topic Re: Error When Running Calculate Value in ModelBuilder Questions

Error When Running Calculate Value

ChrisHolmes — Wed, 31 Aug 2016 22:21:45 GMT

Hello Everyone,

I have a model which runs the calculate value tool:

The code in the tool is:

When the model runs the following errors are displayed:

I'm not sure what the errors are related to. What's strange is that the code does seem to execute: it displays the extent of the site_polygon layer, sets the scale to 1:4000, then creates the JPG file.

Any insights appreciated. Thanks!

Re: Error When Running Calculate Value

DanPatterson_Retired — Thu, 01 Sep 2016 01:20:15 GMT

return 'true' perhaps return True

boolean is not a string

Re: Error When Running Calculate Value

XanderBakker — Thu, 01 Sep 2016 03:50:59 GMT

Just wondering why you would want to use the ModelBuilder for this. It would be a lot more stable if you would create a script (and if necessary a tool from the script) to do this.

Re: Error When Running Calculate Value

ChrisHolmes — Thu, 01 Sep 2016 13:47:46 GMT

Thanks Dan. Funny how it's easy to miss the tiny things. It didn't fix the errors though. I did find though that by commenting out mxd.save() it executes correctly. Not sure why it doesn't want to save to that location.

Re: Error When Running Calculate Value

ChrisHolmes — Thu, 01 Sep 2016 13:50:59 GMT

Actually, that would be my preference. I just haven't figured out yet how to pass a parameter from a model to a script. As you see I need to pass in a parameter LocNo.

Can you point me to an example that would help me figure out how to do that? I would still need to make it part of a script tool as this is part of a larger model.

Thanks Xander!

Re: Error When Running Calculate Value

XanderBakker — Thu, 01 Sep 2016 13:55:31 GMT

I think that if you can create this variable in your model, you will also be able to create it within a script. I wouldn't include ModelBuilder at all, but I'm note sure what the content of LocNo is and what it is based on.

Re: Error When Running Calculate Value

ChrisHolmes — Thu, 01 Sep 2016 14:14:05 GMT

LocNo is just a string value that would be provided by the end user.

Thanks

Re: Error When Running Calculate Value

XanderBakker — Thu, 01 Sep 2016 14:17:05 GMT

Then there would be no problem to use a script instead of a a model. The script should also check for existence of the MXD file before you try to open it (especially if it is a string provided by a user).

Re: Error When Running Calculate Value

ChrisHolmes — Thu, 01 Sep 2016 14:22:29 GMT

So would the code in the script be the same as what I put in the Calculate Value tool and does the passing the parameter part get handled in properties > parameters when I create the script tool?

Re: Error When Running Calculate Value

XanderBakker — Thu, 01 Sep 2016 15:18:05 GMT

I have attached a sample toolbox. In the configuration of the script tool, you define a parameter. I called it "Loc No" and it is of type String. This value can be read from the script using arcpy.GetParameterAsText(0). The code in the python script is pretty much the same as you have.

Re: Error When Running Calculate Value

ChrisHolmes — Thu, 01 Sep 2016 15:28:29 GMT

Great, thanks very much Xander.

Re: Error When Running Calculate Value

ChrisHolmes — Thu, 01 Sep 2016 17:23:53 GMT

Hi Xander,

I'm going to attach a file with a table showing on the left the code in the Calculate Value tool and on the right the code in the python script you sent me (thanks again!). The row below the row with the code shows the jpg file created using both methods. The one for the Calculate Value tool shows the correct image, the one for the python script shows the mxd as it appears when it's opened up (so it doesn't seem to do what's in the code). To me the code in both methods looks the same so I don't know why the code in the python script doesn't seem to run?

