A layer is a collection of information. It contains specific elements of a gis in a specific presentation method (e.g raster or vector layer). Layers can be edited separately in order to create individual toppics for a map.

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2k views

Leaflet add and remove legends with layer selection

I'm new to Leaflet/Javascript and have been struggling to get legends a map to show only when a specific layer is selected from the layer control. I have three layers, one of which I would like to ...
3
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1answer
2k views

How to select only polygons that overlap with another layer?

I have two shapefile layers created from different thresholds from a predictive model (Pink=80; Yellow=95). Is there a way to create a new layer of only those pink polygons that contain yellow ...
3
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1answer
62 views

qgis2 - hide a layer (or its labels) when another layer is coincident?

I have two road layers - one is a subset of the other, so, there's a lot of overlap. When they are coincident, I see labels from both layers. The 'lower' layer is the thin line road in the SW ...
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2answers
598 views

GeoExplorer: “Could not create layer record for layer group”

I installed GeoServer via OpenGeo Suite, and still working on it. I created a "Layer Group" and add layers from local PostGIS. I tried to preview it from "Layer Preview" and show perfectly through ...
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1answer
1k views

Can one convert text annotations to a layer in Qgis?

I know text annotations can be turned on & off with Ctrl+T... but is there any way to export them as a layer? Thanks!
3
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1answer
243 views

Performing a field calculation affects selectable layers in ArcGIS 10.1

In ArcMap 10.1 I have a table open for a layer that I have set as not selectable. Yet when I use the Field Calculator for a record(s) in that table, it automatically makes the associated layer a ...
3
votes
1answer
218 views

definition query and mosaic dataset from gdb ArcMap 10.1 SP1

I have a Python AddIn Combobox to select a value from the drop-down list. This value changes the definition query of the layers in mxd. This works fine for "normal" feature classes, not for a mosaic ...
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2answers
2k views

How to make the Overlays section in an OpenLayers LayerSwitcher exclusive?

At the simplest level I need to figure out how to create a customized OpenLayers LayerSwitcher Overlays section which is not using Checkboxes, but uses RadioButtons instead. For my application its ...
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2answers
4k views

Load layers only when zoom level is reached

I'm trying to load different layers based on the user zoom level with OpenLayers. I've seen some similar questions in here, but they load the layer and then hide/show it based on the zoom level. I ...
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2answers
3k views

How to remove layers of detail from an osm file?

I want to remove some layers from the osm map of an area. It has all the details like POI, offline routing and all. But I just want the map data. How can I remove this extra layer from the map?
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0answers
32 views

PyQGIS select layer by original table name

As far as I see, on QgsMapLayerRegistry.instance() there is a method to select layers: mapLayersByName(Qstring) and the method mapLayer(QString) respectively, wich accesses a layer by its id. ...
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1answer
89 views

Writing a custom function in QGIS to rank features

I have written the following custom function in python for QGIS, cobbled together from various sources. The aim is to use it in the expression editor to return the rank of each feature based on the ...
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0answers
31 views

gdal_translate multiple GDAL_PDF_LAYERS_OFF entries gives error

The documentation says that GDAL_PDF_LAYERS_OFF takes a list of comma separated layers. Examples look just like what I am trying to do. Executing the following gives an error FAILURE: Too many ...
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0answers
15 views

Problem Importing CAD features using arcpy.MakeFeatureLayer_management?

When importing multiple CAD drawings using "arcpy.MakeFeatureLayer_management" and "arcpy.Merge_management" I encountered a problem. Drawings that have line weights and elevation values assigned to ...
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0answers
36 views

OpenLayers WFS Multipoint

I am modifying a OpenLayers setup which uses WFS capabilities to create a vectorLayer on a map to support multipoints. GeoServer is setup to send points and multipoints however only points are ...
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0answers
118 views

Sourcing free live traffic layers to use in MXD of ArcGIS Desktop?

