Collecting and analyzing numerical data or making numerical summaries of data.

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0
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0answers
38 views

How to extract high frequencies from a point shapefile?

I need to get the average of the 3 highest frequencies in a table and append it to a shape file i already have hope you can help me
3
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1answer
248 views

Setting Band Statistics on Raster Image (GeoTIFF)

After doing calculations on a raster and saving it, the image statistics are wrong and need updating. I find examples saying that this should do the job, like in this example: ...
4
votes
2answers
1k views

GDAL does not ignore NoData value

I am trying to calcualate the statistics of a TIFF. The script should ignore the NoData value, but doesn't. What causes this? import gdal from gdalconst import * # register all of the drivers ...
3
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1answer
56 views

World territorial units for statistics

My current assignment required to do research and produce world territorial units for statistics. In Europe it easy thanks to Eurostat. Even non-commercial GIS data is also available here. Now ...
2
votes
1answer
111 views

Create ERDAS IMG Statistics using GDAL C++ API?

I want to create very many ERDAS .img files using GDAL under C++. I don't want to have to process them all in ArcMap to create statistics for them (mainly because ArcMap fumbles when calculating ...
2
votes
1answer
254 views

Error 010240 with ZonalStatistics

I have a code that calculates the sum of water recharge for a pixel for a 9 year period (This piece of code works fine, just thought I would show how it is made just in case. The values range from 0 ...
2
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1answer
345 views

Accounting for Spatial Autocorrelation in ZINB Model?

I'm doing an analysis on disease in Chile. I'm using the rate as the Dependent Variable and both remote sensing and housing-type data as the Independent Variables. I have several questions regarding ...
7
votes
3answers
514 views

How to use ZonalStats plugin?

I am using QGIS 1.8.0 on a Windows Home Premium 7 machine. I have a single band TIFF that is 187 MB in size. My vector polygon shapefile represents a regular grid of a 147x112 36kmx36km grid cells. ...
2
votes
1answer
202 views

STATISTICS not allowed in the Attribute Table

I created a shapefile, calculated geometry then went to grab the stats, the statistics was ghosted, not allowing me to grab those numbers. I am using 10.1 ArcView. I deleted the field and created a ...
3
votes
1answer
662 views

API for Real Time World Statistics

Does anyone know of an API (preferably free) that can provide real time world statistics such as Crude Birth Rate, Crude Death Rate, world/country population, or emails sent today as on the website ...
3
votes
2answers
852 views

How to find out the Basin Length?

I am doing Project on Drainage basin, to find out the Elongation ratio I need to find out Basin length, Can any one of you tell me how to find out BASIN LENGTH using ArcGIS or any other way. My data ...
7
votes
1answer
2k views

Are there QGIS tools that will allow users to get tabular statistics from their table?

Are there QGIS tools that will allow users to get tabular statistics from their table? I kind of expected I would be able to just open the table, select the field I was interested in, right-click on ...
3
votes
2answers
591 views

How to create a standard deviation map from three rasters in QGIS?

I have 3 normalised (0-100) raster maps. Is it possible to get a map which shows the standard deviation? I'd like to see the areas with smaller and higher std deviation. Thank you!
5
votes
2answers
3k views

Calculate area of intersecting polygons in QGIS

I have two collections of shapefiles: 1 - postal codes, administrative and political areas 2 - various land use categories like parks & allotments, and points like trees I want to produce ...
4
votes
1answer
2k views

How to detect duplicate attribute values in a table using ArcPy

In ArcMap, the right-click Summarize option very quickly creates a frequency listing of the chosen field: Note that the count field shows the count of duplicate values. How can I access this ...
2
votes
0answers
308 views

On using R data with ArcPy to make histogram in ArcMap

I am writing a tool in python which passes parameters to a R script, which in turn creates a DBF file. I read this DBF and want to make a histogram out of the data inside ArcMap as one of the results ...
1
vote
0answers
349 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. ...
2
votes
0answers
330 views

How do I create a leader line for a label in my bar graph in ArcMap?

I am displaying a bar graph of various tornado watches and warnings along with the actual tornado touchdowns themselves. Since the tornado touchdowns are such a small number compared to the large ...
2
votes
1answer
49 views

What is the method for finding the percentage of common cells among 2 or more DTMs for the same area?

I have a study area and 6 different DTMs for that area from different sources and I would like to know the percentage of pixels with the same value. I suppose I will have to extract some statistic and ...
7
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1answer
2k views

How to get GDAL to create statistics for GTiff in Python

I regularly create my own GeoTIFF rasters with GDAL in Python, e.g.: from osgeo import gdal from numpy import random data = random.uniform(0, 10, (300, 200)) driver = gdal.GetDriverByName('GTiff') ds ...
6
votes
4answers
1k views

How to sum up pixel values in QGIS?

