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

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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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170 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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19 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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21 views

Fill raster “gaps” (No-Data cells) by means of different raster [on hold]

Let's assume I have two (or more) rasters with different resolutions which describe the same area. Since my question is so general, I thought that I will easily navigate answer, but I can't. This is ...
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1answer
217 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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106 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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1answer
459 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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1answer
279 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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17 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 ...
3
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1answer
34 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 ...
3
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1answer
517 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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25 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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52 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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25 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
32 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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1answer
152 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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27 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
48 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 ...
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9 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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26 views

qgis raster calculator unexpected type long

I am trying to do a very simple multiplication of a raster using the QGIS raster calculator but repeatedly receive the following error: Traceback (most recent call last): File ...
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75 views

Merging rasters which overlap using ArcGIS for Desktop?

I need to merge two rasters which overlap, both indicate distance values. I need the output of the merge to result in the shorter/lower distance value. I am using ArcGIS 10.1. I hope it is more ...
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1answer
58 views

How to use the math tool (“times”) in ArcGIS modelbuilder to multiply two raster sets while using an iterator?

I have two sets of rasters (in the same gdb), representing "loss" and "forestmask". I would like to multiply each forestmask raster (value 1 = forest) with its corresponding loss raster (value ...
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2answers
41 views

Combine multiple binary rasters to a single raster

I have 5 different species richness maps which I am trying to join in order to show one cohesive map. Each species raster layer has values of 1 and 0; 1 if the species lives there and 0 if the species ...
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25 views

Where to find QGIS geoprocessing results?

Is there a way to access in QGIS 2.6.1 something like the Geoprocessing Results window found in ArcGIS? The History and Log window in QGIS appears to show the geoprocessing results from SAGA, OTB ...
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755 views

Error 000539 in raster calculator in ArcMap 10 [closed]

I'm having trouble averaging 12 rasters in the raster calculator. I keep getting a 000539 error, which I assume means that the syntax in the equation is bad. The problem is I dont know whats wrong ...
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1answer
294 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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1answer
111 views

ArcGIS Raster Calculator error 000539 ImportError: No module named numpy?

I am running ArcGIS 10.2.1 on Win7 64bit. I have finished doing an NDVI, and after defining a vegetation presence threshold at 0.05, opened the Raster Calculator (via Map Algebra in the Arc Toolbox) ...
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1answer
77 views

Fixing Raster Calculator Error 000539 ImportError: No module named numpy? [duplicate]

I've created 4 hillshades for a particular area to represent the 4 seasons in a year. The equation I now need to use to determine solar insulation is 1000*hillshade/255 in raster calculator. However, ...
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1answer
1k views

Why does Raster Calculator (RasterCalculator_sa) give ERROR 000539 in ArcPy?

I am getting a not executed error for a raster calculator. Here is part of the output: File "C:\projectTemp\FloodAnalysis\floodxsectionanalysis.py", line 107, in makeSeemless ...
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460 views

Raster calculator error 000539 - cannot create weak reference to 'classobj' object

I was - like many times before - trying to clip a raster with the raster calculator (raster * 1 with shapefiles as mask). Now - the following error keeps popping up: ERROR 000539: Error running ...
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1answer
25 views

Error 000539 - Band_# not defined

I'm trying to do an NDVI analysis of a some World View 2 imagery. It seems no matter what if I enter the term Band_# for any of the 8 bands I get the same error.
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1answer
176 views

ArcGIS Raster Calculator fails with Error 000539

I have been using Raster Calculator in ArcMap 10.2, today it started returning error 000539 for all actions. Previously it had worked fine. I have not made any change ot my ArcGIS, Python, or Windows ...
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2answers
45 views

How to automate conversion of raster NoData values?

I am doing the work of change all null pixels to a value of -1 in the raster file X with raster calculator by using following syntax: Con(IsNull("X"),-1,"X") However, I need to do the same work on ...
3
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1answer
55 views

Cell Statistics in QGIS

Cell Statistics in ArcGIS will calculate the mean (or statistic of choice) among multiple rasters on a cell-by-call basis. Can QGIS do this? If so, how?
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1answer
30 views

I want to compare multiple raster layers against each other to identify changes in pixel values over time

I am using LAI values to assess vegetation growth over large areas. I want to be able to identify areas that are doing well and areas that are decreasing based on the changes in pixel values. Ideally ...
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1answer
50 views

Conditional calculation - QGIS Raster Calculator or GRASS r.mapcalculator

Is it possible in QGIS either directly or via plugins to do a raster calculation including an if statement? e.g., if raster1 > 0.3, then raster 1 * raster 2, else raster1 x raster3...something like ...
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34 views

QGIS raster calculator wrong output

I am trying to create a mask from a DEM (SRTM tile) using raster calculator in QGIS. I have performed the same operation in ver 2.6 with no problem but in the current version the output is incorrect. ...
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41 views

Recalculating NDVI from DN with 19 1 channel NOAA Satellite images?

I am working with 19 satellite images (annual mean between 1982-2000) from the NOAA RS. I am supposed to recalculate the DN to NDVI. I know the formula of NDVI = NIR - RED / NIR + RED. However, ...
2
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1answer
1k views

using raster calculator

I have a combination method to combine two raster( raster x and y) . the method is : x+y / 1- min(|x|,|y|) my problem is about "," character .whats the "," means in the method and how can i use this ...
2
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2answers
76 views

Raster calculator - addition

Help!!! What am I doing wrong? I have generated two rasters from vector layers. They cover the same extent and have the same projection (Irish Transverse Mercator) and cell size (5m x 5m). I have ...
0
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1answer
9 views

Implementing GLMMs in ArcGIS

I am looking to create a predictive model in ArcGIS. I have done this previously with glm with poisson distribution and found it relatively straightforward in raster calculator e.g. exp(intercept + ...
2
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1answer
88 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
95 views

QGIS SAGA Raster Calculator

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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49 views

apply gdal to calculate raster that is already in qgis raster calculator

I am using the following code in qgis to calculate some raster.It is not giving the correct result as it is in arcpy.I want to apply same in gdal.Can anyone help me how to use the gdal api.Please give ...
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0answers
22 views

Computing View Distance in One Direction from Point on Elevation Raster in PostGIS?

I'm a software developer just getting into GIS, so please forgive me if I don't use proper lingo, or if I use proper lingo incorrectly! I have a raster of elevation data. For a given point in the ...
2
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1answer
18 views

Combining several raster files generated from polylines

Maybe I'm just missing the point somewhere... I'm working on a path distance analysis, specifiying the cost layer. For this I have built a model, where I have roads and trails, both polylines, that I ...
0
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2answers
55 views

Combine overlapping rasters and include cells with no data

I'd like to combine about a dozen rasters into one raster that contains the "summed" cell values where overlaps occur. In doing so, I need to be able to retain cells that either have no data, or that ...
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2answers
141 views

QGIS raster calculator using abs() function

Is it possible to use the Abs() function in the raster calculator in QGIS? I've tried it, but it didn't work.
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1answer
64 views

Qgis raster calculator not giving output

I want to calculate some result using QgisRasterCalculator and using the code mentioned below.Problem is i am not getting any output raster also if i use this formula in raster calculator it gives ...
4
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1answer
49 views

Raising raster to a power gives no data values

When performing the following operation in QGIS Raster calculator: 10 ^ (("20091201_20100101_chl_modis_malvinas_ns@1" * 0.0000581)-2) I get no dada values for every cell where I should get < 1, ...