Changing the values of the cells in a raster.

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3
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1answer
1k 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
110 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
46 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
120 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
357 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
335 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 ...
5
votes
4answers
3k 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
1k 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
981 views

Reclassifying Rasters Error 001100 Failed because no statistics are available

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
198 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
574 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
4k 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 ...
9
votes
2answers
3k 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
231 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
201 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
762 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], ...
7
votes
3answers
3k 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
198 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
537 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
98 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
1k 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 ...
4
votes
1answer
274 views

Reclass all values < 0 to -9999 in PostGIS

I have a tiled raster in a PostGIS table and I would like to change the value of all pixels which have values less than 0 to -9999. How should I do this? I suspect it involves ST_SetValue and ...
6
votes
2answers
4k views

Reclassify raster values of 9999 to NoData, leaving all other values alone, in ArcGIS Desktop?

I have a raster in ArcGIS which has a number of cells with the values 9999, showing that the data could not be generated for that cell. I want to convert all of these 9999 values to NoData, so that ...
4
votes
1answer
3k views

ReClassify Vector Data Between Values using ArcGIS Desktop?

I would like to be able to take all values between 1 and 10 and have a field define them as 1, and all values between 10 and 20 and set them to 2, how do I do that with vector data? I read how to set ...
11
votes
5answers
10k views

How to perform Raster Reclassification in QGIS?

Is there a way to do reclassify a raster image to Qgis? In Arcgis you can do that in Spatial analyst Tools→Reclass→Reclassify Any ideas?
6
votes
2answers
835 views

Raster to Vector: Displaying classes in Vector Layer - GRASS GIS

I use Maximum Likelihood classification to classify Landsat image into two landuse classes - one of my interest and rest including all others. Inorder to assess the accuracy I export it in vector ...