A tool in some GIS software programs for performing algebraic operations on rasters.

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Raster Calculator with conditional argument

I am trying to create a binary raster using the Raster Calculator in ArcGIS 10.2. I have a raster with ~20 different values, but I'm only interested in cells where the value = 10. I've been using the ...
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19 views

If statement using QgsRasterCalculator

So in the sequence of my previous question (Can't use Raster Calculator with two different rasters), I am stuck again in my project. With my source rasters, I created 3 different outputs using ...
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1answer
291 views

Calculating Topographic Exposure with Raster Calculator

I need you help trying to calculate Topographic Exposure (TOPEX) on a DEM in ArcGIS. I am trying to figure out wind exposure on a DEM with 25m cells. There is a great blog post where someone explains ...
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21 views

Assigning score to raster based on cell overlap with other raster and field value

I have a set of rasters that I've assigned scores to individually (scored based predominantly on values of other fields). The scoring scale is the same for all rasters, but the factors that determine ...
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15 views

How can i perform area calculations in a raster file?

I would like to know if is possible and how can i calculate all areas or parts of it in one raster? Can i do it using the raster calculator? All help is appreciated, Best regards
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33 views

byte swap a mosaic raster

I'm getting into trouble to byte swap a raster. I'm using two DEM rasters that I mosaic using the function "mosaic to new raster". The new raster I get is called "mosaic". The cell range then shift ...
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1answer
41 views

weighting and combining data sets in Raster Calculator

I`m having problems using Raster Calculator to create a final cost raster. I have to add 7 raster data sets together and multiply each of them with the correct weight. The resulting raster is ...
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1answer
39 views

Animating alterations to DEM based on function using ArcGIS for Desktop?

I've generated a function that alters height values of a DEM based on certain criteria. What I'm looking at doing now is animating this in ArcScene. Is there a way, in ArcGIS, for each frame to be the ...
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3answers
41 views

Raster calculator to create single raster with 4 values from two binary rasters

I have two binary rasters showing habitat suitability (0 = unsuitable, 1 = suitable) under current and future climate scenarios. I am trying to create a raster showing: 0 = cells that are not ...
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3answers
48 views

Can't use Raster Calculator with two different rasters

So, I have several maps like this one: And with the proximity tool and a coastline shapefile I made this output, representing the distance to shoreline: Now, I want to combine both using the ...
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1answer
26 views

Error summing 2 different rasters?

I was trying to sum two different rasters and the final outcome is an error (image attached below)? The main goal is to sum the values of each pixel in those rasters (both raster files have the same ...
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1answer
88 views

How to select a part of a land cover type a certain amount of feet away from another land cover type

I have raster Landcover type Urban combined with Forest all within the county raster perimeter. I want to make a layer of only the forest cells that are more than 500 feet from an urban cell, so that ...
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34 views

changing pixel values using raster calculator Qgis

How could I convert a value of 32767 to a 0 using raster calculator in QGIS?
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37 views

Exclude Raster Cells with Value of Zero in ArcGIS 10.2 Raster Calculator Expression

I need to perform a simple calculation in ArcGIS 10.1 Raster Calculator. I am using a raster layer that contains many cells that have a value of zero. I need to exclude these cells in the expression ...
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1answer
110 views

Issues calculating range with QGIS 2.0 raster calculator

I would like to calculate a simple range using the QGIS 2.0 Raster Calculator, but am getting strange results. I believe I am not using the correct syntax. To get all values between .003-.5, I ...
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1answer
143 views

Cause of ArcGIS Raster Calculator Parsing error <type 'exceptions.SyntaxError'>: invalid syntax?

This is my first attempt at much code in the raster calculator of ArcMap 10.0, but I think I'm close. I have nine rasters (A-I below) and want a new raster with value = 1 where any of the rasters ...
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1answer
16 views

Rastercalc.py and Rastercalcengine.py

Is there any examples on how to use the rastercalc.py or rastercalcengine.py? And what are the purpose of these python module? Are these modules the same with gdal utilities which can be run in ...
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1answer
89 views

How to subtract out the slope (in general) of a DEM?

