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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7
votes
3answers
781 views

Filtering out canopies and buildings from DSM to have a bare earth elevation

Can anyone suggest methods in filtering out trees and buildings from a DSM so as to come up with a reliable DEM? What I have is a grid from a LIDAR data (.tif file, with 1m resolution). I was going ...
2
votes
1answer
198 views

QGIS Filters and Queries

In QGIS is there a way to filter a layer using the Query Builder to show all values which include a particular phrase. For example I have a list of organisations and I want to filter all those which ...
2
votes
2answers
2k 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 - http://www.youtube.com/watch?v=XUD6zcNGl4A&list=UUZkLX9x-...
0
votes
2answers
457 views

Filter OSM files with Osmosis

I have to filter the whole Malta dataset with Osmosis only considering cycleways, footways (including used nodes of those ways) and all nodes with the tag value tourism and amenity. I write the ...
1
vote
1answer
98 views

QGIS: Turning Filter On and Off

When a filter is applied to a layer the layer cannot be edited. Is there any way of quickly turning the filter on or off without entering the Query Builder dialog box and removing the filter?
1
vote
0answers
53 views

C++ parser for OGC Filter Encoding 1.0

I'm developing a C++ application and I have to parse a OGC Filter in order to implement querying functionality on a metadata repository. Does anyone know any C++ library to parse OGC Filters? Thanks.
1
vote
1answer
230 views

How to filter data by category, then map only maximum-value row for each?

I'm building a consolidated map of all transit systems in my area in QGIS. I have a GTFS dataset of bus lines, and it includes shapes for every trip on every route in the system (as it should), but ...
1
vote
0answers
299 views

SetSpatialFilter worked unexpected when using ogr by python

I am using ogr python binding to read the shapfile, this is the code: ..... bbox="POLYGON ((20.18164062 30.63867188,20.63867188 30.63867188,20.63867188 30.18164062,20.18164062 30.18164062,20.18164062 ...
2
votes
1answer
433 views

PostGIS views vs WFS Filtering operations on PostGIS table

In what use cases should I prefer writing PostGIS views for filtering datasets versus filtering with WFS filter encoding operators and vice versa? In both cases I would be serving the data via ...
0
votes
1answer
233 views

WFS Filter Buffer around a point

I'm trying to make a buffer around a geometry (point/s,linestring,etc) using WFS queries without luck. This is what I've been doing: <ogc:Filter> ... <ogc:Function name="...
2
votes
1answer
2k views

WFS 2.0 with bbox filter and attribute filter

I am trying to get the following WFS GET request to work: wfs = "service=WFS&version=2.0.0&request=GetFeature", name = "&typeName=storeName:layerName", bboxFilter = '&bbox=' + bounds....
1
vote
2answers
470 views

Avoid NoData after Focal Statistics Majority

I am currently working with some classified land cover rasters (containing 8 land cover classes) in ArcGIS 10.0. I would like to make them look smoother and have therefore used the Focal Statistics ...
-1
votes
2answers
165 views

Using floating point raster image for majority filter in ArcGIS?

I'm trying to do filter images using Majority filter in ArcGIS. My input images is a float point raster image in .img format. There is an error saying "Invalid parameters". What does it mean?
0
votes
1answer
439 views

Filter geojson or shapefiles

I'm trying to create a geojson file with a few shapes of roads from OSM. Now, I've been able to get shapefiles of the greater region (province) these roads are in from http://download.geofabrik.de/ . ...
1
vote
1answer
488 views

QGIS 2.2 - expression string builder to ignore NULL values

Simply put, I would like to create a rule-based filter whereby you add 2 columns together and you get a certain colour as a result. However, some fields in Column_1 may be NULL and those exact same ...
0
votes
1answer
345 views

how to filter point features based on the filterted polygons with OpenLayers

I have one WFS polygon layer and one WFS point layer. The polygon layer has an attribute user_id. The web map has two requirements. Filter the polygons based on the attribute user_id. That is, a ...
0
votes
1answer
116 views

filtering GeoRSSLayer contents in arcgis javascript API?

I would like to make use of a public geoRSS feed with content from 10years (200+ items), however since it is too much information, i would like to show only a subset of this content in my map... I ...
1
vote
2answers
882 views

Using sieve filter in ERDAS Imagine and/or ArcGIS for Desktop?

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.
0
votes
0answers
31 views

How can I remove dipoles from rasterlayer in QGIS 2.2?

I work with geomagnetic survey data. When convertet into a rasterlayer, every object with a high magnetic potential (for exampel an iron-nail on the surface) is shown as very sharp anomalie called ...
2
votes
2answers
3k 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 ...
1
vote
1answer
924 views

How to use paging in a WFS query?

I am running a GetFeature request against a WFS server which does not support to download all data at once. Can I use ogc:PropertyIsGreaterThanOrEqualTo to split the dataset into chunks at download ...
1
vote
1answer
231 views

Filter on a array of value in OpenLayers

I'm running into an issue. I have an array of value coming from a JSON POST. After retrieving these values and storing them into a var, I need to filter an OpenLayers layer with this values. I'm ...
2
votes
2answers
2k views

QGIS Advanced String Filter Expression returns too many results

"GNR" is a string column and I expect the filter expression "GNR"='.11' to only return the feature with the value '0.11'. Why are the other features with values of '.110'and '.1100' included? Is ...
1
vote
1answer
102 views

How to query data like only for point by from a grouplayer by using WMSGetFeatureInfo in Openlayers?

till now I have been known how to query data from a groupLayer by using WMSGetFeatureInfo while the point is it shows a lot of associate results features,so I aim to query a single layer infomation ...
0
votes
2answers
430 views

What is the bounding box of filtered features?