Re: Error When Running Calculate Value

XanderBakker — Sun, 12 Dec 2021 08:47:34 GMT

Strange, supposedly arcpy will refresh the active view when something is changed. I would have to set up a similar situation te be able to track the issue, but I don't have time for that. Could you change the code to this (some additional messages):

def main():
    import arcpy
    # will overwrite existing jpg
    arcpy.env.overwriteOutput = True

    # read the parameter from the tool
    loc_no = arcpy.GetParameterAsText(0)

    # define the path of the mxd
    mxd_file = r'H:\chris\{0}\{0} - actual_use.mxd'.format(loc_no)
    jpg_file = r'H:\chris\{0}\{0} - actual_use.jpg'.format(loc_no)
    if arcpy.Exists(mxd_file):
        arcpy.AddMessage("Using MXD {0}".format(mxd_file))
        try:
            mxd = arcpy.mapping.MapDocument(mxd_file)
            df = arcpy.mapping.ListDataFrames(mxd)[0]
            arcpy.AddMessage("DF extent on startup is: {0}".format(df.extent))
            arcpy.AddMessage("DF scale on startup is: {0}".format(df.scale))
            lyr = arcpy.mapping.ListLayers(mxd, 'site_polygon', df)[0]
            ext = lyr.getExtent()
            arcpy.AddMessage("extent of lyr: {0}".format(ext))
            df.ext = ext
            df.scale = 4000
            arcpy.AddMessage("DF extent after assignment is: {0}".format(df.extent))
            arcpy.AddMessage("DF scale after assignment is: {0}".format(df.scale))
            arcpy.AddMessage("Exporting to JPEG: {0}".format(jpg_file))
            arcpy.mapping.ExportToJPEG(mxd, jpg_file)
            mxd.save()
            del mxd
        except Exception as e:
            arcpy.AddError("Error: {0}".format(e))
    else:
        arcpy.AddWarning("MXD {0} not found!".format(mxd_file))

if __name__ == '__main__':
    main()‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

... just to see what is going on?

Re: Error When Running Calculate Value

ChrisHolmes — Thu, 01 Sep 2016 19:24:54 GMT

Thanks Xander. Here are the results:

Executing: ExportMXD2JPG2 LOC2016-003

Start Time: Thu Sep 01 13:22:29 2016

Running script ExportMXD2JPG2...

Using MXD H:\chris\LOC2016-003\LOC2016-003 - actual_use.mxd

DF extent on startup is: -9047.84819850156 5650698.4605047 -8349.34680149874 5651193.7614953 NaN NaN NaN NaN

DF scale on startup is: 4000.0

extent of lyr: -10106.7650000002 5656720.382 -10069.7270000003 5656763.791 NaN NaN NaN NaN

DF extent after assignment is: -9047.84819850156 5650698.4605047 -8349.34680149874 5651193.7614953 NaN NaN NaN NaN

DF scale after assignment is: 4000.0

Exporting to JPEG: H:\chris\LOC2016-003\LOC2016-003 - actual_use.jpg

Completed script ExportMXD2JPG2...

Succeeded at Thu Sep 01 13:22:59 2016 (Elapsed Time: 29.68 seconds)

Re: Error When Running Calculate Value

XanderBakker — Sun, 12 Dec 2021 08:47:36 GMT

OK, so the dataframe extent is not being changed when the layer extent is assigned. Could you try this code?

def main():
    import arcpy
    # will overwrite existing jpg
    arcpy.env.overwriteOutput = True