I'm searching for a solution process to subtract out the slope of a DEM like this: I have a high resolution DEM and want to reconstruct historical/old/not active parts of a river. The problem is ...
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1answer
281 views

Floating point calculations in QGIS

How do I manage floating point calculations in QGIS? I have carried out 3 consecutive calculations on landsat bands. I end up with 32 bit floating point rasters on which I can't carry out a 4th ...
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2answers
76 views

Querying slope data using raster calculator: why are all results true?

I am using ArcGIS 10.2.2. From a DEM, I have created a new raster showing slope using the slope tool. The color scheme was automatically classified into 9 tiers. What I want to do is query this raster ...
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1answer
109 views

How to make a new raster out of two other rasters [duplicate]

I have two raster images, one is the Corine Land Cover for the year 2000 and another one which is the anthropogenic effect on land. The first image reclassified in 9 categories: Artificial surfaces ...
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2answers
278 views

Raster calculation confusion

I need to do some raster calculation, I've been trying to make it work but I am not sure everything is working properly. I need to apply a formula, but I am unsure if I am doing it properly. The ...
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1answer
739 views

Problem with raster calculator [closed]

When working with raster calculator there is an error 000539? The program failed to create a common raster map. I don't know what to do. I did the same in school without any problems. But now, on my ...
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1answer
185 views

GRASS 7 - raster calculator “and”

I am struggling with one thing in the raster calculator in GRASS GIS 7: I want to create a raster_b from raster_a, with raster_a values between >=-0.15 and <=0.15. The raster containing values ...
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2answers
107 views

How to automate creation of toe of slope from DEM?

I was looking for an automated process to "identify" the toe of a slope from a DEM and ran across this ESRI thread and technique: I am at Step 7 but have no idea how this is accomplished. I get it is ...
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57 views

Raster Calculator Syntax - ArcGIS

I'm trying to reclassify a raster based upon two criteria 1. Raster cell on "CBH" is less than or equal to 2 AND "footprint" is not null. Then output raster reclassifies any cell inside this criteria ...
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198 views

Raster vs. Raster Scatter Plot in ArcGIS

I created two raster datasets from the same world view 2 image. One dataset is NDVI, the other is a normalized surface water index (NDSWI). I would like to create a scatter plot for a pixel by pixel ...
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1answer
43 views

Iterate through rasters in subfolders using Model Builder

I have a directory folder of precipitation data; within this folder are subfolders for years 1901-2014. In each of these subfolders are 12 .asc grid files; each file represents a month of the year ...
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1answer
55 views

How to round up/down an pixel value of a raster to a pixel value with 2 decimal places?

I have a raster (DTM) with floating points as pixel value. Now i want to round up/down the pixel values (to its next nearest value) to 2 decimal places. I use ArcGIS (with extensions) and tried the ...
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0answers
45 views

Using iterator in ModelBuilder for groups of rasters

I'm trying to do some raster calculations on Landsat imagery in ModelBuilder. I'm calculating basic indices using Raster Calculator followed by Zonal Statistics. The resulting tables are merged ...
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1answer
1k views

Python syntax error from raster calculator in ArcGIS ModelBuilder?

I am experiencing a problem with the raster calculator in the ModelBuilder under ArcMap 10. I need to combine two layers: a drainage map (issued from a series of previous operations on a DEM) and ...
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1answer
107 views

Calculating average NDVI

I would like to calculate average NDVI values. I have 3 values of NDVI: high:243 low:0 high:243 low:0 high:238 low:0 How can I use a a raster calculator to calculate the average valvue
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39 views

Classify Output Raster as percentage in arcGIS

I have water supply and water demand rasters.They are both of the same cell size and spatial reference. I need the ratio of water use to water demand. Then I want to classify this output in the ...
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33 views

