Questions tagged [tpi]
The tpi tag has no usage guidance.
8
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TPI calculation by PDAL [closed]
Is there a convenient way to calculate the topographic position index by PDAL?
I have LAS file and what I do is iteratively for every point calculate the TPI. The coordinate information I take from ...
2
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1
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Calculate TPI for irregular DEM
When I use SAGA's Tool Topographic Position Index (TPI) or Tool TPI Based Landform Classification (in QGIS or SAGA itself) on a rectangular DEM the results are as expected but when I try them on a DEM ...
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quite different results in spatialEco::tpi with circular and rectangular window
In R, I have an elevation raster. I want to calculate the topogographic position index using the spatialEco::tpi function. The CRS of the elevation raster is "+init=epsg:5677"; the CRS unit ...
- 1,041
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Stripes in TPI from SRTM 30 DEM
The TPI is calculated with a 150 to 300m annulus in Google Earth Engine.
The underlying Elevation-Data from SRTM does not show such striped.
I did use raw SRTM from GEE for elevation, no reprojecting ...
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Using SAGA GIS for TPI classification?
I processed one country with TPI, and I got a certain Landforms classification of terrain.
(Topographic Position Index (TPI) calculation as proposed by Guisan et al. (1999)).
When I processed only one ...
- 2,385
2
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How to merge pixel values to the nearest maximum value based on area in a classified raster?
We have a raster image with 9 discrete values. Generated the image using SAGA's Terrain Analysis -> Morphometry -> TPI classification technique. Now, like to merge pixels which occupy certain area (...
- 1,421
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3
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How to conduct logistic regression between two rasters [closed]
I have two rasters. The first raster is a region showing sinkholes(depressions) of the region(cell values are 1 for sinkholes and 0 for non-sinkhole cells). The second raster is the TPI(Topographic ...
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Will Topographic Position Index (Tpi) not work in scattered raster layers?
I have a non-continuous elevation raster layer and want to use tpi in the
spatialEco package in R.
The elevation raster is in EPSG:5677 and looks like this:
I always get this (to me) rather cryptic ...
- 1,041