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

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18 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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0answers
20 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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22 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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2answers
532 views

Why does Raster Calculator return GRID ERROR-Unable to open input grid?

I'm calculating Simple Ratio (SR) from NDVI using Raster calculator in Arcgis. Here is expression I wrote in Raster calculator. SR=(1+float[NDVI_apr.tif])/(1-float[NDVI_apr.tif]) But when I ...
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1answer
139 views

QGIS SAGA Raster Calculator [closed]

I am using SAGA --> Grid Calculus --> Raster Calculator on QGIS version 2.6. The formula I am using is: ifelse(gt(a,0), (a), b) where a is my layer with values in a greater extent than that of b. ...
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2answers
84 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
153 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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3answers
38 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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1answer
234 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
351 views

Getting Error 000539 from Raster Calculator?

I am new to Arc and 10.2 but can not seem to figure out why this won't work. Executing: RasterCalculator Con(("SLOPE_SLO.tif" >= .015) & ("SLOPE_SLO.tif" <= .15,1,0)) ...
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79 views

Trouble with reading Leaf area index (LAI) Modis on QGIS

I am having trouble reading my Modis LAI data on QGIS. I imported my Modis hdf files and I used the QGIS raster calculator to apply the scale factor and all I get is a blank gray tile. My goal is to ...
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1answer
313 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
21 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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15 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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45 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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1answer
530 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 ...
3
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1answer
585 views

Help with scripts for processing raster files with the raster calculator in QGIS

I am trying to process some raster files using python scripts in Qgis 2.20, and I have been having trouble finding any documentation on using raster calculator in scripts being run in the processing ...
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29 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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1answer
598 views

Managing sizes of input rasters for raster calculation in ArcGIS Desktop?

To calculate any formula (conditional statements/relational operation etc) in the raster calculator in ArcGIS using two different sources of raster images, I'd like to know input rasters must be the ...
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0answers
22 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 ...
2
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1answer
550 views

How to separate raster bands in ModelBuilder?

I have a simple model that iterates through folders to collect imagery, mosaics them and clips the mosaic to a study area boundary. I need to produce an NDVI from the clipped 4-band mosaic ...
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37 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
43 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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26 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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33 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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1answer
185 views

How can I multiply each band of multiband image by separate scalars using ArcGIS Desktop?

I have an image with 5 bands. I need to multiply each band of this image by different scalars one time (I'm lazy to do it one by one) and then get multiband image as a output. For example ...
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1answer
168 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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33 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 ...
3
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1answer
73 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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62 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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25 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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25 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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1answer
12 views

Use of OTB BandmathX

I have a couple of three-band satellite images that I want to apply an expression to and get a three-band output. The expression is of a simple form: output_pixel= (input_pixel*d^2)/cos e After ...
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63 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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32 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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2answers
4k views

How to standardize raster output from 0 to 100 using raster algebra?

I am working on generating an integrated moisture index based on the following equation: IMI = (hill shade * 0.5) + (curvature * 0.15) + (flow accumulation * 0.35) Iverson et al. 1997 Another ...
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28 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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58 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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0answers
79 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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0answers
184 views

NDVI from QGIS is giving me NaN values

When I use QGIS' "slope based VI calculation" for Landsat 8 IR and Red bands the resulting NDVI and TTVI maps are all NaN values. When I do the NDVI calculation using the raster calculator it looks ...
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0answers
47 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 ...
3
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0answers
110 views

Creating a new raster based on pixel value of original raster using raster calculator but new layer is not evident [closed]

I am trying to create a new raster based on a current raster (w001001 - NVIS) which has one paletted band, with palette values ranging from 1 to 29, with each palette/value representing a vegetation ...
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0answers
38 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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1answer
47 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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0answers
46 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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72 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 ...
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33 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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2answers
39 views

gdal_calc : fails with value 0?

I working to invert values of a one-band tif files (download sample). If i use 254 it works: $ gdal_calc.py -A ./shadedrelief.tmp.tif --outfile=whited.tmp.tif --calc="254*(A>180)" 0 .. 10 .. ...
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29 views

How to extract the raster files from .prj?

I am interested in using Raster Calculator tool for which i need the desired raster files. But i came across a problem i.e. when i converted my vector files to raster and saved them they were saved ...
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1answer
53 views

Python error in Con function

I am trying to add two different rasters using the Con function. I am iterating the raster layer using the for loop to obtain two rasters belonging to the same species and their formats are in grid ...