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

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How can I replicate focalmean with focal statistics

Hi I am trying to get rid of some small gaps of no data in my rasters. I would previosly have used focalmean but it is no longer available. I've tried what I expected to work but I'm getting errors. ...
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42 views

count band numbers from multiband raster image

My raster image has 10 bands (10 bands are 10 year), cell values of each one are 1, 2, 3. One is negative anomaly, 2 is no change area, 3 is positive anomaly. Now I want to find how many years out of ...
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29 views

how I can get raster calculator select files with similar names?

The idea is to select raster files with parts of similar name, for example: Filenames (in between many others raster with other names, but in the same folder): 28feb11evs 28feb11evv 28feb11pr ...
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1answer
38 views

How do I input this function to “Raster Calculator” in Model Builder , in ArcGIS 10.2? [closed]

The raster files that function refers are as follows: Precipitation (o “Raster” in figure 1): Variable CN_2S_7ma: Constant CN_8S_7ma: Constant The mathematical function that must be entered is as ...
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1answer
24 views

Using Raster Calculator expression in Python

I've posted about this problem before but I've got a few new questions. So here's the problem. I have two rasters containing bathymetry data: one containing the bathymetry of the sea floor, we'll ...
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34 views

Expressing a Raster Calculator expression with Math Toolset

So here's the problem. I have two rasters containing bathymetry data: one containing the bathymetry of the sea floor, we'll call this raster1, and another containing the difference between two ...
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1answer
22 views

QGIS Treat null as zero in raster calculator

In QGIS - I have an irregularly shaped raster - I wish to clip an irregular area out of it (call it raster A) with that area set to null. I masked the area (vector polygon) I want to remove and used ...
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39 views

What Raster Calculator expression to use? Need to Set Nodata to the overlapping pixels of two rasters (w data example)

Colleagues, hello! For quite a while I`m struggling to make up a map algebra expression in the ArcGIS Raster Calc… On the output I need a single raster with values 0, 30 and nodata (-128). The ...
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1answer
27 views

Multiple CON Expression in ArcGIS Raster Calculator

How can I write the following conditional statement with CON? If ((VALUE = 20 OR IF VALUE=24) then assign value 0, else 1) Con(("Raster1", 0, 1, "VALUE =20")|("Raster1", 0, 1, "VALUE =24"),0,1) I ...
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1answer
32 views

TypeError raster object is not iterable when trying to normalize DEM

In ArcGIS 10.1 I'm trying to normalize a section of a DEM (digital elevation model) from original values to values ranging from 0 to 100. First I clipped the raster DEM with an irregulary shaped ...
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27 views

QGIS RGB image to HSL (Hue Saturation Luminance)

is it possible using QGIS (2.10) on windows to convert an RGB image file to HSL (Hue Saturation Luminance) format. I've seen various formulas for this written in Java however they only seem to be for ...
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1answer
47 views

Reclassify in QGIS using Raster Calculator?

I have downloaded data from the USGS to create a Map for a malaria risk in east africa but my question is only about the actuall Input in the Raster Calculator. I have a RFE Tiff that shows the ...
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1answer
28 views

Edit raster classification manually using polygons - ArcMap

I want to edit the elevation/z values of certain zones on a raster in ArcMap. I followed this example by creating a polygon, assigning a value of 7.5, then converting the polygon to a raster, finally ...
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1answer
18 views

Multiply a stack of floating point rasters( composite raster ) with a constant

I am trying to multiply a floating point stack of rasters (10 layers) with a constant and round up to the next integer. I have the formula RoundUp(10*composite_raster) in raster calculator, but for ...
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28 views

Problem with making raster from Aspect and wind direction data [duplicate]

I know its not correct to ask for work flow, but I am learning by doing and now I don't know how to move on. I'm trying to make new raster which will represent the facing sides of hill around a ...
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24 views

Spatial segregation from a raster of racial distribution in the USA

I am trying to measure the degree of racial segregation at some geographic level (let's say the county level, for simplicity) in the USA. I have a shapefile with these geographic units. To do so, ...
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2answers
184 views

Masking out places with elevation below 5 m from a DEM

I have a DEM of a study region; I want to modify the DEM in order to reflect the coastline outlook when the sea level was 5 meters higher than today. What I have done so far is to use 'Raster ...
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1answer
35 views

script to draw a square where the raster pixels contained within are a certain type and greater than X

I have a raster containing different pixel values and I am interested in having squares drawn around areas that are at least X m^2 and containing at least Y type of pixels. The data looks like this, ...
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53 views

Why does every raster calcuation I try return with NAN values?

