topic Re: Map for each row in a shapefile with Python in Python Questions

Map for each row in a shapefile with Python

MarcoPignatiello — Fri, 15 May 2020 17:19:17 GMT

Hi, I would like to know if it's possible to create in Python a script which for each record (row) in a shapefile (TYPE:point), the script return a map with the single point. I know how exporting maps with shapefile's points all showed, but I would like to see in each map only one point for time. I tried to do a script with definition query inside a for cycle but it didn't work!

Re: Map for each row in a shapefile with Python

DavidPike — Sun, 17 May 2020 10:28:48 GMT

not python but could DDP be used? How To: Hide features in Data Driven Pages so only the feature of interest is visible

Re: Map for each row in a shapefile with Python

MarcoPignatiello — Mon, 18 May 2020 15:53:40 GMT

Thanks for your answer. I have this shapefile and I would like to see n maps with only 1 point for each map. I try with DDT script and it renturns me n maps but with all points in each. The question is: Is it possible to do an iterete definition query based on the Field (FID)?? this field is a numerical field so I think it would be possible to do a for loop setting first FID=0, then FID=1.etc.. but I don't know how I can do it.

Thank you for your help!

Re: Map for each row in a shapefile with Python

DavidPike — Mon, 18 May 2020 16:10:12 GMT

I don't think the index field can be a number, maybe add a new field and copy the number as a string?

what does your script look like?

Re: Map for each row in a shapefile with Python

MarcoPignatiello — Tue, 19 May 2020 07:09:04 GMT

#Set variable

shp=arcpy.mapping.Layer(r"C:\Users\Utente\Dropbox (Geomatica_DSFTA)\Admin (L)\Amiata_Via_Remedi\GIS\shp\Elementi_20200508_v2.shp")

#Enable DDP and do this for loop

for pageNum in range(1, mxd.dataDrivenPages.pageCount + 1):
mxd.dataDrivenPages.currentPageID = pageNum

#I thought with to create a loop like this but it doesnt work. For sure this is not the correct way to do it

for a in range (1,174):
shp.definitionQuery='"NUM"='"a"

arcpy.mapping.ExportToPNG(mxd, r"C:\Users\Utente\Desktop\OUTPUT\map” + str(pageNum) + ".png")
del mxd

Re: Map for each row in a shapefile with Python

DavidPike — Tue, 19 May 2020 07:18:10 GMT

The loop certainly looks wrong, why the 2 assignment operators? looks to be in the wrong place but can't tell the indentation.

please refer to Dan Patterson‌ 's code formatting guide /blogs/dan_patterson/2016/08/14/script-formatting

Re: Map for each row in a shapefile with Python

MarcoPignatiello — Sat, 11 Dec 2021 11:05:40 GMT

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

#Set variable
shp=arcpy.mapping.Layer(r"C:\Users\Utente\Dropbox (Geomatica_DSFTA)\Admin (L)\Amiata_Via_Remedi\GIS\shp\Elementi_20200508_v2.shp")

#Enable DDP and do this for loop
for pageNum in range(1, mxd.dataDrivenPages.pageCount + 1):
	mxd.dataDrivenPages.currentPageID = pageNum

#I thought with to create a loop like this but it doesnt work. For sure this is not the correct way to do it
	for a in range (1,174):
		shp.definitionQuery='"NUM"='"a"
	
arcpy.mapping.ExportToPNG(mxd, r"C:\Users\Utente\Desktop\OUTPUT\map” + str(pageNum) + ".png")
del mxd‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

NUM= Field of shapefile, TYPE: short integer, from 0 to 174

I assign 2 assignment operators (shp.definitionQuery='"NUM"='"a") because I want 174 maps where in the first map show only the point that corrisponding a NUM=1, then I want the same thing but NUM=2 till the end NUM=174. I dont know if its possible, I'm a beginner as a "programmer"