topic Re: addlayer error!! in Python Questions

addlayer error!!

LefterisKoumis — Wed, 06 Aug 2014 20:58:59 GMT

I am new in python but this script should be easy to process. Instead I get:

arcpy.mapping.AddLayer(myDF,addlayer) NameError: name 'addlayer' is not defined

Here is the script:

import arcpy

thisMap = arcpy.mapping.MapDocument("CURRENT")

myDF = arcpy.mapping.ListDataFrames(thisMap)[0]

myLayers = arcpy.mapping.ListLayers(myDF)

for lyr in myLayers:

if lyr.name == "CNNDB":

addlayer = arcpy.mapping.Layer(lyr)

print "got it"

arcpy.mapping.AddLayer(myDF,addlayer,"AUTO ARRANGE")

arcpy.CreateFolder_management(r"D:\GIS_data", "test")

arcpy.mapping.ExportToPDF(thisMap, r"D:\GIS_data\test\Project.pdf",300,"BEST",layers_attributes="LAYERS_AND_ATTRIBUTES")

#Do you see any errors? Thank you.

Re: addlayer error!!

XanderBakker — Wed, 06 Aug 2014 21:33:40 GMT

Not sure what you are trying to do with this code. You loop through the layers in an MXD and check if the name equals "CNNDB". If that's the case you try to set a variable "addlayer". I don't think you should try to create a layer from a layer object.

Next you try to add the layer to the dataframe (where the layer already exists), although the code does not run that far. And you intent to export the map to PDF. Is the loop through your layer really useful?

Kind regards, Xander

Re: addlayer error!!

LefterisKoumis — Wed, 06 Aug 2014 21:41:45 GMT

Ok, I modified my code....but I still getting an error.

What I am trying to do is to loop through the layers of the current map and if a specific layer is found, then it will be copied onto a new map and then print the pdf of the new map.

Does it make sense?

import arcpy

thisMap = arcpy.mapping.MapDocument("CURRENT")

myDF = arcpy.mapping.ListDataFrames(thisMap)[0]

arcpy.CreateFolder_management(r"D:\GIS_data", "test")

newmap = arcpy.mapping.MapDocument(r"D:\GIS_data\test\new.mxd")

newdf = arcpy.mapping.ListDataFrames(newmap)[0]

myLayers = arcpy.mapping.ListLayers(myDF)

for lyr in myLayers:

if lyr.name == "CNNDB":

addlayer = arcpy.mapping.Layer(lyr)

arcpy.mapping.AddLayer(newdf,addlayer,"AUTO ARRANGE")

arcpy.RefreshTOC

arcpy.RefreshActiveView

arcpy.mapping.ExportToPDF(newmap, r"D:\GIS_data\test\Project.pdf",300,"BEST",layers_attributes="LAYERS_AND_ATTRIBUTES")

Re: addlayer error!!

XanderBakker — Wed, 06 Aug 2014 21:48:47 GMT

I see you are trying to create a new MXD through python by just accessing a non existing mxd file in a just created folder. That will not work. See the blog post below with an example of using ArcObjects inside Python for that purpose.

Create a new MXD through Python.‌

This is rather complex. You might want to consider creating an empty mxd file and copy that file for creating a new MXD.

Kind regards, Xander

Re: addlayer error!!

9628807811 — Wed, 06 Aug 2014 22:10:15 GMT

The addlayer variable is defined inside the for loop scope so it's not seen outside the loop, try to declare it before your loop then assign your matched layer to it.

Re: addlayer error!!

LefterisKoumis — Wed, 06 Aug 2014 22:30:36 GMT

Sorry I am novice in Python. How do you declare a variable that if no layers are defined yet? Can I a declare without point at a layer?

Re: addlayer error!!

Luke_Pinner — Sun, 12 Dec 2021 08:24:20 GMT

@Ahmed that is not correct. For loops do not have their own namespace, so the variable is in the local scope. Consider this:

for i in range(2):
    loopvar = i * 2

print 'loopvar was defined in the loop and its value is {0}'.format(loopvar)

The above code snippet works fine and prints:

loopvar was defined in the loop and its value is 2

Re: addlayer error!!

