To show, hide, extract, or remove particular data from a larger set, narrowing it down, or the specific criteria used to do so.

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11
votes
2answers
3k views

How to filter big datasets in Geoserver WMS?

Is there a good way to filter datasets with approx 50,000 features in Geoserver? I'd have to select between 100 and 200 features based on ids. These ids are different from the FeatureIds. Couldn't ...
8
votes
1answer
833 views

How to apply a Majority filter in GRASS GIS?

I was wondering if someone could help me write a majority filter for GRASS GIS. I have this map (see below) which I need to run a filter over to make the red areas a bit more dominant. I know I can ...
7
votes
2answers
407 views

Using ArcGIS to filter cells where 7 or 8 of the neighbors are different

I have land cover data that I would like to clean using some generalization tools. Majority filter does almost exactly what I want, but is missing one key option. Majority filter allows you to change ...
6
votes
1answer
627 views

PostGIS query vs QGIS filter

I have a PostGIS dataset with around 3 million shapes. I only need to view about 1,500 of these shapes at any given time, but the shapes I need to see depends on which feature is selected in a ...
6
votes
1answer
1k views

How to filter wrong GPS readings?

I have absolutely no experience with GIS, it just so happens that one of the hobby projects I am doing at the local hackerspace includes tracking a model boat with a GPS... I hope this is the right ...
5
votes
2answers
367 views

How to de-noise a DSM

I have created a DEM, DSM, and nDSM from a LiDAR Point Cloud using SAGA-GIS. I extracted the appropriate returns from the point cloud, then converted to grid, and then closed gaps to fill in any ...
5
votes
1answer
428 views

Create custom Authentication filter in GeoServer 2.3.0

Context In my current project, I've the requirement to validate that requests coming to GeoServer (2.3.0) are allowed. The project holds those facts: the GS client cannot provide the principal ...
4
votes
2answers
1k views

What is the best approach to using IQueryFilter.WhereClause in ArcObjects?

What is your preferred / best approach to using IQueryFilter.WhereClause statements in ArcObjects (e.g. when selecting features by attributes)? You need to check the source type (shapefile / personal ...
4
votes
2answers
74 views

Filtering Overpass-API by country

Does anyone know how to perform a overpass-api request like this? "Show me all banks in Germany"? I could just show all 'amenity = bank' in a specific bounding-box. But Germany (or most of all ...
4
votes
1answer
132 views

Getting feature at point in C#

I want to get the feature at where mouse was clicked in map. So I was wondering how to get features which intersects with that point. Plus I was wondering how can I check what type of object it is ...
4
votes
3answers
3k views

How to properly utilize DWITHIN Spatial Filter in OpenLayers

Given the following code: var points = []; points.push(new OpenLayers.Geometry.Point(-110, 38)); points.push(new OpenLayers.Geometry.Point(-108, 40)); var lineString = ...
4
votes
2answers
846 views

OpenLayers.Filter.Comparison.LIKE doesn't filter special characters!

it seems like OpenLayers.Filter.Comparison.LIKE doesn't filter special characters! for example, filter = new OpenLayers.Filter.Comparison({ type: OpenLayers.Filter.Comparison.LIKE, ...
4
votes
1answer
237 views

Given a known batch of mobile-obtained gps data with timestamps, what algorithms can be used to clean it?

I'm working on the backend for an iOS/Android app that collects locations every hour and syncs with the server every three hours. The mobile apps themselves are not under my control and so I can't ...
3
votes
2answers
3k views

OpenLayers: Combine multiple OGC filters

I have two OGC filters client side: <ogc:Filter xmlns:ogc="http://www.opengis.net/ogc"> <ogc:PropertyIsEqualTo matchCase="true"> ...
3
votes
1answer
3k views

How to filter features in a layer?

I am trying to display certain features in a shapefile-based layer using QGIS. I have found the subset function in the properties panel, which does exactly what i want, but is too tedious given that I ...
3
votes
1answer
263 views

How to filter layer of osm data?