I am trying to work with DEM rasters from the USGS using the raster calculator. I have tried to change the units from meters to feet using an expression such as: "ned10m45111h8@1" * 3.28 However ...
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1answer
58 views

Trouble using gdal utilities in python (no output files created)

I am trying to use gdal utilities like gdal_polygonize in python to polygonize my raster image but I'm having trouble understanding the commands. What I mean is in some places the command is of the ...
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22 views

QGIS 2.6 Raster Calculator output is smaller than expected

I have used Raster Calculator to merge several raster layers. The layers were all created using geographical features in the same transect, but as the features are not evenly spread, the raster layers ...
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39 views

How to correctly input complex multiband functions in Raster Calculator?

I'm trying to compute a MTVI2 (Modified Triangular Vegetation Index - Improved) and EVI (Enhanced Vegetation Index) from Landsat 8 imagery. My formulas are as follow (I'm using ModelBuilder): MTVI2= ...
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40 views

How to raster clip in outside in ArcMap?

How to raster clip in ArcMap? But I need 1 raster in outside area. Because 2 raster map. Example: Ras1=Temperature.tif Ras2=Error map.tif Clip command input raster=Ras1 Output Extent= ...
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3answers
41 views

Make all pixel in raster have the same value

I have a raster file with two categories: category 12 (total count=350) and category 14 (total county = 500). The attribute table looks like this: rowid Value Count 0 12 350 1 14 ...
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2answers
111 views

NDVI from Landsat8 LandsatLook images

I have downloaded landsat image from this site and now Im wondering if i can get NDVI index from it. In raster calculator I have only 3 ranges, shouldnt be four? Or am I doing something ...
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1answer
24 views

Mod function in GRASS GIS

What is the equal of ArcGIS Raster calculator "Mod" function (Finds the remainder of the first raster when divided by the second raster on a cell-by-cell basis.) in r. mapcalc in GRASS GIS?
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36 views

Substract 2 rasters with Raster Calculator in ArcObjects (VB.NET)

I'm having a hard time substracting 2 raster with ArcObjects sdk 10.1. I keep getting a nullreference exception at the gp.execute() method, but I can't figure out where the problem is, I recall ...
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65 views

How to compute NDSI in ArcGIS for Desktop?

How do I compute a Normalized Difference Snow Index (NDSI) in ArcGIS's Raster Calculator? I have a Landsat 8 scene (hdf4 format) that contains derived surface reflectance band-by-band. Each band is a ...
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36 views

Generating a predictive map with standardized variables

I have a model from which I am attempting to create a predictive map (in GIS, but I'm aware of some options in R). The response values are constrained to [0,1] using an offset term in the model (see ...
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47 views

Preconditions for subtracting two rasters in arcmap

I have two precipitation rasters, each with a different raster cell size 4.1 x 4.1 km, 4.6 x 4.6 km). The two rasters have the same geographic coordinate system, but different projections. I would ...
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52 views

When subtracting two raster with different cell sizes using raster math, what value is used for smaller cells?

After reading the answer to a similar question (What will happen if we subtract two raster with different cell size using Raster Calculator?), I am still left with a question. When the raster with ...
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2answers
57 views

To select the range of values using Raster calculator in QGIS

I am working on a project where, I need to give ratings for the range of values. I have the following ratings index ratings 0 to 4 4 5 to 8 3 9 to 11 2 12 to 15 1 I am ...
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57 views

Raster Calculator Error 000539: Error running expression: rcexec()

I am using: ArcGIS 10.2 for Desktop Version: 10.2.0.3348 My assignment requires the use of Raster Calculator to run the following calculation "AccessRaster" == 0 & "Slope" >= 2 & "Slope" ...
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38 views

