A sequence of instructions that repeats either a specified number of times or until a particular condition is met.

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1answer
33 views

Create a table with open() in a loop using the SearchCursor and InsertCursor

I like to create a table with open() in a loop using the SearchCursor and InsertCursor, but I don't know how. Before I used a few geoprocessing tools to get a field for percent. The Attributtable of ...
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0answers
37 views

Python + GME (Spatial Ecology) + Subprocess.call

I'm trying to run the following code to use GME commands in Python. import arcpy,os,subprocess from arcpy import env env.workspace=r"D:\Users\myname\Desktop\aviso" count=0 for raster in (f for f in ...
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3answers
113 views

Loop with arcpy.ListFiles

I'm super new on here and have also not much experience with Python but I really like to learn to work with this language. I'm tying to write a script for this: I think I need a for loop instead ...
2
votes
1answer
32 views

How to do loops on raster cells with python console in QGIS?

I'm new here and beginner with python. I'm looking for a solution to my problem for some hours but now you are my last chance... I'm using the python (2.7.5) console in QGIS (2.4.0). Is there a ...
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3answers
44 views

Loop in ModelBuilder for compositing bands of multiple Images

I'm attempting to automate the "Composite Bands" tool somehow in ModelBuilder, but haven't been able to figure out an effective method. I have landsat 7 data that is separated into folders and each ...
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1answer
51 views

Getting error 'exceptions.NameError' in Python script?

I'm getting <type 'exceptions.NameError'>: name 'B' is not defined when I run this script. Why is my 'B' not defined and is it a syntax error? For clarification, I am trying to get the code to ...
2
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1answer
62 views

forLoop & joinField & different names

I have a folder with an output (shapefiles) from an iteration. On this output, I want to perform a join between two attributetables. So far so good. Here comes the tricky part. There are different ...
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2answers
58 views

Call field from zip() into Field Calculator expression ArcGIS

I've been trying to find a way to call in field names from a zip(). Basically I have 12 fields called "Flw_days1", "Flw_days2" etc and corresponding "Depth" fields that need to be calculated using the ...
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1answer
20 views

Interaction with two variables as parameters, saving the raster properties output into a table (.dbf)

The draft of the model below TASK: I need to calculate the percentage of river channel that is covered with shadow in each timestep RESOURCS: I have values for azimuth and elevation of the sun ...
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1answer
34 views

excluding NaN records from FOR loop?

I am trying to create an array of Z and M values for vertices from a polyline (Z and M enabled) feature class. Some of the vertices do no have M values/geometry and I wish to exclude them from the ...
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27 views

How can I define coordinate system of feature class when overlaying with coordinate zone shapes in python?

I have generated bounding boxes for CAD drawings that do not have defined coordinate system files. I know that each drawing could be in one of 6 different systems that do not overlap. My idea was to ...
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1answer
27 views

Creating a loop for Lines data (spatial data)

I am trying to build a lines shapefile with the contour lines from the 20 meters isobath from along the East African coast. This contour line of 20 meters has different segments and I have this ...
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1answer
45 views

Splitting the job on Arcpy SearchCursor

I'm running a for loop with a cursor to disaggregate a large feature class into many smaller ones (of one polygon each). ArcMap crashes after about 1100 iterations, and I am trying to break the job ...
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2answers
41 views

If clause within if clause VBA Arcgis10

I'm using ArcGIS10. I do not know what's wrong with this VBA code in the Field Calculator: *All the fields are String type If [StartY] < [EndY] Then If [DOT_OSM] ="1" Then Output = "F" ...
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0answers
31 views

Assigning a changing value to a variable in ArcMap using Python

I have two lists/strings/sets (the exact format can easily be changed) of values (u and v). I would like to do a cost distance analysis between each point in u and all points in v. For this, I need to ...
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0answers
15 views

extracting values from maps and inserting into a summary table

I have several maps that I am working with. I want to extract the values (1, 0 and NA) from the maps and place them all into a summary matrix. Since I have so many maps, I think its best to do this as ...
2
votes
2answers
114 views

