Changing the values of the cells in a raster.

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5
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1answer
109 views

When to use Con or Reclass

This question was stimulated by a discussion between WhiteBox and myself. Both Reclass and Con (i.e. a conditional evaluation tool) are examples of tools that implement a Switch statement or nested ...
1
vote
1answer
24 views

How to reclass aspect raster to float values

So I have an aspect raster that was created from a DEM. I'm trying to reclassify it using python, but I'm running into some issues. Here's the setup: I need to reclassify values in the aspect raster ...
2
votes
2answers
57 views

Reclassify rasters using GDAL and Python

Using @SS_Rebelious very useful answer, I am trying to reclassify rasters using GDAL and Python. I have a grayscale raster (with values ranging from 0 to 255) and I want to reclassify it to a binary ...
1
vote
1answer
47 views

Reclassification of raster surface using ArcGIS for Desktop?

I have a raster surface with values ranging from 0 -100. I want to create a categorical classification (percentage categories of 5%, e.g. 0-5%, 6-10%...) and reclassify my surface into these ...
1
vote
1answer
50 views

Reclassify says Unique values cannot be obtained from raster, using values from dialog?

I am using ArcGIS 10.2. Whenever I reclassify a raster layer I get the following message:"Unique values cannot be obtained from raster, using values from dialog". This does not prevent be from ...
1
vote
1answer
41 views

ArcGIS Raster Calculator output raster has one band but cannot build attribute table?

I built a raster using the raster calculator of ArcGIS 10.1 for Desktop. The properties of the output raster ("usle_1") indicate that this raster has one band. There is no attribute table but I ...
2
votes
2answers
45 views

Merge classes using Reclassify in python

When I run the Reclassify tool from arcmap 10.1 and assign a 1 to each of the crop types it combines them into one class. However, when I try to recreate this in python it does not merge the crop ...
2
votes
2answers
49 views

Reclassify a rasterList and sum the reclassified value from each Pixel

I'm trying to write a script in arcpy which reclassified a List of Rasters. This rasters are made by another tool before so there is already a loop. Actually I get the error 000582 and before this ...
1
vote
1answer
51 views

How to make reclassified raster layers automatically display break values in their attribute tables?

I am using ArcGIS 10.2. I have many raster layers which I need to reclassify (using the quantile method), I Also need to know the break values of these reclassifications. I know that the break ...
3
votes
1answer
39 views

Why is the quantile reclassification method yielding classes of vastly different cell counts?

I am trying to reclassify many euclidean distance layers (which are based on lines) each into 10 classes of equal area. When I attempt to do this, using the quantile reclassification method, some ...
0
votes
0answers
43 views

How to reassign the values of a raster, based on the pixels of the raster beneath it?

In ArcMap 10.2.1, I have two rasters. Raster1 shows the extent of a habitat, and each pixel contains a categorical value for its land cover type (values 1-3). Raster1 has the smaller spatial extent of ...
2
votes
1answer
36 views

strange banding in output raster after weighted overlay

I am trying to conduct a weighted overlay. I have two rasters, one is a continuous slope raster that I reclassified to have 6 classes (8bit signed integer), and one is an elevation raster that I also ...
1
vote
2answers
91 views

batch reclassify rasters with different elevation ranges

I have about 500 elevation rasters, and I would like to use modelbuilder with an iterator to reclassify each raster into distinct elevation ranges (0-1m, 1-2m, 2-3m, 3-4m, 4-5m). I believe my problem ...
0
votes
2answers
109 views

Reclassify many rasters in ModelBuilder

How do I reclassify many rasters in ModelBuilder when each raster has its own unique values? For example, when you create a model in ModelBuilder and you add the Reclassify tool you may want to ...
0
votes
2answers
31 views

Reclassifying “service area” in ArcGIS Desktop?

I have created service area from few point, and now I would like to reclassyfy it, but when i try to do it I can see the message: ERROR 000864 Input raster: The input is not within the defined ...
1
vote
1answer
104 views

QGIS Slope Classification Issues

I am very new to QGIS for the primary purpose of creating a slopes layer so we know where slopes are above 15% or 20% or whatever we finally decide. I have used our DEM to create a slope geotif and ...
2
votes
0answers
44 views

Is it feasible to reclassify a raster which has been resampled/smoothed for display purposes?

