[2,0]]
polygons = [triangle, square, rectangle]
labels = ["Triangle", "Square", "Rectangle"]
array = arcpy.Array()
polys = []
for i in range(len(polygons)):
  a_poly = polygons
  print "\n", labels," Coordinates: ", a_poly
  for pair in a_poly:
    pnt.X = pair[0]
    pnt.Y = pair[1]
    array.add(pnt)
    print " X %20.16f  Y %20.16f" % (pnt.X, pnt.Y)
  array.add(array.getObject(0))
  poly = arcpy.Polygon(array)
  print "Polygon properties:"
  print " area %20.16f\n length %s" % (poly.area, poly.length)
  print " centroid %s\n true centroid %s " % (poly.centroid, poly.trueCentroid) 
  print " first point %s\n last point %s " % (poly.firstPoint, poly.lastPoint)
  print " extent %s " % (poly.extent)
  print " hull %s\n " % (poly.hullRectangle)
  array.removeAll()
  polys.append(poly)

Re: Dumb question - can I write standalone python script to run without arcgis?

ChrisMathers — Wed, 03 Nov 2010 12:05:17 GMT

Bart, Those are methods of the arcpy.mapping class. Its actually very easy once you read over the docs.

http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Geoprocessing_scripts_for_map_document_management_and_output/00s300000032000000/

Re: Dumb question - can I write standalone python script to run without arcgis?

FrankPerks — Sat, 11 Dec 2021 15:09:00 GMT

'''
CreatePolyDemo.py

Demonstrates calculating various properties for polygons

'''
import arcpy
pnt = arcpy.Point()

triangle = [[0,0],[0,1],[1,0]]
square = [[0,0],[0,1],[1,1],[1,0]]
rectangle = [[0,0],[0,1],[2,1],[2,0]]
polygons = [triangle, square, rectangle]
labels = ["Triangle", "Square", "Rectangle"]
array = arcpy.Array()
polys = []
for i in range(len(polygons)):
  a_poly = polygons
  print "\n", labels," Coordinates: ", a_poly
  for pair in a_poly:
    pnt.X = pair[0]
    pnt.Y = pair[1]
    array.add(pnt)
    print " X %20.16f  Y %20.16f" % (pnt.X, pnt.Y)
  array.add(array.getObject(0))
  poly = arcpy.Polygon(array)
  print "Polygon properties:"
  print " area %20.16f\n length %s" % (poly.area, poly.length)
  print " centroid %s\n true centroid %s " % (poly.centroid, poly.trueCentroid) 
  print " first point %s\n last point %s " % (poly.firstPoint, poly.lastPoint)
  print " extent %s " % (poly.extent)
  print " hull %s\n " % (poly.hullRectangle)
  array.removeAll()
  polys.append(poly)

gp.addmessage() will just print to console if the script was not called from ArcMap

Re: Dumb question - can I write standalone python script to run without arcgis?

DanPatterson_Retired — Wed, 03 Nov 2010 19:17:26 GMT

Frank...unfortunately it doesn't print to other IDE's output...don't use console...too dark and gloomy and reminds me of the old DOS days

Re: Dumb question - can I write standalone python script to run without arcgis?

LoganPugh — Sat, 11 Dec 2021 15:09:03 GMT

Frank...unfortunately it doesn't print to other IDE's output...don't use console...too dark and gloomy and reminds me of the old DOS days

It's for that reason that I wrote my own message(), warning() and error() methods. In addition to logging to a text file, it's exactly 3 places that I need to change if I need print statements or not, not dozens of lines littered throughout the script.

Most of the time I don't need print messages, but if I'm debugging in PyScripter or PythonWin (but not winpdb which runs the script in a separate console window from the GUI), I'll uncomment my print statement in each of the 3 methods.

# Helper methods for writing messages, warnings and errors to the geoprocessor as well as a logfile
# By default, prepends a timestamp to the message; set second argument to 0 or False to disable
def message(strMessage, stamp = True):
    global gp, logFile
    if stamp == True:
        strMessage = time.asctime() + " - " + strMessage
    #print strMessage
    gp.AddMessage(strMessage)
    if logFile:
        logFile.write(strMessage + "\n")
        logFile.flush()

def warning(strMessage, stamp = True):
    global gp, logFile
    if stamp == True:
        strMessage = time.asctime() + " - " + strMessage
    #print strMessage
    gp.AddWarning(strMessage)
    if logFile:
        logFile.write(strMessage + "\n")
        logFile.flush()

def error(strMessage, stamp = True):
    global gp, logFile
    if stamp == True:
        strMessage = time.asctime() + " - " + strMessage
    #print strMessage
    gp.AddError(strMessage)
    if logFile:
        logFile.write(strMessage + "\n")
        logFile.flush()

Re: Dumb question - can I write standalone python script to run without arcgis?

DanPatterson_Retired — Wed, 03 Nov 2010 20:31:23 GMT

Logan
good suggestion...and you need not even comment out the print statement, in fact you could get ready for python 3.0 by adding these blocks
    try
       print strMessage     #pre 3.0
    except
       print (strMessage)   #3.0 +
    gp.AddMessage(strMessage)
the print statement will simply become heat energy if gp is being used and vica versa.