I need to know the value of the sum of all pixels in a raster. However, in the Statistics section of the Metadata tab in Properties, under Sum of All Cells it always indicates 0.00. I have tried with ...
14
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7answers
2k views

Best spatial statistics software for GIS?

I am searching for spatial statistics software which has many powerful features and supports a GIS interface. Can anyone give me some advice?
3
votes
1answer
600 views

Why are the results from the same data different in ArcGIS vs MS Excel?

I have done some interpolation in Geostatistical Analyst in ArcGIS and I got the Standard Deviation (SD) a bit different from the SD that I calculated in Excel Spreadsheet. What algorithm does each ...
0
votes
1answer
632 views

Testing if shapefiles intersect from a list using intersect: ArcGIS

I am new to programming and scripting in general, so please bear with me. I have generated a list of the location of all the shapefiles for my workplace. The files are all placed in folders, no ...
12
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5answers
4k views

Get Raster Values from a Polygon Overlay in Opensource GIS Solutions

I have two layers. A polygon-shape-layer with many tiles and a raster-layer containing CORINE 2006 land cover with many categories in a colourmap. I want to obtain for each polygon in the shapelayer a ...
7
votes
4answers
6k views

How to calculate raster statistics for polygons?

how can I calculate sums, averages etc of raster-points (multi-band) per polygon of a vector-layer. I was told that this is called "zonal statistics". I tried that with QGIS first. There is a way to ...
0
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0answers
61 views

How to calculate sums for all fields in a table? [duplicate]

Possible Duplicate: are there any methods can choose all field and make the SUM for each fields or I must do it one by one? Are there any methods that can calculate the summary statistic ...
5
votes
2answers
2k views

Frequency, summarize tool options of ArcGIS for Desktop?

I'm looking for some general frequency, summarize tool. What I basically want is some tool like the summarize tool in ArcGIS (right click in the attribute table> summarize) that runs on all attributes ...
4
votes
1answer
630 views

How to use/interpret/visualise a distance matrix with unknown coordinates?

How would you go about using a distance matrix where points have no coordinates, i.e. what useful statistics can be made and how to visualise it in some useful way?
6
votes
1answer
113 views

How can I generate a range of pantones for a map?

When I am given a map (or make one...) I often like to get an idea of the range of colours present. One thing this does is it allows me to quickly visualize contrast (helps build maps for colour blind ...
4
votes
3answers
1k views

Calculate neighborhood statistics for polygons?

I've been searching around for the answer to this (including here) and have yet to find it. I'm interested in finding out how to calculate a 'neighborhood sum' for vector, polygon data. I am aware ...
8
votes
2answers
411 views

How can I find the median column in a database?

I have data on period of construction for dwellings in dissemination areas. I have transferred this data to my study areas and would like to determine the median period of construction for each study ...
10
votes
3answers
443 views

How is margin of error reported on a map?

When reporting estimates you should always include the margin of error. There are conventional ways of reporting margin of error in a table, text or graph. But, how do you report margin of error for ...
3
votes
2answers
296 views

Performing statistical analysis of buffers?

I am doing a buffer analysis of incinerators and looking at the output areas within those buffers, is there a way of doing a statistical analysis of several buffers to see if there is a significant ...
2
votes
2answers
654 views

How to creat a graph from a Field values (VBA_ArcObjects)

I have a combobox that shows all fields of a shapefile. I want to get these values programmatically in a label--Count, Minimum, Maximum, Sum, Mean, Standard Deviation--and populate a graph of the ...
11
votes
4answers
522 views

Math and Stat for GIS and Computing

I am planning to do an advanced program in spatial science and engineering. It states as a requirement in the program, that the student should have a through understanding in math and statistics. So ...
3
votes
2answers
760 views

How can I track/graph arcserver usage statistics?

I’m currently using the ArcGIS Server Properties dialog in ArcCatalog to periodically check the usage statistics for our services. I’d like to be able to chart those to get a big picture view of ...
6
votes
2answers
2k views

Is it possible to access ArcGIS's table operations “Summarize…” and “Statistics…” in python?

ArcGIS has a few nifty table tools, including Summarize and Statistics. Is there a way to access them through arcpy, or will I have to hack my own methods via math and lists?
6
votes
1answer
1k views

ArcGIS median value from a layer

I've been hunting around ArcGIS 9.3 and having no success at finding a tool/function that can give me the median (not the mean/avg) tabular value of a spatial database. For example, if I have a data ...