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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25
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5answers
18k views

What is difference between map layer and spatial dataset (e.g. feature class, shapefile)?

What is the difference between feature class and feature layer? To me they seems very similar in concept.
11
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8answers
10k views

How to georeference a vector layer with control points?

I have a non-georeferenced vector layer that I need to be georeferenced. With raster layers the task is easy and straightforward, but I have no idea what should I do with my vector layer. I have a few ...
9
votes
1answer
6k views

Use python to add layers to TOC

I've been battling with adding layers to the TOC for some time now. I have managed to single layers added but need to loop through a folder and add all layers. Shapefiles I cannot get to add at all. ...
11
votes
2answers
11k views

Changing data source path involving feature dataset in *.lyr files using ArcPy?

How can one change the source data paths for every layer file in folder X using arcpy? I've followed Updating and fixing data sources with arcpy.mapping as best I can, yet all I get is an unhelpful ...
10
votes
1answer
2k views

Sort layers in QGIS table of contents?

When I load a bunch of layers into QGIS from PostGIS, they seem to load in reverse alphabetical order. Is there any tools or plugins that allow you to quickly sort the QGIS TOC in a different order? ...
16
votes
6answers
6k views

How to improve rendering performance of very large shapefile?

I have a polygon shapefile that has a 100MB .dbf and 500MB .shp file component. The reason it is so large is it is a landbase classification for a whole district. Everytime I am viewing the file in ...
7
votes
2answers
7k views

Using Google Maps as layer in ArcMap?

Can I use Google Maps as a layer in ArcMap? Is it possible?
2
votes
2answers
231 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
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 ?
7
votes
1answer
2k views

How to perform a true GIS clip of polygons layer using a polygon layer in R?

I would like to do a true GIS Clip in R of soils polygons using a series of single boundary polygons, but I cannot find an R function to properly do it. It should work just like the CLIP function in ...
5
votes
1answer
1k views

what dictates the drawing order of overlapping features with in the same layer/feature class in ArcGIS?

I know that in ArcGIS drawing order is controlled by layers, and if I want to make some features be drawn on top of other features I can use definition queries to separate them into different layers ...
8
votes
1answer
3k views

Can I change properties of several layers simultaneously?

I'm working on bulk data. I have a few hundred GeoTIFF images imported into a QGIS project, and I'd like to modify their layer properties - things like the no-data-value, transparency of certain pixel ...
3
votes
1answer
3k views

XYZ Layer in Open Layers has Missing Tiles

In Open Layers I'm having a missing tile problem where it generates a missing link icon and a pink background. I found several threads including this one saying to add this code ...
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
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 ...
5
votes
1answer
2k views

Export each layer in map to a separate image

I have a mxd file with multiple layers I have to export to PNG/JPG. I would like to create a script which turns on layers one at the time before they are exported. So far I have come up with the ...
2
votes
1answer
324 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
288 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 ...
1
vote
0answers
232 views

Download layers from arcGIS online in python [closed]

How can I get layers/maps from arcgis online in Python? I mean to download layers from Arcgis online in python, just like publishing. I've searched about it in the documentation of Arcgis 10.2.2, but ...
3
votes
5answers
3k views

Adding Raster Layer without lyr file using ArcPy?

i wonder how i can add a raster layer to a remote (not the current) mxd file with arcpy. I need to not use a lyr file for that. For vector Layer i have the following lines working fine : mxdPath = ...
2
votes
2answers
137 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
3answers
11k views

Merging Two or More Layers using ArcGIS for Desktop?

I am working with three clipped layers that are shown in the TOC. I created these layers from a large watershed shape-file. However, each clipped layer includes the layer before it and only expands on ...
1
vote
1answer
820 views

OpenLayers & Google Maps: TERRAIN not showing as baseMap

I have a problem with OpenLayers and Google maps: on this page: http://46.37.22.75:8085/public/ I'm loading Google maps TERRAIN with Openlayers.js, everything worked well for about 1 year, but now ...
1
vote
1answer
132 views

Using layer file to apply symbology to shapefile with ArcPy?

I have code that doesn't work at the moment: # Import arcpy module import arcpy # Script arguments Input = arcpy.GetParameterAsText(0) if Input == '#' or not Input: Input = "frame" # provide a ...
1
vote
2answers
1k views

How to avoid “Handle bad layers” message when using QGIS Flowmapper plugin?

In QGIS, if I close a project and try to open it a few days later I often get a message that says "Handle bad layers". This is very frustrating because when I open the project various layers will have ...
-1
votes
3answers
335 views

Insert layer file to specific data frame

I have a folder that contain mxd's projects. Each mxd has 3 and more data frame. I want to insert layer file to a specific data frame with position in the TOC. I don't know how to do it. I'm trying ...
5
votes
2answers
3k views

What is Python equivalent of ModelBuilder's Iterate Feature Selection?