I have a table osm_roads that has a column named geometry geometry geometry(LineString,900913). If I want to filter a city to draw districts, I cannot do it by geographic coordinates? What if in ...
3
votes
1answer
926 views

Openlayers: OGC Filter problem

I have a problem with OGC filter. My layer in OpenLayers has this filter: filter: new OpenLayers.Filter.Comparison({ type: OpenLayers.Filter.Comparison.BETWEEN, property: ...
3
votes
2answers
1k views

OpenLayers spatial filter polygon problem

I've got a dataset of English Counties (currently cut down for testing) that I'm serving from SQL 2008 using MapServer and OpenLayers. The features in my dataset are appearing in the right location on ...
3
votes
1answer
863 views

Case Insensitive WFS Attribute Search with ArcGIS Server?

I'm using ArcGIS 9.3.1 to host WMS and WFS services. I have a map (.mxd file) with a layer whose attribute table includes fields with mixed-case string data. When I open this map in ArcMap and ...
3
votes
0answers
99 views

Filtered SimpleFeatureCollection really slow on Map and other operations

I'm working with a shapefile having about 85.000 features. I need to select some of these using a filter and then showing these on a map. Now... If I draw the entire shapefile's features the creation ...
3
votes
0answers
404 views

SLD filter with embedded strTrim function in Geoserver

Using Geoserver 2.2.2 (GeoTools Version 8.4) on Windows 7, I'm trying to create a SLD that trims the leading and trailing spaces of a string property (using the strTrim function) and compares it to a ...
2
votes
2answers
373 views

How can I tell mapserver to ignore a filter that is set in a mapfile?

How can I tell mapserver to ignore a filter that is set in a mapfile? I am displaying a wms layer with point features using mapserver. In one of the layers in my mapfile I have defined a filter ...
2
votes
1answer
121 views

spatial data filtering without GIS?

I have access to a database here (description of the columns are also available) containing spatial data in text format and with WGS84-EPSG:4326 coordinates. I would like to only select data in my ...
2
votes
1answer
852 views

Filtering a raster by pixel value ? (Qgis)

I have downloaded Globcover data in GeoTIFF format. I want to create a new grid which only has values where the Globcover data (the only band in the TIF file) has one certain value (==190). Can I do ...
2
votes
3answers
4k views

OpenLayers WFS protocol: work with filters if the protocol is defined out of layer constructor

follow question:wfs-load-feature-check the scenario is: i am trying to load a WFS layer, since it takes a while to load all features, I want to give user a notice while waiting for response. the ...
2
votes
2answers
2k views

What class/types of smartphone chipsets support GPS, A-GPS, GLONASS AND have extended kalman filtering?

I've been testing several Android phones (all running Android 4+) Sony Xperia T, Moto G, Nexus and HTC 1 which are all giving decent tracks (all of which use GPS/GLONASS) However we are also using ...
2
votes
2answers
232 views

OpenLayers.Format.SLD - Ignores 'matchCase'?

I've trying to use OpenLayers to construct an SLD element to include in a WMS layer's parameters. This SLD document can contain a number of filters. This works fine and resultant SLD does work to ...
2
votes
2answers
198 views

Query/find features in ArcPad, hide the rest in map?

Trying to help out another department that does quarterly assessments of field data. Their symbology is all set by the status of the assessment (the only way I could figure out how to hide something ...
2
votes
1answer
28 views

How to apply a filter to multiple vector layers in QGIS?

I am trying to apply an attribute filter to multiple layers in QGIS at once. The filter is to be applied to .osm data brought in through PostGIS to QGIS. I have tried selecting multiple layers -> ...
2
votes
2answers
439 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
1answer
251 views

How to filter or query data in GRASS?

I have a PostGIS dataset with just over 2 million rows. Each row has a PostGIS geometry point value and several attributes. I'd like to do some analysis on certain subsets of the data, but I can't ...
2
votes
1answer
416 views

Filter Points Layer by Polygon Layer

I come from the Java world and go straight to C# and ArcGis 10 (I have to make a simple task for the university). So this means I don't really know much of C# but I can live with it and don't know ...
2
votes
1answer
93 views

Filter query error in QGIS2.4 or 2.6

I get this error when undertaking in query in QGIS2.4 or QGIS2.6: An error occurred when executing the query. The data provider said: OGR[3] error 1: Unrecognised field name ...
2
votes
1answer
64 views

How to filter out osm data made by specific users - osmosis or a better suggestion

I am trying to find the code for a query in osmosis that will allow me to download only contributions made by certain OpenStreetMap users. I was thinking to use osmosis to filter out all the ...
2
votes
1answer
68 views

Filtering MSSQL layers in QGIS doesnt work

In my QGIS Plugin I am filtering layers with this Python code: FeatureIterator = layer.getFeatures( QgsFeatureRequest().setFilterExpression ("Fieldname='SomeValue'") ) for feature in FeatureIterator ...
2
votes
1answer
99 views

Is it possible to use a WHERE clause with Grass v.in.ogr for DGN sources?