I am looking for free live traffic layers for an ArcGIS Desktop 9.3 MXD. My searches haven't been that successful.
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0answers
385 views

Batch export to shapefile by attribute field in QGIS

I have a project in QGIS where I am creating a map of plants over a large area. I want to take the "Genus" field (of which there are 100 hundred values) and essentially create 100 shapefiles based on ...
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108 views

Layer tick boxes embedded in PDF map

Maybe this is more of a PDF question than a GIS question. Today, I received a layered PDF map shown as a landscape A3, with a square map on the left, and with the map title, the legend, the scale, a ...
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0answers
503 views

How to load the default layer style from Postgresql with Python?

I would like to write a python macro that upon opening my QGIS project file will reload the default style for each layer from the postgres 'layer_style' table. I have had a look at the documentation ...
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0answers
390 views

Getting layers from SDE with vba

Im running arcmap 9.1. i have the code that lists feature classes in a list box from the SDE. The users select from one list box and adds it to another list box. How do i get it to show the layer name ...
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0answers
440 views

calculate total Miles in a polygon using Google Map

I have an application that allows the users to create any custom polygon layer on top of google maps, i am interested to know if their is a way to select the road layer in this polygon and then ...
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0answers
696 views

Add CAD Drawing Dataset into ArcMap using Python

I am trying to add an CAD Drawing Dataset into ArcMap using Python. Question is how to add a Auto-CAD .dwg file to ArcMap using Python Normally comes in as CAD file within a Group layer with: ...
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1answer
298 views

Repairing disconnected layers with selection sets using ArcObjects?

Has anyone had any success of repairing disconnected layers that have selection sets that have their data sources broken in ArcGIS? Is there a way to detect this through code and then re-create that ...
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5answers
5k views

Is there any way to extract coordinates of a road segment using QGIS?

I add my own road vector data on top of Google map using open layers plugin with QGIS. The vector layer is generated using PostgreSQL DB. Is there any way to extract coordinates of a road segment ?
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2answers
54 views

Using QGIS shapefile layer in ArcMap project?

I created a QGIS shapefile layer in QGIS that I want to give to a friend of mine for his ArcMap project. Will he be able to open and use my work?
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votes
1answer
1k views

QGIS identify features button issue

Is there anyway to get the Identify Features button in QGIS to automatically select a layer and provide the information without having to highlight it first in the layers TOC? MapInfo and ArcGIS ...
2
votes
1answer
868 views

QGIS/PostGIS layer styles

I've made a plugin asking for login credentials to a DB. Once logged in, the plugin is loading some layers from the DB. In the DB there are both admin and "normal" users. I've saved two styles to the ...
2
votes
1answer
86 views

Virtual fields are lost when duplicate layers

I've just upgraded to QGIS 2.12.3 - and hoped that the issue which was really time-consuming in 2.12. <3 could have been solved ... On duplicating layer - with tons of joined tables and virtual ...
2
votes
2answers
157 views

How do I find a layer based on source name using ArcObjects?

I am relatively new at creating tools with ArcObjects and I am having trouble finding a layer based on the layer's source name by looping through all layers. I've seen here that it is possible, but I ...
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2answers
374 views

Creating sub sections (groups) of layers in QGIS?

I am working on a project regarding Fish species and fishing methods with many layers. This creates confusion. I would like to create layer sub sections (groups) like the following: Fish Species ...
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2answers
2k views

How to export all the layers from Table of Content to shp file?

I have got lots of different layers in the Table of Content panel in ArcMap. I want to export them all in shp format in one go. How can I do that? So far I have been doing it one by one by right ...
2
votes
1answer
331 views

Why is shapefile not drawing in expected location after (or before) using Define Projection tool? [duplicate]

I have downloaded this zipped shapefile of bus routes from the City of Houston data portal. I then performed these steps in ArcGIS Desktop 9.3.1: Extracted the shapefile from the *.zip Added this ...
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1answer
2k views

How to zoom to the extent of Qgsvectolayer qgis?