Nested loops for raster calculation arcpy

I am trying to figure out a way to input corresponding raster datasets from two separate folders into an equation using arcpy. I think it requires some sort of nested loop but I can't figure out how ...
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2answers
31 views

GRASS GIS using a loop with r.neighbors command

I'd like to do a trend analysis with ndvi data from 1982 til 2005. I am using the r.neighbors command to get first the spatial variance (then I would use r.series method=slope to get the actual trend) ...
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0answers
33 views

How to crop an image into more than 80 small sections automatically in R

I'd like to crop an image into 15 sections in R. The image projection is Geog lat/long, extending 87 to 120 degree in East and 45 to 55 degree in North. I want to separate it by every 2 degree. So I ...
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1answer
42 views

How to loop qgis:zonalstatistics using Python?

I'm looking for some Python + QGIS foo for the following: import processing for i in range (1,20): processing.runalg("qgis:zonalstatistics", "/folder/input/raster.tif",%i, ...
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1answer
38 views

Scripting a Loop of Clip (Analysis)

I wish to loop function that clips a shapefile by a feature class. I want to make the clip the same as the input name. The names of the files are WVHGT_201403281200_f180_201404050000.shp and I just ...
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1answer
52 views

MapBasic For Loop ignoring every other row

I have made a loop in MapBasic but is it only updating every other row in the table: My code works from the bottom of the table upwards to generate start and end coordinates for polyline features: ...
3
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1answer
50 views

Keeping the Highest Valued polygon

I have a single polygon feature class that contains large polygons which represent signal strength. Often times these polygons overlap. I dissolve to get multi-part polygons with a value range of 3 ...
2
votes
1answer
82 views

Map algebra for loop

I have never coded in Python before and I am trying to loop a simple map algebra equation across 365 rasters. I am trying to calculate total water flow over cells but in the raster I have a negative ...
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1answer
46 views

Using MakeFeatureLayer to select by location in arcpy

I'm trying to assign a state plane zone based on if a point intersects it. I make a feature layer from a feature class. It gets through the loop once and calculates everything correctly, but when it ...
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1answer
332 views

How to create a loop in R to average ndvi raster time series?

I have monthly ndvi raster geotiffs for multiple years. I need to run a loop to get the average of each of these ndvi grids/rasters. Each of my ndvi rasters contains 143 pixels. I would like the ...
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vote
1answer
152 views

Multiply a raster list with a field value list in a FOR loop in ArcPy

I'm trying to create a simple map algebra calculation not managed by ModelBuilder, but writing it in Python is trickier than I thought. I have a list of raster in a GDB and I must multiply them by ...
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1answer
125 views

How to create a loop for multiple points with cost distance / cost path in ArcGIS 10.2 in python

I would like to know how to simplify the following code in order to execute it more efficiently than copy paste 82 processes (with a loop I guess?) but I don't know how to do it. There are 4 main ...
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1answer
214 views

Out of memory when calculating loop in ArcGIS 10.2 with Python 2.7

I am quite new to scripting for ArcGIS, so don't mind the styling and layout. I am trying to calculate 600.000 routes by looping a network analyst route analysis. The script extracts two pointID's ...
1
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1answer
241 views

add unique IDs to mutiple polygons using loop or apply function

I want to add a unique ID (row number) for each polygon in a SpatialPolygonsDataFrame. I'm new at working with spatial data (and programming) so bear with me please. The goal is to merge all polygons ...
2
votes
1answer
72 views

Mystery duplicate values

I'm using a unique list to populate up to 10 fields for a fc with correct geometry, in an "overloading" manner as you would in excel. I noticed on my first run through I had an "index out of range" ...
0
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1answer
112 views

R for loops in Geospatial modelling environment

I am using the isectpolypoly command in GME and would like to iterate over several polygons ("proj_0_ect0207", "proj_1_ect0207"). My code is as follows: for (i in 0:30) { ...
2
votes
2answers
151 views

Error when looping Polygon to Raster with python through different fields ArcGIS 10

This is the first time I have posted a question on here so please have some patience! I've been trying to create a python script to loop through numerous shapefiles converting various fields to raster ...
2
votes
2answers
91 views

Python-OGR: nested loop only loops once

I have a polygon file buffer_stands.shp with 20 features and I have a line file OSMroads.geojson with 9 features. I expected the script to loop through the buffers and print out for each buffer loop ...
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2answers
395 views

How to access each raster in a stack with a loop

I have a stack of rasters and I want to access each layer, combine each later with another file and finally export the resulting file as a csv file. Is there any way to do this with a loop? So far I ...
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1answer
574 views

How to loop through all columns in a table/layer getting all data for a row/feature in MapBasic?

