Hey everybody, I am creating python toolbox and one of the tools adds a bunch of fields to a feature class that the user chooses and after wards calculates those fields with values from the original feature class. I run into the issue that the field calculations can't run because the fields haven't been added yet. This is the code I use: import arcpy class Toolbox ( object ) : def __init__ ( self ) : """Define the toolbox (the name of the toolbox is the name of the .pyt file).""" self . label = "My first python toolbox" self . alias = "Examples" # List of tool classes associated with this toolbox self . tools = [ Tool1 ] class Tool1 ( object ) : def __init__ ( self ) : """Define the tool (tool name is the name of the class).""" self . label = "Nena Street Tool" self . description = "Example showing how to create a value table tool with drop downs" self . canRunInBackground = False def getParameterInfo ( self ) : """Define parameter definitions""" # # Define Parameter 0 # # Param0 will be a FeatureLayer param0 = arcpy . Parameter ( displayName = "Your Street Layer" , name = "Site_layer" , datatype = "GPFeatureLayer" , parameterType = "Required" , direction = "Input" ) # # Define Parameter 1 # param1 = arcpy . Parameter ( displayName = "" , name = "Activity_layers" , datatype = "GPValueTable" , parameterType = "Optional" , direction = "Input" ) param1 . columns = [ [ "String" , "NENA Field" ] , [ "String" , "Your Field" ] ] # This says the filter on the second column will be a value List param1 . filters [ 1 ] . type = "ValueList" param1 . value = "Source; Updatedate; Effective; Expire; RCL_NGUID; AdNumPre_L; AdNumPre_R; FromAddr_L; ToAddr_L; FromAddr_R; ToAddr_R; Parity_L; Parity_R" # This adds a dummy value to the list, this will get overwritten by the updateParameters function param1 . filters [ 1 ] . list = [ "Please Select a street layer" ] # Create a list of parameters and return params = [ param0 , param1 ] return params def isLicensed ( self ) : """Set whether tool is licensed to execute.""" return True def updateParameters ( self , parameters ) : if parameters [ 0 ] . altered : fields = arcpy . ListFields ( parameters [ 0 ] . value ) mylist = [ ] for field in fields : mylist . append ( field . name ) parameters [ 1 ] . filters [ 1 ] . list = mylist return def updateMessages ( self , parameters ) : """Modify the messages created by internal validation for each tool parameter. This method is called after internal validation.""" return def execute ( self , parameters , messages ) : """The source code of the tool.""" try : # Some code to show that I had managed to get what I wanted intot the ValueTable data = parameters [ 1 ] . values arcpy . AddField_management ( parameters [ 0 ] . value , "Source" , "TEXT" , "" , "" , "75" , "" , "NULLABLE" , "NON_REQUIRED" , "" ) arcpy . AddField_management ( parameters [ 0 ] . value , "DateUpdate" , "DATE" , "" , "" , "" , "" , "NULLABLE" , "NON_REQUIRED" , "" ) arcpy . AddField_management ( parameters [ 0 ] . value , "Effective" , "DATE" , "" , "" , "" , "" , "NULLABLE" , "NON_REQUIRED" , "" ) search = 'Source' for sublist in data : if sublist [ 0 ] == search : final = sublist mysource = final [ 1 ] sourceData = "[" + mysource + "]" arcpy . CalculateField_management ( parameters [ 0 ] . value , "Source" , sourceData , "VB" , "" ) break except arcpy . ExecuteError : messages . addErrorMessage ( arcpy . GetMessages ( ) ) In line 75 I add the "Source" field and in line 84 I try to calculate it, but I get the error that the "Source" field does not exist. Any help would be appreciated. Tim

nav[aria-label="Primary Navigation"] { padding: 0; & ul { list-style: none; width: 100%; display: flex; flex-direction: row; justify-content: start; align-items: start; gap: 30px; padding: 0; & li { margin: 0; } & ul li { list-style: none; } } }

Wait for AddField to finish until running CalculatField

TimWitt2

Hey everybody,

I am creating python toolbox and one of the tools adds a bunch of fields to a feature class that the user chooses and after wards calculates those fields with values from the original feature class. I run into the issue that the field calculations can't run because the fields haven't been added yet.

