1
vote
1answer
44 views

Why is interpolation adding too much heat

I am interpolating geo data using qgis. The data is in the form of lat,lon,count. The path of the collected data is shown as a mostly transparent line. The resulting heatmap it produces is shown. ...
0
votes
2answers
61 views

Identifying clusters of points within a given distance

So I have a database of lats/longs representing incidents occurring on or near roadways. My goal is to identify the street block areas with the highest number of incidents in the database. I don't ...
0
votes
1answer
28 views

Conditional formatting of grid cells based on specifict attribute

I'm using QGIS. I have a 29x30km grid. Every cell of the grid has its ID and every cell of the grid has an attribute "Population" ranged from 0 to 30000. What I would like to do, is to get some kind ...
1
vote
1answer
87 views

What exactly is the min/max of an extent? (QGIS heatmap plugin)

I'm having a hard time making the heatmap plugin do precisely what I want (namely, to make a heatmap showing not only points but an attribute of those points), and now I'm thinking that I may be ...
0
votes
1answer
57 views

Is it possible to use polygons to create heatmaps?

I hope I can explain my question clearly, so here it goes: I've been fiddling around with heatmaps on QGIS for a few days, but came across a small obstacle on my way. I have a dataset comprised of ...
0
votes
0answers
23 views

Crash upon heatmap

I am completely new to qgis. I am trying to generate some heatmaps from crime data... and failing miserably. I have tried with my own data and the data in the heatmap guide here ...
4
votes
1answer
96 views

How does QGIS calculate heatmap values?

I made a heatmap from points (with values) in QGIS, and now try to understand what the values in color scale are. Radius 300 map units (meters) Pixel size 10 map units (meters) Point values are ...
1
vote
1answer
65 views

Can one batch-automate the creation of QGIS heatmaps?

I have 4k point shapefiles, from which I would like to generate heatmap TIFFs using the QGIS heatmap plugin (or a functional equivalent featuring triweigth, radius and cell size selection). Is there ...
0
votes
0answers
44 views

Why does heatmap size vary with number of points

I am making three heatmaps based on points over the same area and don’t understand why the number of rows and columns would vary depending on the number of features. The first feature set has 398 ...
0
votes
1answer
40 views

Fail to get heatmap from MULTIPOINT column of Spatialite layer in QGIS?

I got a heatmap from a POINT column of spatialite layer. But, when I made another heatmap from MULTIPOINT column, it was blank. What is the possible reason of this problem?
1
vote
1answer
365 views

Weighted heatmap analysis- density of points, vs density of weight variable

Was just wondering if anyone could help me with a problem. I'm trying to map wellbeing scores (out of 10), using locations from a survey of 15,000 households, using the HEatmap command in QGIS. It's ...
2
votes
1answer
89 views

heat map of density ratio of 2 layers of points

I have 2 vector layers of points: one with a point for each house in the city (thanks to osm.org), roughly equivalent to population one with a point for each case of cholera in the city I'm trying ...
1
vote
0answers
97 views

Is there an analog to ArcGIS' “Neighborhood Toolset > Point Statistics” for QGIS?

Quick procedural question- is it possible to create a raster with QGIS in which the raster cell value is assigned by summing the number of vector points that are within a certain radial distance of ...
1
vote
2answers
667 views

QGIS - Continuous buffer image [Heat Map]

Is it possible to have the representation like the one the heat-map like the figure below using QGIS? The way seems to use buffer options, but I do not know how. Does exist any plugin that helps? I am ...
7
votes
1answer
326 views

Creating contours with meaningful values from point data

I recently obtained a CSV containing the locations of all recorded bicycle accidents in Boston over the past few years. As an avid cyclist, I'd like to create a simple contour map that draws attention ...
1
vote
0answers
34 views

Can I use the PyQgis QgisPluginLayer to create heatmaps?

I am working in an application to generate maps from a bunch of MIF/MID files, I already created almost all the maps that I need, but, now I want to create heatmaps. I can't find any way of creating ...
2
votes
1answer
78 views

Why do edits made in attribute table not show in associated layer? QGIS 1.8.0

I have compiled a heat map layer to display over a background raster map. I discovered that the heat map layer was incorrectly positioned because I had made an error in the coordinate entry fields of ...
0
votes
0answers
22 views

Trouble making heat map - red square [duplicate]

I'm a beginner to QGIS and I'm having trouble making my heat map. I'm using QGIS 1.8 and Win7. I imported a CSV file with around a 1000 points (X Y coords - WGS84). When I try to make a heat map ...
1
vote
2answers
86 views

How do I adjust transparency on heatmap so that I can see background raster map? QGIS 1.8.0

I have created a raster heatmap for the first time, but I cant seem to adjust the transparency settings to let me see another background OS raster map beneath it. I have attempted to swap the ...
1
vote
2answers
92 views

Why can't I save csv as a shapefile

I am trying to follow the instructions given here, Tutorial: Making Heatmaps using QGIS and GRASS , to build a heat map with my own data. I taken the first step and imported a csv data table into the ...
1
vote
0answers
99 views

Heatmap plugin with relatively small area

I'm trying to make a heatmap using points in a relatively small area (about 50km by 50km) and I just get a single red block every time (even after switching the color map to 'pseudocolor'). I've read ...
1
vote
1answer
207 views

Converting Heatmap into Grid of Points to regenerate less accurate Heatmap?

Question: How do you take a heatmap generated using a GIS software (arcgis, qgis...) and convert it into a uniform grid array of points which can be used to regenerate the heatmap (although with ...
4
votes
1answer
233 views

Getting Transparent Circles with Heatmap Plugin

With QGIS, I am trying to create a heatmap from a set of points I added as a layer using the "Add Delimited Text Layer" plugin. The points are a collection of complaints from around a city and I ...
8
votes
1answer
483 views

How to create a Human Trafficking Heatmap in QGIS?