Raster Calculator returning nodata for overlaying cells

I used raster calculator to divide two rasters setting the environment to intersection of inputs. The output has a nodata value in a cell where these two rasters clearly intersect. Any suggestions ...
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2answers
33 views

Remove sections, defined by a line or polygon, from a raster in QGIS

(QGIS 2.6.0 on Windows.) I have created a raster layer of heights using the TIN interpolate function. I also have another raster layer with more accurate information on the height of particular areas ...
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1answer
55 views

Modifying raster values in a zone with a math expression

I'm currently doing an SIG project with the goal of calculating groundwater volumes in chalk and silex residuals aquifers. I have point data of underground water, chalk roof, and floor elevations, as ...
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42 views

Creating a Raster of Road Distance to Point

I am using QGIS 2.6. This question is in two related parts: I'm trying to create a raster of travel time from one point to another point travelling via the road system. Each raster pixel will roughly ...
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1answer
165 views

Why is the result of a raster calculation integer when it should be decimal?

I'm trying to calculate the NDVI using raster calculator, but the result is integer instead of decimal. NDVI = (NIR - RED)/(NIR + RED) The result is normally in the range -1 to 1, but when i tried ...
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2answers
49 views

Using QgsRasterCalculator

I'm trying to make a sum of n rasters and create a new one using QgsRasterClaculator, the problem is, every time the code reaches processCalculation, it makes QGis close and create a dump file. I ...
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35 views

Only run r.neighbors if cell meets criteria

This is my first time using GRASS to work with Rasters, so please excuse my lack of knowledge on the subject. I want to run the GRASS r.neighbors function on cells that meet a specific criteria, ...
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1answer
25 views

Create elevation dependent mean values in ArcGIS RasterCalculator

I have two rasters. Raster1 is a reclassified raster for certain elevation value ranges. Raster2 is an elevation raster too but with gaps. I want to fill the gaps of Raster2 by the median of the ...
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1answer
117 views

Stack sat images and run operation on all

I have about 300 MODIS satellite with different acqusition dates, covering the same area. I am not used to work with so many tiles at once so I ask for advice. I am working with ArcMap10.1 What I ...
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1answer
95 views

Raster Calculator syntax

I have two rasters depicting climate in two periods and I want to compare their values. I want to create a third raster returning: Values of raster 1 are within the minimum and maximum values of ...
2
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1answer
24 views

How to calculate values in a 3*3 matrix using raster calculator?

How to manipulate a raster values in a 3 X 3 matrix.. using raster calculator or any other method e.g. to find out how many cells are there in a 3 X 3 matrix having cell values less than the center ...
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2answers
69 views

How do I get rid of this thin band between raster layers created from TNM?

After hitting my head against the table for many days, I'm humbly presenting myself to the QGIS community. I downloaded 4 IMG files (1/3 arc second, elevation data) from The National Map on the USGS ...
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1answer
73 views

ArcMap 10; Syntax for Minimum operator in raster calculator

I want to linear stretch my raster grid formate having column/rows 3128, 3503 with 30 meter resolution by using the following syntax in raster calculator of arcmap 10.1. ("raster" - ...
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56 views

Normalize the NDVI raster 0-255

NDVI values raster computed by using the band 3 and band 4 reflectance values b4-b3/b4+b3. The output raster is of 32bit type formate although the possible ranges that shows in statistics parameter ...
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88 views

How to Normalize or rescale the NDVI raster image

I have processed my landsat band 3 and band 4 of different years to derive NDVI values the possible values of Normalized difference vegetation index is -1.0 to +1.0. The bands were atmospherically ...
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1answer
182 views

Combining Geological Grids and extruding between them?

I have a situation where I have 3 Geological grids, each showing a different horizon + the Seabed Grid. I need to extrude between these grids in order to make the 3D polygon for the geological ...
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2answers
126 views

QGIS's raster calculator— running as a batch process?

I have a series of raster files (150 or so) that I need to multiply by a baseline raster. Unfortunately, the series of rasters have a different cell size (30mx30m aka .00027777778 degrees x ...