This is the code I use:

<SPAN class="keyword token">import</SPAN> arcpy&nbsp; 
&nbsp; 
<SPAN class="keyword token">class</SPAN> <SPAN class="token class-name">Toolbox</SPAN><SPAN class="punctuation token">(</SPAN>object<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">def</SPAN> <SPAN class="token function">__init__</SPAN><SPAN class="punctuation token">(</SPAN>self<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="string token">"""Define the toolbox (the name of the toolbox is the name of the .pyt file)."""</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; self<SPAN class="punctuation token">.</SPAN>label <SPAN class="operator token">=</SPAN> <SPAN class="string token">"My first python toolbox"</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; self<SPAN class="punctuation token">.</SPAN>alias <SPAN class="operator token">=</SPAN> <SPAN class="string token">"Examples"</SPAN>&nbsp; 
&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token"># List of tool classes associated with this toolbox&nbsp; </SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; self<SPAN class="punctuation token">.</SPAN>tools <SPAN class="operator token">=</SPAN> <SPAN class="punctuation token">[</SPAN>Tool1<SPAN class="punctuation token">]</SPAN>&nbsp; 
&nbsp; 
<SPAN class="keyword token">class</SPAN> <SPAN class="token class-name">Tool1</SPAN><SPAN class="punctuation token">(</SPAN>object<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">def</SPAN> <SPAN class="token function">__init__</SPAN><SPAN class="punctuation token">(</SPAN>self<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="string token">"""Define the tool (tool name is the name of the class)."""</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; self<SPAN class="punctuation token">.</SPAN>label <SPAN class="operator token">=</SPAN> <SPAN class="string token">"Nena Street Tool"</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; self<SPAN class="punctuation token">.</SPAN>description <SPAN class="operator token">=</SPAN> <SPAN class="string token">"Example showing how to create a value table tool with drop downs"</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; self<SPAN class="punctuation token">.</SPAN>canRunInBackground <SPAN class="operator token">=</SPAN> <SPAN class="token boolean">False</SPAN>&nbsp; 
&nbsp; 
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">def</SPAN> <SPAN class="token function">getParameterInfo</SPAN><SPAN class="punctuation token">(</SPAN>self<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="string token">"""Define parameter definitions"""</SPAN>&nbsp; 
&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token">#&nbsp; </SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token"># Define Parameter 0&nbsp; </SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token">#&nbsp; </SPAN>
&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token"># Param0 will be a FeatureLayer </SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; param0 <SPAN class="operator token">=</SPAN> arcpy<SPAN class="punctuation token">.</SPAN>Parameter<SPAN class="punctuation token">(</SPAN>displayName <SPAN class="operator token">=</SPAN> <SPAN class="string token">"Your Street Layer"</SPAN><SPAN class="punctuation token">,</SPAN>name<SPAN class="operator token">=</SPAN><SPAN class="string token">"Site_layer"</SPAN><SPAN class="punctuation token">,</SPAN>datatype<SPAN class="operator token">=</SPAN><SPAN class="string token">"GPFeatureLayer"</SPAN><SPAN class="punctuation token">,</SPAN>parameterType<SPAN class="operator token">=</SPAN><SPAN class="string token">"Required"</SPAN><SPAN class="punctuation token">,</SPAN>direction<SPAN class="operator token">=</SPAN><SPAN class="string token">"Input"</SPAN><SPAN class="punctuation token">)</SPAN>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token">#&nbsp; </SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token"># Define Parameter 1&nbsp; </SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token">#&nbsp; </SPAN>
&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; param1 <SPAN class="operator token">=</SPAN> arcpy<SPAN class="punctuation token">.</SPAN>Parameter<SPAN class="punctuation token">(</SPAN>displayName <SPAN class="operator token">=</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">,</SPAN>name<SPAN class="operator token">=</SPAN><SPAN class="string token">"Activity_layers"</SPAN><SPAN class="punctuation token">,</SPAN>datatype<SPAN class="operator token">=</SPAN><SPAN class="string token">"GPValueTable"</SPAN><SPAN class="punctuation token">,</SPAN>parameterType<SPAN class="operator token">=</SPAN><SPAN class="string token">"Optional"</SPAN><SPAN class="punctuation token">,</SPAN> direction<SPAN class="operator token">=</SPAN><SPAN class="string token">"Input"</SPAN><SPAN class="punctuation token">)</SPAN>&nbsp; 
&nbsp; 
 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; param1<SPAN class="punctuation token">.</SPAN>columns<SPAN class="operator token">=</SPAN><SPAN class="punctuation token">[</SPAN><SPAN class="punctuation token">[</SPAN><SPAN class="string token">"String"</SPAN><SPAN class="punctuation token">,</SPAN><SPAN class="string token">"NENA Field"</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">,</SPAN><SPAN class="punctuation token">[</SPAN><SPAN class="string token">"String"</SPAN><SPAN class="punctuation token">,</SPAN><SPAN class="string token">"Your Field"</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">]</SPAN>&nbsp; 
&nbsp; 
&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token"># This says the filter on the second column will be a value List&nbsp; </SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; param1<SPAN class="punctuation token">.</SPAN>filters<SPAN class="punctuation token">[</SPAN><SPAN class="number token">1</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>type<SPAN class="operator token">=</SPAN><SPAN class="string token">"ValueList"</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; param1<SPAN class="punctuation token">.</SPAN>value <SPAN class="operator token">=</SPAN> <SPAN class="string token">"Source; Updatedate; Effective; Expire; RCL_NGUID; AdNumPre_L; AdNumPre_R; FromAddr_L; ToAddr_L; FromAddr_R; ToAddr_R; Parity_L; Parity_R"</SPAN>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token"># This adds a dummy value to the list, this will get overwritten by the updateParameters function&nbsp; </SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; param1<SPAN class="punctuation token">.</SPAN>filters<SPAN class="punctuation token">[</SPAN><SPAN class="number token">1</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>list<SPAN class="operator token">=</SPAN><SPAN class="punctuation token">[</SPAN><SPAN class="string token">"Please Select a street layer"</SPAN><SPAN class="punctuation token">]</SPAN>&nbsp; 
&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token"># Create a list of parameters and return&nbsp; </SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; params <SPAN class="operator token">=</SPAN> <SPAN class="punctuation token">[</SPAN>param0<SPAN class="punctuation token">,</SPAN>param1<SPAN class="punctuation token">]</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">return</SPAN> params&nbsp; 
&nbsp; 
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">def</SPAN> <SPAN class="token function">isLicensed</SPAN><SPAN class="punctuation token">(</SPAN>self<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="string token">"""Set whether tool is licensed to execute."""</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">return</SPAN> <SPAN class="token boolean">True</SPAN>&nbsp; 
&nbsp; 
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">def</SPAN> <SPAN class="token function">updateParameters</SPAN><SPAN class="punctuation token">(</SPAN>self<SPAN class="punctuation token">,</SPAN> parameters<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>&nbsp; 