Calculating where the Z values of two rasters intersect

I have several raster layers which are depth horizons, one of these horizons cross cuts the others and I would like to calculate the line along which this occurs. i.e. the line along which the Z value ...
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35 views

Automating Raster Calculator [duplicate]

I am seeing mixed answers on other posts so I thought I would ask here. Is there a way to automate the raster calculator? I am trying to create a series of inundation maps at fine increments. It ...
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67 views

Syntax Raster Calculator

I have never worked with the raster calculator before and I can't solve my problem. There are two raster datasets. One contains roads ( "closed", "in use", "under construction") and the other dataset ...
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27 views

strange raster calculator behavior in QGIS

I used to work with qgis 2.8.1 in Lubuntu and in windows7. Each time I try to multiplicate a map for a number comprise between 0 and 1 (i.e. 0.1) I get a good results on windows OS, but I get a map ...
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1answer
56 views

Does gdal_calc only support 26 input raster files at a time?

In gdal_calc.py, input files are specified with letters A-Z. Here are two files, input.tif and input2.tif, being averaged into result.tif: gdal_calc.py -A input.tif -B input2.tif ...
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45 views

Negative reflectance values from raster calculator computation of GeoEye-1 image

I tried to convert DN values of a pansharpened 2010 GeoEye-1 image into radiance then reflectance in QGIS using raster calculator with the following formulas: (1) L= gain* DN + bias; (2) p = pi* L* ...
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77 views

Preprocessing GeoEye-1 in GRASS iatcorr

I am trying to do a study on land use change using three high-res images of an area from three sources (Quickbird, GeoEye-1, WV-3). I have managed to calibrate the Quickbird data using QGIS raster ...
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1answer
86 views

How to center continuous raster layer by subtracting mean and dividing by standard deviation using QGIS raster calculator?

I'm trying to extrapolate a spatial model to a map in QGIS using the raster calculator. The model predicts the value of a pixel given the environmental conditions at this location (e.g. elevation, ...
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38 views

Using Esri grid format (*.adf) for raster calculation in QGIS?

I got problem with the ADF raster file. In fact I have a land use map in ADF file and I am trying to perform some raster calculation(from raster calculator) but its not working.I have also changed ...
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143 views

QGIS Raster Calculator giving a NaN output

This is my first time using QGIS and I am trying to use it to generate NDVI maps from data captured by my UAV. However when I apply the NDVI formula in the raster calculator using my NIRGB image the ...
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56 views

Remove no-data values from a raster using raster calculator

Can someone please tell me what the formula is to remove no data values from a raster in QGIS? I have a large DEM .tif file and need to remove the no data values. Is it better to use SAGA to perform ...
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81 views

Problem filling raster “gaps” (No-Data cells) by means of different raster

Let's assume I have two (or more) rasters with different resolutions which describe the same area. I would like to combine them - fill "gaps" - use value from the second raster when value in the first ...
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1answer
72 views

How to use the con statement in raster calculator to include a raster as a condition in an existing raster

So, I'm busy doing an assignment where we have to use a Weighted overlay to generate a raster of suitable places to plant crops. I've put all the factors in the weighted overlay and generated my ...
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62 views

How do you use the Raster Calculator in ArcGIS to combine rasters using the Con statement

So, I'm busy doing an assignment where we have to use a Weighted overlay to generate a raster of suitable places to plant crops. I've put all the factors in the weighted overlay and generated my ...
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0answers
62 views

ArcGIS Raster Calculator wont work in main model

I've created a Submodel in ArcGIS, which stretches my rasterdata to new values. The strange thing is, that the model works, if I run it itself - as soon as i implement it in the main model, I get ...
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44 views

How to set floating point raster values to NoData when raster does not have valid statistics

I have a raster with some values of 99999 that I want to set to NoData in Arc 10.2.2. I've tried using the SetNull dialogue box, the SetNull arcpy function, and the Raster Calculator dialogue box as ...
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95 views

Raster Calculator Addition - missing output. ArcMap 10.2.2

I'm currently undertaking multi-criteria analysis and have 5 raster inputs which I would like to add. I have done this before on a previous project with no issues. When I add the 5 layers, only 4 are ...