I am trying to import a .DGN with Grass v.in.ogr in QGIS. I am able to import the DGN perfectly, but I would like to filter the elements using the WHERE option. From searching, reading and testing I ...
2
votes
1answer
816 views

Filtering a loaded kml file in OpenLayers

I'm trying to create an interactive search engine (for finding event tickets) of which one of its features is a visual map that shows related venues using OpenLayers. I have a plethora of venues ...
2
votes
2answers
1k views

GeoMedia WebMap with WFS 1.1.0 Filter Examples?

I'm having problems forming a GET query for WebMap spatial data using WFS 1.1.0. My query looks like this: ...
2
votes
1answer
728 views

How to query some properties of a list of typenames in geoserver

I want to query selected propertynames from a list of Typenames in Geoserver. I could find an example from OGC WMS 1.1.0 Implementation Specification ( pdf document page 80 Example 10) which is not ...
2
votes
1answer
581 views

Is there any way to perform spatial filter on multiple layers together?

I have a scenario where a featureclass[Child Version] is queried for some overlapping features on [SDE.DEFAULT] Version using ISpatialFilter, After getting few result, these features are looped and ...
2
votes
0answers
24 views

How to remove spikes from grid in SAGA GIS?

I tried to get a grid by interpolating LAS file using Ordinary Kriging. But the product grid has many pixels which values strongly stands out from average surface - I mean one pixel sinks nad spikes. ...
2
votes
0answers
22 views

How to select points as geomtry in QGIS when both multipolygons and points are stated within the wfs-server?

I'm trying to show data from the following server in QGIS: h ttp://geodata.nationaalgeoregister.nl/bag/wfs? I made a filter on the data I would like to appear in my map. This is how I stated the ...
2
votes
0answers
59 views

SLD question regarding filter

I had a problem with my SLD today, I actually solved my issue but i'm very curious if there's another way around it, Mainly because my method is a hassle and may not work in other situations. I've ...
2
votes
0answers
44 views

How to Use GetGeomtype Gdal Python

I am just wondering what I am doing wrong when trying to use the GetGeomType. I need to focus on separating layers from a pix file. Two categories are the bitmaps(which are vectors) and then the ...
2
votes
0answers
307 views

Geoserver CQL Cross Layer Intersection Failing

I am having trouble forming a properly formatted CQL request using geoServer cross layer filer functions and was hoping others could assist. My request is as follows: ...
2
votes
1answer
424 views

combine two OCG filters in Openlayers : ERROR: invalid input syntax for integer

i need to combine two OCG filters. each one works fine separably but if i combine them using Filter.Logical.OR, the first one works only. var c_filter = new OpenLayers.Filter.Logical({ type: ...
1
vote
2answers
41 views

Display only the features containing a name

I used QGis to open a shapefile with the rivers in my state (Rio Grande do Sul, Brazil). I would like to know "the name of every river", but when I click on the rivers, most of the small ones don't ...
1
vote
3answers
2k views

How to show vector features in OpenLayers after hiding it?

I did change some vector features style (through check-boxes) using style property : var features = layer.features; for( var i = 0; i < features.length; i++ ) { //features[i].style = { ...
1
vote
2answers
232 views

Where can i use a sieve filter?

Where can i use a sieve filter for my supervised classification? Can i do it in Erdas Imagine or in ArcGIS? I can't find it anywhere. Thank you
1
vote
2answers
451 views

Custom filters (server side) for Openlayers Vector Layer

I have a vector layer in openlayers with source in GEOJSON (custom php server, which I have in complete control) and BBOX strategy. Vector points contain point sources which have different ...