Background: I have a Google Earth KMZ file which shows ground movements after an earthquake, arranged into discrete classes: From the KMZ file I'm able to download the original PNG images, which ...
1
vote
0answers
15 views

Creating Training Pixels in GIS [closed]

I have a map that I've built up. It contains an aerial photo for the background (raster) and it has layers of flight paths of birds on top of it. I want to: 1) classify each pixel based on whether ...
0
votes
0answers
22 views

distance surface with qgis on a binary raster map [duplicate]

I'd like to make a distance surface from a binary map in QGIS. I've got road network in a raster format where value 1 means road, 0 means anything else. How can i reclassify the map which indicates ...
0
votes
0answers
61 views

How to set raster values to NULL?

how can I define values to null? I tried it with the processing reclassify tool but I always get an error log (cannot open the result shape...or something like that).
0
votes
0answers
35 views

RemapValue Usage

I successfully produce and empty cost raster at the end of this script. I am fairly confident it has something to do with RemapValue parameters? Does anyone know why my out put cost distance raster ...
-1
votes
1answer
108 views

IF-Statement in Field Calculator [closed]

I want to use an IF/ELSE-Statement to define a field in the attribute table of my raster. Therefore I have a field "VALUE". The condition should be: If "VALUE" < 4 ...then use die field "A".....if ...
2
votes
3answers
147 views

How to reclassify only a part of a raster but keep the rest unchanged (ArcGIS or R)

I'm trying to reclassify only a certain part of a raster...not the entire raster. Here's the problem. I have a LULC raster of the entire US. There are some issues with the raster that I want to ...
0
votes
1answer
38 views

ArcGIS difference reclassify tool properties symbology

Is there a difference between the reclassify tool and just changing the ranges of a layer within the properties>symbology?
2
votes
2answers
193 views

How to programmatically change raster symbology after reclassification?

I have created a code in Python that I will use for a custom tool in ArcGIS, the code will create a Eucledian Distance of 6000m around a point and Reclassify the distance from 0-2000, 2000-4000, ...
2
votes
1answer
161 views

How to use reclassify tool in ModelBuilder?

I have a model which buffers line features by a variable and then rasterizes them. I then need to reclassify before I am finished processing. My issue is that I cannot access the values to reclassify ...
3
votes
1answer
289 views

How to use raster calculator in ModelBuilder to batch reclassify hundreds of rasters?

I'm not sure what the problem is here. I'm attempting to use iterate by raster to feed all the files through a simple map algebra expression (I'm looking at data that indicates probability of ...
2
votes
1answer
257 views

How to reclassify a raster (tiff) with multiple bands?

i have a raster file containing information about the windspeed average for the year. My purpose is to reclassify the 15 classes based on their rgb-composite. The color is the only information given. ...
1
vote
0answers
175 views

Saga Reclassify grid problem

I am using Qgis 2.1 ver. 5f5cd4c (64 bit version on win7 64) OSGeo installed. I was trying to reclassify a DEM in EPSG:32614. I used the SAGA's Reclassify algorithm in the processing toolbox. I ...
3
votes
1answer
589 views

How to reclassify raster inside polygon mask, leaving values outside as they are?

I am in the final stages of a landcover classification and need to reclassify thematic raster values that are inside different polygon masks, while leaving the values outside as they are. Can I do ...
0
votes
1answer
98 views

Integer rasters referring to the same scale

I'm using ArcMap 10. I want to display the area of simulated avalanches. I want this area to be divided in different colors depending on the thickness of the deposit. I managed to do that. But I want ...
0
votes
0answers
45 views

How to reclassify raster data on a scale of 0-1? [duplicate]

I have various raster layers generated after using euclidean distance tool. How can I reclassify them on a scale of 0-1 instead of 1-10, etc?
1
vote
1answer
107 views

Global DEM and country borders

I am trying to split up the world into 2 categories based on elevation (below 2000m and above 2000m) while still including a country identifier. So in the end, I would like to have 2 types of units ...
1
vote
0answers
252 views

Reclassifying a raster based on values in another raster

I am attempting to create a new raster based on the values of two rasters I have already created. I am using ArcGIS 10.1 Raster1 is an area with my true values. Raster2 was created by reclassifying ...
1
vote
1answer
199 views

Tables within the Reclassify tool- what is it, where is it?