LefterisKoumis — Fri, 08 Aug 2014 01:04:22 GMT

So, Luke, in my case why the addlayer is undefined?

Re: addlayer error!!

Luke_Pinner — Sun, 12 Dec 2021 08:24:23 GMT

Is this your full code? Do you have any try/except clauses in there that might be hiding earlier exceptions?

I can't see how you would even get to `arcpy.mapping.AddLayer(newdf,addlayer,"AUTO ARRANGE")` as the `addlayer = arcpy.mapping.Layer(lyr)` would raise an exception anyway as `lyr` is a layer object, not a string.

Also, the AddLayer method will raise an exception as "AUTO ARRANGE" is an invalid value, it must be one of ['TOP', 'AUTO_ARRANGE', 'BOTTOM'] Note the "_" underscore in "AUTO_ARRANGE".

Here is some code to get you started:

import arcpy

thisMap = arcpy.mapping.MapDocument("CURRENT")
myDF = arcpy.mapping.ListDataFrames(thisMap)[0]
if not arcpy.Exists(r"D:\GIS_data\test"):
    arcpy.CreateFolder_management(r"D:\GIS_data", "test")
templatemap = arcpy.mapping.MapDocument(r"D:\GIS_data\template.mxd") #an existing empty mxd
templatedf = arcpy.mapping.ListDataFrames(templatemap)[0]

myLayers = arcpy.mapping.ListLayers(myDF,"CNNDB")
if myLayers:
    arcpy.mapping.AddLayer(templatedf,myLayers[0],"AUTO_ARRANGE")
    templatemap.saveACopy(r"D:\GIS_data\test\new.mxd")
    newmap=arcpy.mapping.MapDocument(r"D:\GIS_data\test\new.mxd")

Notes:

arcpy.mapping.MapDocument requires an existing MXD, it can not create a new one. Use an empty mxd as a template.
You can pass a layer name (or partial name + wildcard *) to the arcpy.mapping.ListLayers method.

Re: addlayer error!!

XanderBakker — Fri, 08 Aug 2014 02:48:46 GMT

Thanx Luke, for adding an example and the good explanation. This saves me some time

Re: addlayer error!!

XanderBakker — Fri, 08 Aug 2014 02:50:41 GMT

That was explained by Luke earlier. In case it finds the layer with the name you specify you try to pass a layer object to the arcpy.mapping.Layer() that expects a string...

Re: addlayer error!!

DanPatterson_Retired — Fri, 08 Aug 2014 13:29:02 GMT

Is it possible that making a conventional toolbox (*.tbx) would have been a simpler approach? I am just wondering why you have opted for this level of complexity when the tasks to perform seem relatively simple? I am a curious as to what routes people take (ie ArcObjects, versus Addins vs tbx's versus standalone applications)

Re: addlayer error!!

CARMETSandrine — Fri, 08 Aug 2014 13:44:53 GMT

I understand your point, but I have more than 500 shapefiles with their labels (contour field) to create and then export all of them to CAD. Even if I create a toolbox, it takes to much time to do:

- Clip Raster

- Create Contour

- Convert Labels to Annotations

- Export to CAD

So I thought by creating a tool that compile all this functions will saved me time and then share it to my colleagues.

And it was a good opportunity to see how python works for future tasks.

Re: addlayer error!!

XanderBakker — Fri, 08 Aug 2014 13:46:49 GMT

I agree with Dan, what you describe can be done with a conventional toolbox that holds a simple python script to perform the analysis.

Re: addlayer error!!

XanderBakker — Fri, 08 Aug 2014 14:10:05 GMT

It seems this is also suggested to you at your thread: How to use defined parameters in a tool ?‌

I think it's better to continue this discussion at your own thread

Re: addlayer error!!

