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.

learn more… | top users | synonyms (1)

3
votes
0answers
352 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 ...
3
votes
0answers
97 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 ...
3
votes
0answers
474 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 ...
3
votes
0answers
377 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 ...
3
votes
0answers
419 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 ...
3
votes
1answer
292 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 ...
2
votes
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 ?
2
votes
2answers
41 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?
2
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
773 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
79 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
130 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 ...
2
votes
2answers
302 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 ...
2
votes
2answers
1k 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
312 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 ...
2
votes
1answer
1k 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?
2
votes
2answers
703 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
1answer
78 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 ...
2
votes
2answers
61 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 ...
2
votes
2answers
77 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
888 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
585 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
670 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
176 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
66 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
2answers
96 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
25 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 ...
2
votes
1answer
33 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
1answer
493 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
2answers
157 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
111 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
78 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
68 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)? ...
2
votes
1answer
621 views

How to add label to QgsVectorLayer by Python

my goal is to define label programmaticly for the case similar for the figure below: But didn't find any guidance how to do so using Python. I have a feeling it could be done using QgsLabel but ...
2
votes
2answers
662 views

Add multiple Layer files in subdirectories to mxd using python

I have more than 300 layer files located in many sub-Folders and sub-sub-Folders. All Sub Folders are located in one large directory.I read Use python to add layers to TOC and I try, with arcpy, to ...
2
votes
1answer
198 views

Is the MakeFeatureLayer temporary location the same as “in_memory”? [duplicate]

From the ArcGIS Desktop Help: The layer that is created by the tool is temporary and will not persist after the session ends unless the layer is saved to disk or the map document is saved. ...
2
votes
2answers
1k views

Creating New Layer After Sorting Attribute Table using QGIS?

I have been self-teaching myself some open source GIS. I downloaded QGIS and have been following this four part tutorial - ...
2
votes
2answers
932 views

How does Leaflet layer ordering work with CartoDB layers?

All, I'm trying to figure out how Leaflet layer ordering works when you have layers coming from CartoDB. I have a map with 1 polygon layer (cartodb), 3 point layers (cartodb), 1 basemap layer ...
2
votes
1answer
317 views

How to convert format and CRS of many shapefiles to kml (or csv, json..)?

I tried to use QGIS to transform shp files in kml and to translate the CRS to use in a google maps application. My problem is that I have a lot of shp files that i can open in a bulk manner by drag ...
2
votes
1answer
609 views

Can I Turn Off or Remove Map Layers in QGIS Print Composer

The title pretty much says it all. I have a base map in QGIS that I am using with several Print Composers. In one of the Print Composers, I don't want one of the layers to show up. Is there any way ...
2
votes
2answers
5k views

How to clip a layer file

I have a world imagery layer that I want to clip to a single county. I would just save as a JPEG and edit using other software, but this uses a lot of processing power if I want a high resolution. I ...
2
votes
1answer
459 views

How to realign (PostGIS) layers in QGIS?

I'm trying to realign layers in QGIS. As you can see here, the "background" light-blue layer is not aligned with the top layers. I'm working with pgAdmin III and importing PostGIS Layers in QGIS. My ...
2
votes
1answer
938 views

How to use arcpy.mapping to batch export layer to KML?

I am trying to export map layers from an MXD to KML using arcpy with the following code: import arcpy, os, sys, traceback arcpy.env.overwriteOutput = True mxd = ...
2
votes
1answer
1k views

Create new polygon layers from postcodes latitude & longitude

First at all, I want to say that I am geocoding enthusiastic but have no formal background on GIS. I'll do my best to use the right wording and make myself clear what I am striving for. Also the only ...
2
votes
2answers
1k views

Openlayers - Get Type of Layer

Is there a way to get the type of all the layers in an OpenLayer maps object? What I am trying to do is iterate over all the layers in my OpenLayers map object and populate a dropdown list with the ...
2
votes
1answer
3k views

Adding layers using ArcGISDynamicMapServiceLayer

I am right now adding individual layers using FeatureLayer but it takes quite some time to load as the map is for US Counties (3076 count). I tried to load it using ArcGISDynamicMapServiceLayer but I ...
2
votes
1answer
582 views

Make Feature Layer tool problems in Model Builder

I am having a slight problem with using the Make Feature Layer tool in model builder. Basically I have a file geodatabase of points. I am trying to make a model to pull out points according to a ...
2
votes
1answer
1k views

Changing the name of layer using python

I am attempting to change the name of the layer. The following code changes the name of the layer but then removes the layer from the map, and I am not sure why. Note: I don't have any remove layer ...
2
votes
1answer
954 views

How to have a layer with many images that scale?

I know that in OpenLayers you can add Features to a Vector Layer which each have image but then they will not scale (i.e. their size stays the same independent of the current zoom) or at least I do ...
2
votes
3answers
2k views

Adding shapefile as layer in ArcMap via Python scripting?

I am trying to automate various tasks in ArcGIS Desktop (using ArcMap generally) with Python, and I keep needing a way to add a shapefile to the current map. (And then do stuff to it, but that's ...