&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">if</SPAN> parameters<SPAN class="punctuation token">[</SPAN><SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>altered<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; fields <SPAN class="operator token">=</SPAN> arcpy<SPAN class="punctuation token">.</SPAN>ListFields<SPAN class="punctuation token">(</SPAN>parameters<SPAN class="punctuation token">[</SPAN><SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>value<SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; mylist <SPAN class="operator token">=</SPAN> <SPAN class="punctuation token">[</SPAN><SPAN class="punctuation token">]</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">for</SPAN> field <SPAN class="keyword token">in</SPAN> fields<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; mylist<SPAN class="punctuation token">.</SPAN>append<SPAN class="punctuation token">(</SPAN>field<SPAN class="punctuation token">.</SPAN>name<SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; parameters<SPAN class="punctuation token">[</SPAN><SPAN class="number token">1</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>filters<SPAN class="punctuation token">[</SPAN><SPAN class="number token">1</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>list <SPAN class="operator token">=</SPAN> mylist
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">return</SPAN>&nbsp; 
&nbsp; 
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">def</SPAN> <SPAN class="token function">updateMessages</SPAN><SPAN class="punctuation token">(</SPAN>self<SPAN class="punctuation token">,</SPAN> parameters<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="string token">"""Modify the messages created by internal validation for each tool 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; parameter.&nbsp; This method is called after internal validation."""</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">return</SPAN>&nbsp; 
&nbsp; 
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">def</SPAN> <SPAN class="token function">execute</SPAN><SPAN class="punctuation token">(</SPAN>self<SPAN class="punctuation token">,</SPAN> parameters<SPAN class="punctuation token">,</SPAN> messages<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="string token">"""The source code of the tool."""</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">try</SPAN><SPAN class="punctuation token">:</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="comment token"># Some code to show that I had managed to get what I wanted intot the ValueTable&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; data <SPAN class="operator token">=</SPAN> parameters<SPAN class="punctuation token">[</SPAN><SPAN class="number token">1</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>values
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; arcpy<SPAN class="punctuation token">.</SPAN>AddField_management<SPAN class="punctuation token">(</SPAN>parameters<SPAN class="punctuation token">[</SPAN><SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>value<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"Source"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"TEXT"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"75"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"NULLABLE"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"NON_REQUIRED"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; arcpy<SPAN class="punctuation token">.</SPAN>AddField_management<SPAN class="punctuation token">(</SPAN>parameters<SPAN class="punctuation token">[</SPAN><SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>value<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"DateUpdate"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"DATE"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"NULLABLE"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"NON_REQUIRED"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; arcpy<SPAN class="punctuation token">.</SPAN>AddField_management<SPAN class="punctuation token">(</SPAN>parameters<SPAN class="punctuation token">[</SPAN><SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>value<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"Effective"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"DATE"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"NULLABLE"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"NON_REQUIRED"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; search <SPAN class="operator token">=</SPAN> <SPAN class="string token">'Source'</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">for</SPAN> sublist <SPAN class="keyword token">in</SPAN> data<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">if</SPAN> sublist<SPAN class="punctuation token">[</SPAN><SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN> <SPAN class="operator token">==</SPAN> search<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; final <SPAN class="operator token">=</SPAN> sublist
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; mysource <SPAN class="operator token">=</SPAN> final<SPAN class="punctuation token">[</SPAN><SPAN class="number token">1</SPAN><SPAN class="punctuation token">]</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; sourceData <SPAN class="operator token">=</SPAN> <SPAN class="string token">"["</SPAN> <SPAN class="operator token">+</SPAN> mysource <SPAN class="operator token">+</SPAN> <SPAN class="string token">"]"</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; arcpy<SPAN class="punctuation token">.</SPAN>CalculateField_management<SPAN class="punctuation token">(</SPAN>parameters<SPAN class="punctuation token">[</SPAN><SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>value<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"Source"</SPAN><SPAN class="punctuation token">,</SPAN> sourceData<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"VB"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">""</SPAN><SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">break</SPAN>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">except</SPAN> arcpy<SPAN class="punctuation token">.</SPAN>ExecuteError<SPAN class="punctuation token">:</SPAN>&nbsp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; messages<SPAN class="punctuation token">.</SPAN>addErrorMessage<SPAN class="punctuation token">(</SPAN>arcpy<SPAN class="punctuation token">.</SPAN>GetMessages<SPAN class="punctuation token">(</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">)</SPAN> <SPAN class="line-numbers-rows"><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN></SPAN>