I'm using geoserver to store a number of gps tracks that are recorded during test drives with a number of vehicles. I have a layer defined that contains the following columns in the database: date ...
1
vote
1answer
444 views

MapServer: Default spatial filter

I have MapServer setup to display data (both WMS and WFS), however I'm having a problem adding a default filter. There's is an area on the map that users should not be able to retrieve features from. ...
0
votes
1answer
311 views

[mapserver]: layer filtering with layerObj.setFilter()

I'm trying to filter a layer (using mapserver) backed by a Shapefile using layerObj.setFilter() but this doesn't seem to have any effect on the returned tile(s). Sample code: layerObj = mapserver....
2
votes
0answers
538 views

How to use SLD to filter a WMS layer but without setting any styles?

I'm trying to filter (using OpenLayers) a WMS layer, served by MapServer. I've got this working by building the appropriate OpenLayers.Filter rule(s) with an empty Polygon symbolizer (so no specific ...
6
votes
2answers
835 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 ...
1
vote
2answers
293 views

Filter out osm data that have been edited after some timestamp

I want to get data after some timestamp. I have downloaded the osm file of the area. I went through the osmosis documentation but could not find a way to filter it by time. The result should be same ...
0
votes
1answer
604 views

Geoserver: WFS/WMS query by month on Date datatype

I have a GeoServer running, using a Postgis database as storage for a workspace with a few different layers. These layers are accessible through WMS or WFS. One of the variables in this database is ...
0
votes
1answer
2k views

Use new OpenLayers.Filter.Logical from OpenLayers into jQuery

I've a small GIS app, displaying stations on a map. Very simple. At start, none of the stations are displayed, even if its layer is enabled. What I want, when I click on a div, is to display one the ...
2
votes
2answers
371 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 ...
0
votes
1answer
152 views

WFS Filtered : The filters that worked for me in 1.8 - gives no results in 2.0

Using Quantum GIS 1.8.0 and 2.0.1 desktop on windows XP 32bit Server: http://vmgeoserver.vd.dk/geoserver/VD/ows?version=1.1.0 Setting filter for VD:vma_admdata: "BESTYRER" = '230' AND "...
3
votes
0answers
147 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 ...
0
votes
1answer
2k views

Geodjango: Using Lat / Lon to Buffer from Point

I want to have a radius based distance search. To do this, I want to create a buffer around a point object so that I can filter objects that are inside this buffer, a method that I learned based on a ...
0
votes
0answers
304 views

OpenLayers Mapserver spatial filter INTERSECTS format problems

Trying to get hand-drawn polygon delimiter for spatial query via OpenLayers to mapserver (then postgis). I can get the WKT of the drawn polygon and can substitute the dynamic values, but am having ...
1
vote
2answers
760 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 attributes....
1
vote
2answers
588 views

How to extract features with specific coordinates from a ShapeFile?

I would like to extract a number of features from a ShapeFile which match with specific latitude/longitude values. I am interested if/how this can be done with QGIS and ogr2ogr. The output should be ...
0
votes
1answer
101 views

Mapserver 6.2 concatenate attributes in FILTER

Back in version 5.0 I had: FILTER ("<tcode:expression/>" eq '[STATE][COUNTY]') final version = FILTER ("11000" eq '[STATE][COUNTY]') so I would filter out the features with state = 11 and ...
0
votes
1answer
565 views

How add vector style rule filter with different value in table

I have a simple wfs layer from geoserver, here is code: //wfs-t editable overlay var wfs_layer = new OpenLayers.Layer.Vector("Vector sample", { strategies: [new OpenLayers.Strategy.Fixed()], /...
1
vote
0answers
149 views

Kalmanfilter GNSS IMU

I want to make an uncoupled Kalman filter. The input data are GPS and the output of my strapdown Algorithm from the IMU. The Strapdown Algorithm is used to calculate the actual position and velocity ...
0
votes
1answer
134 views

Intersects Filter on WFS 1.0.0

I use WFS=1.0.0 on the Mapserver v5.6.6 and v6.0.1 with MS4W package. I want to get the Intersects of Spatial Operator. When I make getcapabilities request I see just "Intersect" like: ogc:...
3
votes
1answer
456 views

How to set a spatial filter with Python/GDAL?

Is there a way with GDAL (Python) to set a spatial filter (bounding-box) on a raster before I process it? I want to read it as an array. BandReadAsArray(band, xoff=0, yoff=0, win_xsize=None, ...
1
vote
0answers
132 views

How do I account for changing latitude with a spatial filter?

I'm working with data in latitude/longitude grid form in a non-GIS specialised package (MATLAB) and wish to apply spatial filters to it. As this data contains a broad range of latitudes and is ...
10
votes
1answer
817 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 ...
0
votes
1answer
510 views

Local variance image in python using gdal and a running window approach

I want a local variance image with a 3x3 of a geospatial raster image using python. My approach so far was to read in the raster band as an array, then using matrix notation to run a moving window and ...
1
vote
1answer
126 views

GeoServer FeatureID Filter Limits

we've made an application that uses GeoServer WMS tiles on an OpenLayers map. We have a layer of Bus Stops which we filter based on search results from previous search i.e. User searches for 'The ...
2
votes
1answer
529 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: http://localhost:8080/geoserver/...
1
vote
2answers
1k views

GeoServer Where clause filter

I use postgis, geoserver and openlayers for gis development. I simply reach from goeserver to postgis table or view and show it with openlayers. but I need some filtering operation on my spatial ...