CARMETSandrine — Fri, 08 Aug 2014 14:12:10 GMT

OK ,

but for the"convert labels to annotation", is there a simple way to ingrate it into a python script ? (because that's what makes me lose time, imagine I have more than 500 shapefiles to create and then convert all the labels to annotation to export all of them to CAD).

That's why I was asking you to understand the "add layer" , to after activate the labels and then convert into annotation, all of this in the same python script.

(Sorry if my english is not good, I'm french)

Thanks.

Re: addlayer error!!

CARMETSandrine — Fri, 08 Aug 2014 14:14:59 GMT

OK I think I just can not fully explain myself.

I will just continue to do it manually.

Thanks for every thing.

Re: addlayer error!!

XanderBakker — Fri, 08 Aug 2014 16:03:12 GMT

Don't worry about your English, it's fine.

The help page with examples for the tool you need can be found here:

Tiled Labels To Annotation (Cartography)

Kind regards, Xander

Re: addlayer error!!

JamesCrandall — Fri, 08 Aug 2014 18:34:15 GMT

This is untested and I have not fully vetted this, but I think you can try to reference the path name instead of trying to add the layer from another .mxd. You can use arcpy.Describe to get the fully qualified path of the layer:

import arcpy
thisMap = arcpy.mapping.MapDocument("CURRENT")
myDF = arcpy.mapping.ListDataFrames(thisMap)[0]
arcpy.CreateFolder_management(r"D:\GIS_data", "test")
newmap = arcpy.mapping.MapDocument(r"D:\GIS_data\test\new.mxd")
newdf = arcpy.mapping.ListDataFrames(newmap)[0]
myLayers = arcpy.mapping.ListLayers(myDF)
for lyr in myLayers:
    if lyr.name == "CNNDB":
      #set the path of the layer
      desc = arcpy.Describe(lyr)
      if hasattr(desc, "catalogPath"):
          addlayer = desc.catalogPath

#make a feaure layer to add to the new map
arcpy.MakeFeatureLayer_management(addlayer, "layernametocallit")
arcpy.mapping.AddLayer(newdf,"layernametocallit","AUTO ARRANGE")
arcpy.RefreshTOC
arcpy.RefreshActiveView

Re: addlayer error!!

JamesCrandall — Sun, 12 Dec 2021 08:24:26 GMT

I just whipped this together, and it doesn't fully meet your requirments but it does the first half of your task. You will need to get the rest implemented (from converting to anno onwards). Also, I ran into little problems that mostly got solved by NOT using .shp files and just setup File Geodatabases --- which is not a bad plan anyway. Especially dealing with rasters for some reason, processing them outside of .gdb's is kwirky.


ras = r'H:\Documents\inputraster.tif'
ras_ws = r'H:\Documents\rasters\clippedrasters.gdb'
ras_countours = r'H:\Documents\rasters\contours.gdb'
shp_ws = r'H:\Documents\shps'
arcpy.env.workspace = shp_ws
rascount = 1
for fc in arcpy.ListFeatureClasses():
    print fc
    #create the clip rasters
    arcpy.Clip_management(ras,"#", ras_ws + "\\ras" + str(rascount),fc, "0", "ClippingGeometry")
    rascount = rascount + 1


#create the contours from the clipped rasters
### see if spatial analyst extension is available for use
availability = arcpy.CheckExtension("Spatial")
if availability == "Available":
     arcpy.CheckOutExtension("Spatial")
     arcpy.AddMessage("SA Ext checked out")
else:
     arcpy.AddError("%s extension is not available (%s)"%("Spatial Analyst Extension",availability))
     arcpy.AddError("Please ask someone who has it checked out but not using to turn off the extension")
     


arcpy.env.workspace = ras_ws
contourcount = 1
for ras in arcpy.ListRasters():
    outname = ras_countours + "\\contour" + str(contourcount)
    print "ountname: " + outname
    arcpy.sa.Contour(ras, outname, 200, 0)
    contourcount = contourcount + 1


#check the extension back in
arcpy.CheckInExtension("Spatial")