ArcMap 10.1 here. I have a raster set I'm looking to reclassify. The field I need to re-classify is currently a string of words like "Thing 1" and "Thing 2" and I'm going to set them to be 1 and 2. I ...
3
votes
2answers
2k views

How to reclassify a float raster?

I have three rasters which represent distance (in metres) from certain things (bus stops, parks, libraries). I would like to reclassify these rasters so that they get integer values based on the ...
1
vote
1answer
742 views

Multiple reclassification using RasterCalc in QGIS [duplicate]

Is there any way to perform multiple reclassification using RasterCalc? For example reclassifying value 1 to 100 in map Map can be written as: eq([Map]@1, 1, 100) But if there are multiple values ...
1
vote
2answers
556 views

Problem Reclassifying Rasters

I need to reclassify some vector data which was made from Euclidian distance from points and lines. So after getting the Euclidian distances, I tried to run reclassify, but got: Error 001100 Failed ...
2
votes
1answer
181 views

How to reclassify grey scale tiff in qgis

I downloaded a raster image of the sea floor age. The values in band 1 ranges from -32768 to 32767. I need to reclassify it to no. of million of years to make sense of the data. How can I do so? I try ...
0
votes
2answers
427 views

How do you use 'reclass' in GRASS?

It could be user error, but for some reason, the reclass tool is just hanging and hanging... QGIS 1.8 Compiled against GDAL/OGR 1.9.2 Ubuntu 12.04.1 Running the tool from the Sextante toolbox Input ...
1
vote
1answer
3k views

reclass, raster calculator

I'm trying to apply seperate equations for different land types. I have created a raster containing only the land type I'm interested in. I then reclassed the values to '0'. My plan was to use the ...
8
votes
2answers
2k views

How to reclassify a very large land cover dataset?

Consider the NLCD2001 Land Cover dataset for Alaska (download link). I need to reclassify this dataset so that only pixels of value 41, 42, and 43 are preserved; all other pixel values should become ...
3
votes
1answer
145 views

How to get the “absolute value” of a raster cell in QGIS?

I have a raster map (-100 to +100) and I need to get all the minus values as absulute values (-100=100; -99=99...). How can I do this? Is it something like reclassify?
2
votes
0answers
199 views

Reclassifying a field in vector files in ArcGIS [duplicate]

ArcGIS has a reclassify tool that works with Raster files only. Is it possible to have the same functionality for a vector file? On the basis of one of the fields in a feature class, the tool ...
3
votes
1answer
497 views

Issues with arcpy.sa.Reclassify

I have a raster file with classifcation codes, and want to reclassify valid codes to 1, and all others to 'NoData'. RMAP2 = arcpy.sa.RemapValue([[3.2, 1], [4.1, 1], ...
6
votes
2answers
2k views

How to change null values raster values to 0 in QGIS?

I need help... I'm having problems with QGIS. I have some rasters that appear to have null values, even though I reclassified them to obtain a boolean raster :( How can I change the NULL values to 0?
1
vote
0answers
184 views

Reclassify ESRI raster using variables from a SQL Server table (connecting with pyodbc)

I am trying to reclass a raster file (representing vegetation and land cover types) using values stored in a SQL Server Express table. I have a set of ~400 species records in the table, with each row ...
2
votes
1answer
456 views

Creating a constant elevation raster with multiple attributes

Is it possible to create a raster with a constant value with multiple attributes? Such as: rowid value count Name 1 630 36000 Forest 2 630 75000 Anthro 3 630 2600 ...
4
votes
1answer
89 views

What proportion of the 240m area sensed by MODIS must be forest before it is defined as forest?

MOD12 is a MODIS product at 240m resolution. Landsat produces 30m resolution products, which I resampled to 240m resulting in a raster of proportion forest cover in each 240m pixel (based on the mean ...
4
votes
1answer
942 views

How to reclassify in Rastercalc?

I now need to reclassify, I'm using rastercalc... but I can't get the syntax right!! I need that values >0 become 1 I found this example... eq( [relief]@1, [mask]@4, 150 ) so I tried: ( [raster A ...