    # read the parameter from the tool
    loc_no = arcpy.GetParameterAsText(0)

    # define the path of the mxd
    mxd_file = r'H:\chris\{0}\{0} - actual_use.mxd'.format(loc_no)
    jpg_file = r'H:\chris\{0}\{0} - actual_use.jpg'.format(loc_no)
    if arcpy.Exists(mxd_file):
        arcpy.AddMessage("Using MXD {0}".format(mxd_file))
        try:
            mxd = arcpy.mapping.MapDocument(mxd_file)
            df = arcpy.mapping.ListDataFrames(mxd)[0]
            arcpy.AddMessage("DF extent on startup is: {0}".format(df.extent))
            arcpy.AddMessage("DF scale on startup is: {0}".format(df.scale))
            lyr = arcpy.mapping.ListLayers(mxd, 'site_polygon', df)[0]
            ext = lyr.getExtent()
            arcpy.AddMessage("extent of lyr: {0}".format(ext))
            new_extent = df.ext
            new_extent.XMin, new_extent.YMin = ext.XMin, ext.YMin
            new_extent.XMax, new_extent.YMax = ext.XMax, ext.YMax
            arcpy.AddMessage("extent of new_extent: {0}".format(new_extent))
            df.ext = new_extent
            df.scale = 4000
            arcpy.AddMessage("DF extent after assignment is: {0}".format(df.extent))
            arcpy.AddMessage("DF scale after assignment is: {0}".format(df.scale))
            arcpy.AddMessage("Exporting to JPEG: {0}".format(jpg_file))
            arcpy.mapping.ExportToJPEG(mxd, jpg_file)
            mxd.save()
            del mxd
        except Exception as e:
            arcpy.AddError("Error: {0}".format(e))
    else:
        arcpy.AddWarning("MXD {0} not found!".format(mxd_file))

if __name__ == '__main__':
    main()‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Re: Error When Running Calculate Value

ChrisHolmes — Thu, 01 Sep 2016 20:23:42 GMT

Thanks Xander. When I run that code, I get the following error message:

Executing: ExportMXD2JPG3 LOC2016-003

Start Time: Thu Sep 01 14:21:14 2016

Running script ExportMXD2JPG3...

Using MXD H:\chris\LOC2016-003\LOC2016-003 - actual_use.mxd

DF extent on startup is: -9047.84819850156 5650698.4605047 -8349.34680149874 5651193.7614953 NaN NaN NaN NaN

DF scale on startup is: 4000.0

extent of lyr: -10106.7650000002 5656720.382 -10069.7270000003 5656763.791 NaN NaN NaN NaN

Error: 'DataFrame' object has no attribute 'ext'

Completed script ExportMXD2JPG3...

Failed to execute (ExportMXD2JPG3).

Failed at Thu Sep 01 14:21:32 2016 (Elapsed Time: 17.89 seconds)

Thanks for your help, very much appreciated!

Re: Error When Running Calculate Value

DanPatterson_Retired — Thu, 01 Sep 2016 20:28:22 GMT

the df extent has to be set to the extent right now it isn't being assigned properly as it is further on... (I think... Xander you will have to check

Re: Error When Running Calculate Value

ChrisHolmes — Thu, 01 Sep 2016 20:41:42 GMT

Thanks Dan. That seems to have fixed the error. The results now display as:

Executing: ExportMXD2JPG3 LOC2016-003

Start Time: Thu Sep 01 14:35:03 2016

Running script ExportMXD2JPG3...

Using MXD H:\chris\LOC2016-003\LOC2016-003 - actual_use.mxd

DF extent on startup is: -9047.84819850156 5650698.4605047 -8349.34680149874 5651193.7614953 NaN NaN NaN NaN

DF scale on startup is: 4000.0

extent of lyr: -10106.7650000002 5656720.382 -10069.7270000003 5656763.791 NaN NaN NaN NaN

extent of new_extent: -10106.7650000002 5656720.382 -10069.7270000003 5656763.791 NaN NaN NaN NaN

DF extent after assignment is: -9047.84819850156 5650698.4605047 -8349.34680149874 5651193.7614953 NaN NaN NaN NaN

DF scale after assignment is: 4000.0

Exporting to JPEG: H:\chris\LOC2016-003\LOC2016-003 - actual_use.jpg

Completed script ExportMXD2JPG3...

Succeeded at Thu Sep 01 14:35:40 2016 (Elapsed Time: 36.85 seconds)

Still seems though that the extents are not changing.

Re: Error When Running Calculate Value

DanPatterson_Retired — Thu, 01 Sep 2016 20:54:17 GMT

ahhhh/! new_extent = df.extent or you will have to wait for Xander

Re: Error When Running Calculate Value

ChrisHolmes — Thu, 01 Sep 2016 21:40:31 GMT

It seems to have dealt with the error. But the data frame extents still do not seem to take the value of new_extent.

Thank you Dan