I'm trying to extend this GNU-licensed plugin MI2SVG, which converts MapInfo maps to SVG, so that it writes associated table data into the SVG it creates, so that browser based JS web applications can ...
3
votes
2answers
182 views

arcpy.SearchCursor loops one time but then does not repeat

The part of the script I'm having trouble with is the arcpy.SearchCursor. The cursor runs 1x and then does not re-run. The goal was to re-retrieve the field value and apply it to the image layout. It ...
2
votes
3answers
255 views

ArcPy nested loop problem

I have a question connected with ArcPy. I was trying to make a nested loop with 2 cursors - 1st with 2 elements and 2nd with 5 elements. The statement should return 10 connections, e.g. 1-1, 1-2, ... ...
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2answers
832 views

How to loop through a list of shapefiles and rename them?

I am trying to upgrade a simple script to list all shapefiles in a folder and if necessary in any folders within and then loop through the list of shapefiles and rename them. import arcpy # Set ...
0
votes
2answers
182 views

Python Delete point in a distance of x meters

I took this code from this source Select maximum number of points more than x meters apart It seems to work for other users, but for me it's an endless loop. I do not understand why, though the code ...
2
votes
1answer
136 views

Stumped on python looping and data dictionaries

I have been stumped getting my python code to work for a while now. I've been using python for the last several years on and off for simple things, but I am far from an expert in python. I am trying ...
4
votes
1answer
248 views

Python - ArcMap: Fastest method to loop over Mxd's

I am attempting to find the fastest method for looping over multiple map documents while keeping memory resources down. I'm running this script outside of Arcmap 10. I have 5 map documents which are ...
1
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1answer
85 views

PostGIS integer loop

PostGIS is very new to me, and I'm having difficulty performing an operation that probably isn't too difficult. I have vector layers each filled with the outline of a landmass through time. I want to ...
0
votes
1answer
838 views

While looping with arcpy: ERROR 010240: Could not save raster dataset

Hi I am very new to python coding and have been struggling with this for a while I cannot see the reason for this error! Any help will be greatly appreciated. Here is the code that is causing this ...
0
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1answer
663 views

Loop over features of a GeoJSON object from CartoDB

I have just little knowledge about HTML and JavaScript. Nevertheless I was playing, copying and pasting around with Leaflet and CartoDB. I want to display the features GeoJson in a table. This is ...
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1answer
171 views

how to loop grass command in python and put variable in output file

anyone, first day Grass programming with python scripting; first prob; simple I want to reclass the same raster several times; and save the file with the value loop variable at the end ... can not ...
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3answers
973 views

Create Text files from a loop with Python? [closed]

I need to create some files to hyperlink to from Arcmap. I have a folder of jpeg files (100.jpg, 101.jpg etc...). I need to loop through them and create a text file of the same name except replace the ...
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2answers
138 views

How to interact layers with a nested loop?

I've dealing with the code below with such a long time. I have to show in a raster image the result of calculating the cost of the electricity for a solar plant. The thing is that I have to interact a ...
2
votes
1answer
156 views

Updating and inserting a field within the same loop

I am working with an empty feature class where I am writing a script to create polylines within the featureclass and attach an associated text value with the polyline. I am using a for loop as noted ...
0
votes
1answer
270 views

Stop a Cursor loop when only 1 item is selected with Python

I am trying to create a Cursor that goes through a selection process and stops looping when only one feature is selected. Basically, as the Cursor loops it subsets a selection, and instead of going ...