Anyone know how to zoom to the extent of a Vectorlayer in qgis using python plugin?
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votes
2answers
716 views

Managing a large number of layers in OpenLayers/GeoExt and Geoserver

I am building a web application to facilitate the handling of approximately 2500+ historic maps. I think it would be too difficult for our users to search for specific maps in an ordinary layer tree. ...
2
votes
2answers
131 views

AttributeError: 'Layer' object has no attribute 'listLayers'

I want to use the result of OD cost matrix for my further calculations. However, whne I try to extract the sublayer "lines" it returnes an error AttributeError: 'Layer' object has no attribute '...
2
votes
1answer
85 views

Arcpy Code result- “NaN”

When i run this code (in arcView 10.3) in order to check the data frame extent, i received "NaN NaN" result with the exact data frame. I don't understand why python print this out? I checked in http://...
2
votes
2answers
69 views

Update a group layer using arcpy

I work with several MXD'S and i try to update a group layer named "allHa" containing several layers with this code: import arcpy,os,sys,string import arcpy.mapping from arcpy import env env....
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2answers
102 views

How to remove all transparency from all layers?

I am using ArcMap 10.1 and I would like to remove all transparency from all the layers in the map at once.
2
votes
1answer
596 views

Standalone Python script to split a polyline with a point layer

I have a polyline layer and a layer of points that are on top of the polylines. I do not have the ArcGis advanced license so I can't use the Split Line at Point tool. Can someone help me with a ...
2
votes
1answer
985 views

How to copy single polygon and paste multiple times to same layer in Arcmap 10?

I'm attempting to copy a single polygon and paste it 113 times to make "parcels" for a condominium building.
2
votes
2answers
625 views

How to load layers from postgis to dotspatial or sharemap viewer

I want to develop a PostGIS viewer for PostgreSQL (with SQL query editor) to visualize PostGIS layers. Which spatial library (.net C# supported) do I have to use?
2
votes
2answers
738 views

Save a layer for each unique value using Python in QGIS

I have a map, in which each region is defined as an attribute of the map (I can select each region from the attribute table). I am trying to create new layers each one containing only 1 region using ...
2
votes
1answer
182 views

How to add Checkboxes in Geoserver

I have a POI table with some data of categories like Airport,ATM,Bank etc. I want to show these categories as checkbox so that if I click in the ATM Checkbox, only the ATM Points will be display. Is ...
2
votes
1answer
81 views

Issues with toggling layers with mapbox.js

I am having issues with toggling map layers with mapbox.js. Using the code from [https://www.mapbox.com/mapbox.js/example/v1.0.0/layers/] it pulls the basic mapbox base maps ex. mapbox.outdoors or ...
2
votes
1answer
26 views

Switch layer when zooming

I'm wondering if it is possible to set up a boundary on zooming for e.g. 3 different vector layers, so that when zooming in QGIS will automatically switch layer? For example layer 1 has scale 1:...
2
votes
1answer
35 views

How to display street names from OS StreetAny layer?

Using QGIS version 2.10.1-Pisa. I have imported layers from an Ordnance Survey data set. I have a layer called 'Street any' which gives me the boundaries of the streets which I can see. I can see ...
2
votes
2answers
173 views

definition query with 3 plus variables to loop with python and save layer files

I have a script that takes an input feature class and uses a field within this class to create a definition query for each unique field. A question on how to do this is listed below saving layers for ...
2
votes
1answer
144 views

PyQGIS: How to get the list of valid layers in TOC?

To get the list of TOC layer names I used the approach suggested here: for layer in QgsMapLayerRegistry.instance().mapLayers().values(): print layer.name() But this method is not reliable due ...
2
votes
1answer
86 views

Replacing layer ArcSDE connection

I am very new to using Python... I have an MXD with all of my layer files in it. They are grouped by category etc. Each layer file references a dataset within my SDE. My SDE has two different ...
2
votes
3answers
72 views

Saving extent of satellite imagery in ArcGIS Desktop?

I'm using 50cm imagery for the whole country of South Africa, which make zooming and panning painfully slow. Can I save imagery for just the area I am working with (ie. data frame, city, province)? I'...