I'm trying to create a heatmap with about 325 points distributed around the city of Houston. (FYI Houston is a major human trafficking in the US: a title shared with LA and Atlanta depending upon ...
0
votes
0answers
75 views

What vector file type yields the greatest detail with the Heat Map plugin?

I'm using .shp files built from .csv files and having quirky results. Perhaps there is a better way to begin. The heat map appears to be accurately describing the data but calculates a huge area in ...
2
votes
0answers
214 views

Can Nearest Neighbor Analysis help determine values for a Heat Map?

Given the below parameters (from Nearest Neighbor Analysis): A) Is there a definite range my Radius value should be within? B) Are there definite values my cell size should be near? C) Is there a ...
3
votes
1answer
65 views

What defines a Class in the Heat map plugin?

What defines a Class in the Heat map plugin? As in: "Black holes like that are usually caused by raster values exceeding the range of the color ramp. Try adding another class with a higher associated ...
6
votes
1answer
232 views

how to aggregate the rates, represented by points, within X radius

the point represents rates like 10%, etc. (this was also pretty clear from 2 years ago) -- been trying to do this for 2 yrs... the points dont represent numbers of events since they are rates ...
5
votes
1answer
239 views

How to create a heatmap using values?

How do I create a 'heatmap' in QGIS based on the values of the different points? I did do this once before with rainfall, but can't remember how!
2
votes
0answers
171 views

How can I map polygon value distribution?

I'm surveying an area and have a z-value attached to each polygon. In comparison to the area I'm studying the polygons are quite small. What I'm trying to do is show the distribution of this value. ...
2
votes
1answer
105 views

Error message 'Module qgis.v.kernel.rast.py not found'

How do I repair this error in QGIS: The error message was received whilst trying to run v.kernel from the modules list. I can however run v.kernel from the GRASS shell. A while ago, I installed ...
2
votes
1answer
480 views

Contour Lines Raster Extraction

I've been playing with Mapbox's blog post about converting heat maps to contour lines, and I'm stuck at the extraction part of this process. I used the CSV plugin to create a vector layer of points, ...
10
votes
6answers
1k views

How do I make a heat or Choropleth map that uses polygons in QGis?

I've been playing around with the heatmap plugin for QGIS and I am wondering if it is possible to make heatmap with using a similar plugin/tool that uses polygons as well as points? I would like to ...
6
votes
2answers
266 views

How do I compute v.kernel maps in less than 16 hours?

I am using the GRASS GIS 6.4.2 bundled with QGIS 1.8.0, using a PostGIS dataset exported via v.in.org.qgis from QGIS, to create kernel density maps. The layer has 738,288 points. My problem is the ...
4
votes
3answers
578 views

How to create an intensive map of Russia using QGIS or any other software?

I am trying to create an intensive (heat) map of Russia. I have an excel sheet of 36 Russian regions and their corresponding values. I know that there were similar questions: How to create a map ...
3
votes
1answer
554 views

Which parameter values should I use with QGIS Heatmap plugin?

I've read all the posts and docs about the heatmap plugin but can't seem to get it to work. The map is the size of the United States and has a little over 2000 points. I've tried small radi (1 ...
7
votes
1answer
198 views

Why is there a black hole in the Heatmap?

After running the Heatmap tool in QGIS I like to color the geoTiff according to my wishes. Using Psuedo color works fine, but it leaves me with no options, as type of color scheme or transparancy on ...
1
vote
0answers
325 views

Stats problem, QGIS heatmap [closed]

I am new to QGIS 1.8 and have been trying to make a heatmap. From what I can tell, the reason I am not getting the results I want is that the max value of the raster is erroneously measured at 2. ...
7
votes
1answer
510 views

How to adjust the granularity of a heat map in QGIS?

Not sure I am using the correct terminology here, so I have tried to describe my problem in detail. Please edit as needed. I have a layer of points, a layer of roads and a heat map in a raster layer. ...
3
votes
1answer
226 views

heatmap plugin slow/unresponsive in QGIS 1.8

I am trying to use the new heatmap plugin to create a heatmap from about 10k points. When I enter the parameters and start the process , QGIS becomes unresponsive. I don't get a progress bar or a ...
7
votes
2answers
2k views

How to use Heatmap plugin and its output?

I have a layer of points which I would like to depicted as a heatmap concentration of points for visualization. In QGIS 1.8 I tried the built-in heat map plugin, leaving the default values as is, and ...
4
votes
3answers
1k views

Where is the Heatmap Plugin

I have read the questions about creating heatmaps but I cannot find the Heatmap Plugin in any of the repositories or using the fetch python plugins, it simply is not there. Could someone please tell ...
2
votes
3answers
1k views

How to generate heatmaps with QGIS1.9 plugin automatically?

I created a few heatmaps with the new plugin in QGIS 1.9, but now I would like to generate a lot of them automatically. How should I do? I created a few of them by hand, but I should first import the ...
4
votes
2answers
2k views

How to create heatmap (concentration of points) in QGIS?

There was already a question about it in 2010, where the answer was basically "use QGIS Heatmap plugin". I've also read on QGIS webpage that it is now "implemented as a native C++ plugin" My ...
51
votes
4answers
18k views

How to build effective heat-maps?

Using ArcGIS, QuantumGIS, Grass, and/or GVSIG What are some of the tools and processes involved in building effective heat maps? What are the plugins involved? What are the major data requirements? ...