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How to replace raster values in one raster with another?
I want to replace values in raster 1 with those in raster 2 where there is an overlay. meaning that if raster1 has no value, it will use the value of raster2, otherwise it will use the value of raster1. Under the Enviroments… tab you can select your desired extent of the output raster.
How to change the size of rasters in ArcMap?
In ArcMap, run the Mosaic To New Raster geoprocessing tool. For Input Rasters, add both the large and small rasters. Specify the output location, output raster dataset name with extension, pixel type, and number of bands. For Mosaic Operator , if the smaller raster is at the top of the list in Input Rasters, select FIRST; otherwise, select LAST .
How to make a map a permanent raster?
To make this a permanent raster, either right-click the raster layer, click Data, and select the Make Permanent option, or save the map document. 1. In ArcMap, navigate to ArcToolbox > Spatial Analyst Tools > Map Algebra and open the Raster Calculator. 2. In the Raster Calculator, input the following syntax:
Do you have to set pixel type to match raster data?
You must set the pixel type to match your existing input raster datasets. If you do not set the pixel type, the 8-bit default will be used and your output may be incorrect. You can save your output to BIL, BIP, BMP, BSQ, DAT, Esri Grid, GIF, IMG, JPEG, JPEG 2000, PNG, TIFF, or any geodatabase raster dataset.
How to subtract DEM from dams in raster?
If you have the dams in a raster file with the cells that represent the dams having the elevation data and the other cells being nodata, you can subtract the dem from the dams layer in the raster calculator (R2-R1 in Chris’ answer).
Can a raster calculator be used in QGIS?
As gene mentions, the raster calculator can also be used to solve this in QGIS. Note there is the one that comes with QGIS as well as one (RasterCalc) or more plugins available that may have different capablities. There are several ways you could approach the problem with different formulas (such as a conditional statement or diff function).
How to create a new raster in Python?
If so, the Con function will do exactly what you want. Create a “condition” raster that is 1 where you want the values changed to Ras2 and 0 everywhere else. Execute the statements: This will replace Ras1 with your new raster. If you just want to create a new raster, change the string in the save function.
How to use or in a con statement in the ArcGIS raster?
The pages Building expressions in Raster Calculator and Conditional evaluation with CON don’t help, and “or” seems to be keyword that Google ignores…. It is important to know the precedence level of the operators.
Why do you need parentheses in the ArcGIS raster?
Operators with the highest precedence are grouped together first, this is why you need parentheses if you want to force evaluating “>” before “|”. Thanks for contributing an answer to Geographic Information Systems Stack Exchange! Please be sure to answer the question.
How to use conditions in a raster calculator?
Assuming that you already masked your “green” raster with NoData values where you don’t want to replace the “red” values, Then you can use conditions in raster calculator (Map algebra tool). This would be a code like below Which means: if the green raster is noData, then use the value of the red raster, otherwise use “green”.
When to use the red or green raster in the environment variable?
Which means: if the green raster is noData, then use the value of the red raster, otherwise use “green”. In the environment variable, make sure that you set the extent to maximum extent of inputs.