In line 75 I add the "Source" field and in line 84 I try to calculate it, but I get the error that the "Source" field does not exist.

Any help would be appreciated.

Tim

Trouver plus de publications taguées avec

Accepted answers

TimWitt2

In line 84 I replaced parameters[0].value with parameters[0].valueAsText and now it is working. I assume parameters[0].value is the original feature layer without the extra fields and parameters[0].valueAsText grabs the feature layer with the new field.

All comments

JoshuaBixby

And you have verified it gets created, eventually? If you comment out Line 84 and run the script, does the table look the way you expect?

If everything is working as expected and this is simply a matter or timing, a simplistic way to deal with it would be to put a time.sleep() line after the final field addition. You would have to balance sleeping long enough to have the field created and waiting too long so the user gets frustrated.

I would start with the simple approach of inserting time.sleep(10). If the code still errors out than I think that points to something not working quite right with creating the fields.

TimWitt2

Joshua,

thanks for the quick reply. Yes the field is created and when I run the tool again it gets populated. I will have to add a total of 40 fields. That might be enough time for the first field to be available? But I will try the time.sleep approach first.

Thanks,

Tim

TimWitt2

Sadly it didn't work. I have a feeling that I need to somehow update the parameters[0].value before I run the CalculateField.

DanPatterson_Retired

vaguely remember something about using featurelayer vs featureclass and schema being modified which takes time blah blah. It made more sense that this, but I seem to recollect that pairing the creation then the calculation for one field before proceeding on to the next pairing provided the necessary break. Worth a shot

BillFox_0-1635962119633.png

TimWitt2

curtvprice

Thanks for sharing your fix Tim. I think in the case of your layer you are passing, .valueAsText gives you the string label of the layer, which is more likely to play well with the tools and their interactions with the layer in memory.

.valueAsText [GetParameterAsText() for script tools] is (IMHO) the safe way to pass parameters to "go with the flow" how GP is implemented. I only use .value [GetParameter()] to access certain kinds of complex object parameters that are easier to work with directly as objects (value tables come to mind).

Layers are such an odd duck - I wish Esri could have designed this to give us an session-unique integer handle instead of depending on strings that may or not match the layer we want to access. I'm sure there are many historical reasons things are they way the are in arcpy. So you have to be careful with layers.

