Move polyline endpoints using field calculator?

AZumwalt

How do I go about moving the endpoint of a polyline using field calculator? I have the x,y end point coordinates in the "X" and "Y" fields. 

def XYsetVALUE(shape, X_value, Y_value):
point = shape.getPart(1)
point.X = X_value
point.Y = Y_value
return point

SHAPE = XYsetVALUE ( !SHAPE!, !X!, !Y!)

XanderBakker

The fact that a polyline disappears when the Z value is invalid is behavior that I have seen before (recently also with ArcGIS Pro). I assume that the geometry is considered not to be valid. 

So you could follow the advise of Joshua Bixby and use the cursor. Always test this on a copy to avoid loosing data, since that data is modified.

Here is a snippet of code that you could try. It will not process multipart polylines nor elements that have an invalid Z:

<SPAN class="keyword token">def</SPAN> <SPAN class="token function">main</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">import</SPAN> arcpy

&nbsp;&nbsp;&nbsp; fc <SPAN class="operator token">=</SPAN> r<SPAN class="string token">"path to a copy of your polyline features"</SPAN>
&nbsp;&nbsp;&nbsp; fld_x <SPAN class="operator token">=</SPAN> <SPAN class="string token">"X"</SPAN>
&nbsp;&nbsp;&nbsp; fld_y <SPAN class="operator token">=</SPAN> <SPAN class="string token">"Y"</SPAN>
&nbsp;&nbsp;&nbsp; fld_z <SPAN class="operator token">=</SPAN> <SPAN class="string token">"Z"</SPAN>

&nbsp;&nbsp;&nbsp; flds <SPAN class="operator token">=</SPAN> <SPAN class="punctuation token">(</SPAN><SPAN class="string token">'SHAPE@'</SPAN><SPAN class="punctuation token">,</SPAN> fld_x<SPAN class="punctuation token">,</SPAN> fld_y<SPAN class="punctuation token">,</SPAN> fld_z<SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">with</SPAN> arcpy<SPAN class="punctuation token">.</SPAN>da<SPAN class="punctuation token">.</SPAN>UpdateCursor<SPAN class="punctuation token">(</SPAN>fc<SPAN class="punctuation token">,</SPAN> flds<SPAN class="punctuation token">)</SPAN> <SPAN class="keyword token">as</SPAN> curs<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">for</SPAN> row <SPAN class="keyword token">in</SPAN> curs<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; polyline <SPAN class="operator token">=</SPAN> row<SPAN class="punctuation token">[</SPAN><SPAN class="number token">0</SPAN><SPAN class="punctuation token">]</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; x <SPAN class="operator token">=</SPAN> row<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; y <SPAN class="operator token">=</SPAN> row<SPAN class="punctuation token">[</SPAN><SPAN class="number token">2</SPAN><SPAN class="punctuation token">]</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; z <SPAN class="operator token">=</SPAN> row<SPAN class="punctuation token">[</SPAN><SPAN class="number token">3</SPAN><SPAN class="punctuation token">]</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; polyline <SPAN class="operator token">=</SPAN> SetLastPointPolyline<SPAN class="punctuation token">(</SPAN>polyline<SPAN class="punctuation token">,</SPAN> x<SPAN class="punctuation token">,</SPAN> y<SPAN class="punctuation token">,</SPAN> z<SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; curs<SPAN class="punctuation token">.</SPAN>updateRow<SPAN class="punctuation token">(</SPAN><SPAN class="punctuation token">(</SPAN>polyline<SPAN class="punctuation token">,</SPAN> x<SPAN class="punctuation token">,</SPAN> y<SPAN class="punctuation token">,</SPAN> z<SPAN class="punctuation token">,</SPAN> <SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">)</SPAN>


<SPAN class="keyword token">def</SPAN> <SPAN class="token function">SetLastPointPolyline</SPAN><SPAN class="punctuation token">(</SPAN>polyline<SPAN class="punctuation token">,</SPAN> x<SPAN class="punctuation token">,</SPAN> y<SPAN class="punctuation token">,</SPAN> z<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="comment token"># BEWARE: it will not change multipart polylines or items with Z is None</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">if</SPAN> polyline<SPAN class="punctuation token">.</SPAN>isMultipart <SPAN class="operator token">==</SPAN> <SPAN class="token boolean">True</SPAN><SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">return</SPAN> polyline
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">elif</SPAN> z <SPAN class="operator token">==</SPAN> None<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">return</SPAN> polyline
&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">else</SPAN><SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; sr <SPAN class="operator token">=</SPAN> polyline<SPAN class="punctuation token">.</SPAN>spatialReference
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; lst_pnts <SPAN class="operator token">=</SPAN> <SPAN class="punctuation token">[</SPAN><SPAN class="punctuation token">]</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">for</SPAN> part <SPAN class="keyword token">in</SPAN> polyline<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">for</SPAN> pnt <SPAN class="keyword token">in</SPAN> part<SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; lst_pnts<SPAN class="punctuation token">.</SPAN>append<SPAN class="punctuation token">(</SPAN>pnt<SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; pnt_z <SPAN class="operator token">=</SPAN> arcpy<SPAN class="punctuation token">.</SPAN>Point<SPAN class="punctuation token">(</SPAN>x<SPAN class="punctuation token">,</SPAN> y<SPAN class="punctuation token">,</SPAN> z<SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">print</SPAN> lst_pnts
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; lst_pnts<SPAN class="punctuation token">[</SPAN><SPAN class="operator token">-</SPAN><SPAN class="number token">1</SPAN><SPAN class="punctuation token">]</SPAN> <SPAN class="operator token">=</SPAN> pnt_z
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">print</SPAN> lst_pnts
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; polyline <SPAN class="operator token">=</SPAN> arcpy<SPAN class="punctuation token">.</SPAN>Polyline<SPAN class="punctuation token">(</SPAN>arcpy<SPAN class="punctuation token">.</SPAN>Array<SPAN class="punctuation token">(</SPAN>lst_pnts<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">,</SPAN> sr<SPAN class="punctuation token">,</SPAN> <SPAN class="token boolean">True</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="token boolean">False</SPAN><SPAN class="punctuation token">)</SPAN>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <SPAN class="keyword token">return</SPAN> polyline

<SPAN class="keyword token">if</SPAN> __name__ <SPAN class="operator token">==</SPAN> <SPAN class="string token">'__main__'</SPAN><SPAN class="punctuation token">:</SPAN>
&nbsp;&nbsp;&nbsp; main<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>

The code is not tested. If you are able to share a part of your data I can test it.