My data consists of two featureclasses: Points = points representing trees Polygons = Polygons representing % canopy area by area. Each polygon in the FC has a % canopy measurement in the ...
3
votes
2answers
3k 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 ...
1
vote
2answers
5k views

How to get names of all layers in a store in GeoServer using OpenLayers

I have strict requirement to retrieve names of all layers in a GeoServer store using OpenLayers. I've gone through the post here, but it doesn't answer my question. I've also gone through GeoServer's ...
4
votes
1answer
6k views

How to set up a layer control using Leaflet?

I have been working on a mapping application using Leaflet. I am using a WMS on Geoserver to get my layers, which are overlaid on a cloudmade basemap. I tried to use the layer control on my map by ...
1
vote
1answer
814 views

How to query all layers in ArcMap and get access to them by name or index?

I have ArcMap with tons of layers. Some of these layers may contain another layers with data (aka Composite layers) or they don't. The depth of composite layers in unknown. I need to query all layer ...
1
vote
2answers
216 views

Open mail client when clicking feature in Attribute Table

One of the attributes/features of my layer contains an email address. I'd like to be able to open the default mail client by clicking on the mail address from the Attribute Table. After some initial ...
8
votes
3answers
5k views

Z-index in OpenLayers 3: layer ordering in OL3

Is there a method to change Z-indexes of layers in OpenLayers3 like it was in old version? map.setLayerIndex(markers, 99); //set the marker layer to an arbitrarily high layer index I need to change ...
7
votes
3answers
4k views

Layer loadstart & loadend events in OpenLayers 3

OpenLayers 2 has these layer events "loadstart & loadend." What is equivalent to them in OpenLayers 3? While a vector layer loads and is rendered, I need to show a loading icon.
6
votes
1answer
3k views

Delete layer from ArcMap using Python

Problem: I'm trying to loop through all my layers looking for layer named "CADAnnotation". If the layer exists then remove the layer from the mxd Notes: Running from Stand-Alone script (ie. NOT ...
6
votes
2answers
2k views

Can QGIS preserve layers when exporting a PDF? [duplicate]

I saw this posted about a year ago (Can QGIS preserve layers when exporting to PDF?) but figured it was worth asking again -- is this possible? My usual workflow with ArcGIS is to export to AI then ...
3
votes
1answer
313 views

Show alternating contour lines

Is it possible to show only every other counture line? And how do you do that? (Im new to QGIS Lisboa 1.8.0, but even newer to QGIS Dufour 2.0.1, but have used ArcGIS a bit a while ago, and also ...
3
votes
2answers
2k 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?
2
votes
2answers
831 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
765 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
1answer
133 views

Keeping a vector layer always on top

I want to know how to keep a layer always on top of other layers! After adding a vector layer ( QgisInterface->addVectorLayer ), I want that layer to always be displayed on top of layers added later. ...
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 ...
4
votes
2answers
1k views

How to get layer type in OpenLayers 3?

I would like to iterate through all of the added layers in an ol.Map instance and only select the vector layers. So far I could get the individual layers with the a property of the resulting object of ...
4
votes
1answer
3k views

Layer visibility using maxscale minscale not working

I'm using Openlayer and Geoserver. I have a series of layers that have a scale parameter like: 1:50000-1:25000 where 50000 is the max scale while 25000 is the minscale. I have a map like in this ...
3
votes
1answer
376 views

How to replace the legacy function “doQueries ” to AMD ESRI Javascript format?

I'm trying to understand the migration of ESRI API for javascript, from legacy to AMD. In the case of this example, how replace the fucntion doqueries????: function init() { map = new ...
2
votes
0answers
79 views

How to make a model with more than 2 input layers for buffering and merging?

Would it be possible to add more inputs to Buffer and Merge? From what I can see there is a limit of two input layers per both. As far as I know this is possible in ArcGIS's Model Builder but from the ...
2
votes
2answers
535 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
260 views

Ordering Cartodb torque visualization over Google Maps heatmap layer

I am attempting to create a map with two layers: a CartoDB Torque visualization on top and a Google heatmap layer underneath. So far I have only been able to get them to draw in the opposite order ...
2
votes
2answers
4k 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
380 views

Listing Elements or Datasets of Layer gives ERROR 000840 value is not Feature Layer?

I used Ar5cPy to do batch processing of Network Analyst - Make Service Area layer of thousand of stores. Everything went well except now, I am stuck with layer (.lyr) files and I would like to ...