For code like yours, I make a local layer from the input. If in_fc is a feature class, not a layer, the multiple tools you run on it will run faster because the layer schema (unlike a dataset) are pre-validated, the tool has less to do before it runs, as the data a layer points to is assumed to exist without an additional check. Also the tool parameter validation can ask the (fast) layer in memory whether the field is there without going back to disk (slow) to verify the field there.

in_fc <SPAN class="operator token">=</SPAN> parameters<SPAN class="punctuation token">[</SPAN><SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN><SPAN class="punctuation token">.</SPAN>valueAsText
lyrFC <SPAN class="operator token">=</SPAN> arcpy<SPAN class="punctuation token">.</SPAN>MakeFeatureLayer_management<SPAN class="punctuation token">(</SPAN>in_fc<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"_infc"</SPAN><SPAN class="punctuation token">)</SPAN>
arcpy<SPAN class="punctuation token">.</SPAN>AddField_management<SPAN class="punctuation token">(</SPAN>lyrFC<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"FOO"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"LONG"</SPAN><SPAN class="punctuation token">)</SPAN>
arcpy<SPAN class="punctuation token">.</SPAN>CalculateField_management<SPAN class="punctuation token">(</SPAN>lyrFC<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"FOO"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="operator token">-</SPAN><SPAN class="number token">1</SPAN><SPAN class="punctuation token">)</SPAN>
arcpy<SPAN class="punctuation token">.</SPAN>Delete_management<SPAN class="punctuation token">(</SPAN>lyrFC<SPAN class="punctuation token">)</SPAN> <SPAN class="comment token"># clean up</SPAN><SPAN class="line-numbers-rows"><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN></SPAN>

TimWitt2

Thanks for the hint Curtis, since I will have to do that for 40 fields I am looking for any way to speed up my code.

BillFox_0-1635962498371.png

bharold

arcpy.da.ExtendTable is a way to quickly add fields, below some lines from a tool of mine:

arcpy.CreateFeatureclass_management(outPath,outName,'POINT',
                                    spatial_reference=sR)
narray = numpy.array([], numpy.dtype([('_ID', numpy.int),
                                      ('ResultID',numpy.long),
                                      ('Loc_name','|S23'),
                                      ('Status','|S1'),
                                      ('Score',numpy.double),
                                      ('Match_addr','|S300'),
                                      ('Addr_type','|S50'),
                                      ('AddNum','|S80'),
                                      ('AddNumFrom','|S10'),
                                      ('AddNumTo','|S10'),
                                      ('Side','|S1'),
                                      ('StPreDir','|S20'),
                                      ('StPreType','|S50'),
                                      ('StName','|S100'),
                                      ('StType','|S30'),
                                      ('StDir','|S20'),
                                      ('StAddr','|S300'),
                                      ('Nbrhd','|S80'),
                                      ('City','|S120'),
                                      ('Subregion','|S120'),
                                      ('Region','|S120'),
                                      ('Postal','|S20'),
                                      ('PostalExt','|S70'),
                                      ('Country','|S30'),
                                      ('LangCode','|S10'),
                                      ('Distance',numpy.double),
                                      ('X',numpy.double),
                                      ('Y',numpy.double),
                                      ('DisplayX',numpy.double),
                                      ('DisplayY',numpy.double),
                                      ('Xmin',numpy.double),
                                      ('Xmax',numpy.double),
                                      ('Ymin',numpy.double),
                                      ('Ymax',numpy.double)]))
arcpy.da.ExtendTable(outFC,arcpy.Describe(outFC).OIDFieldName,narray,"_ID")
arcpy.AlterField_management(outFC,'Nbrhd',new_field_alias='Neighborhood')

curtvprice

You're welcome!

I will have to do that for 40 fields I am looking for any way to speed up my code.

Given your application (it sounds like you need to populate these fields from existing fields with different names, maybe parts of field content too), you may want to consider setting up a field map, add your 40 fields to it, and running Feature Class To Feature Class. Field maps are a bit tricky to work with but I'm certain this is the fastest way to add 40 fields to a table and copy content over from existing fields.

That ExtendTable thing is awesome though!

Rejoindre la conversation

Les membres connectés peuvent publier, suivre les mises à jour, et plus encore. Nouveau ici ? Inscrivez-vous gratuitement.

Liens rapides

Community Help
Find useful guides, FAQs, and documents to help you navigate and make the most of Esri Community.