Re: Dumb question - can I write standalone python script to run without arcgis?

FrankPerks — Sat, 11 Dec 2021 15:09:05 GMT

Frank...unfortunately it doesn't print to other IDE's output...don't use console...too dark and gloomy and reminds me of the old DOS days

Pycharm / Komodo python IDE's are fine with the message printing(I assume wingide is too) :cool: IDLE/pywin32 is not an IDE, they are mistakes.

If you really want a decent Python IDE i honestly suggest looking into PyCharm (try it for 30 days, its also 50% off right now). If you don't want to spend money then i suggest NetBeans, or PyScripter. (I refuse to acknowledge pydev since its based off the horror that is known as eclipse).

It's for that reason that I wrote my own message(), warning() and error() methods. In addition to logging to a text file, it's exactly 3 places that I need to change if I need print statements or not, not dozens of lines littered throughout the script.

Most of the time I don't need print messages, but if I'm debugging in PyScripter or PythonWin (but not winpdb which runs the script in a separate console window from the GUI), I'll uncomment my print statement in each of the 3 methods.
# Helper methods for writing messages, warnings and errors to the geoprocessor as well as a logfile
# By default, prepends a timestamp to the message; set second argument to 0 or False to disable
def message(strMessage, stamp = True):
    global gp, logFile
    if stamp == True:
        strMessage = time.asctime() + " - " + strMessage
    #print strMessage
    gp.AddMessage(strMessage)
    if logFile:
        logFile.write(strMessage + "\n")
        logFile.flush()

def warning(strMessage, stamp = True):
    global gp, logFile
    if stamp == True:
        strMessage = time.asctime() + " - " + strMessage
    #print strMessage
    gp.AddWarning(strMessage)
    if logFile:
        logFile.write(strMessage + "\n")
        logFile.flush()

def error(strMessage, stamp = True):
    global gp, logFile
    if stamp == True:
        strMessage = time.asctime() + " - " + strMessage
    #print strMessage
    gp.AddError(strMessage)
    if logFile:
        logFile.write(strMessage + "\n")
        logFile.flush()

You should really look into the python logging, its wonderful: http://docs.python.org/library/logging.html

However you need to create a gp friendly logger... heres an example:

import logging
import sys


_GP_MESSAGE_DEFS = {
        logging.CRITICAL : "AddError",
        logging.ERROR : "AddError",
        logging.WARNING : "AddWarning",
        logging.INFO : "AddMessage",
        logging.DEBUG : "AddMessage",
    }

class GPHandler(logging.Handler):
    """
        Geoprocessor friendly logging module
    """
    def __init__(self, level=logging.NOTSET, gp=None):
        self.gp = gp
        logging.Handler.__init__(self, level)

    def emit(self, record):
        """
            Woop.
        """
        message = self.format(record)
        if self.gp:
            source = gp
        else:
            source = __import__("arcpy")

        # retrive the functor and call it with the message
        getattr(source, _GP_MESSAGE_DEFS[record.levelno])(message)

_logger = logging.getLogger("test")
_logger.setLevel(logging.DEBUG)

# sadily i have no idea where this object type is located
if type(sys.stdout) != "<type 'geoprocessing sys.stdout object'>":
    handler = logging.StreamHandler()
else:
    # change for arc9.3
    handler = GPHandler()

handler.setFormatter(logging.Formatter("%(asctime)10s | %(name)s | %(message)s",
                                       "%Y%m%d %H:%M:%S"))
_logger.addHandler(handler)

_logger.debug("Message")
_logger.info("Info message")
_logger.warning("Warning")
_logger.error("error")
_logger.critical("error")

This gives an output of:

20101103 21:36:45 | test | Message
20101103 21:36:52 | test | Info message
WARNING: 20101103 21:36:52 | test | Warning
ERROR: 20101103 21:36:52 | test | error
ERROR: 20101103 21:36:52 | test | error

If you run it from not within arcmap it goes to normal console streams. If you run it via arcgis it goes to the gp addmessage/etc.

Re: Dumb question - can I write standalone python script to run without arcgis?

JasonScheirer — Thu, 04 Nov 2010 00:42:49 GMT

print x is a syntax error in Python 3.0, so you're not future-proofing your code nearly as well as you think.

Starting from 2.6, you can import print as a function from the future with from __future__ import print_function directive and use print as a 3.x style function across the board in your script.

Re: Dumb question - can I write standalone python script to run without arcgis?

FrankPerks — Thu, 04 Nov 2010 01:16:38 GMT

print x is a syntax error in Python 3.0, so you're not future-proofing your code nearly as well as you think.

Starting from 2.6, you can import print as a function from the future with from __future__ import print_function directive and use print as a 3.x style function across the board in your script.

Also by doing the from __future__ import print_function, you add some amazing functionality in the form of completely breaking any chance of the 9.3 or less crowd from using your script (which is a big reality considering how many people probably still use < 10.0)

If you reallllyyyyyy want to futureproof print (because esri is bound to go to python 3.0 any day now :o). Don't use it. Use logging. Or use sys.stdout.write(). Or even just use ESRI's AddMessage.

Print is evil.