Posted on February 23, 2023 (Updated on July 10, 2025)
Calculating distortion on Equirectangular Projection
Hiking & ActivitiesWhat is the formula for equirectangular projection? The top figure, called the equi-rectangular projection is perhaps the simplest of all map projections; its formula is T(ϕ, θ)=(θ, ϕ). The other is Lambert’s equal area cylindrical projection; its formula is T(ϕ, θ)=(θ, sin(ϕ)). Is there distortion in a conformal projection? A map that preserves shape is
Posted on February 23, 2023 (Updated on July 10, 2025)
Creating snow cover frequency map in Google Earth Engine
Hiking & ActivitiesHow do I create a NDVI map in Google Earth Engine? Calculate NDVI from Recent Sentinel Satellite Imagery in Google Earth Engine Summary. Get started in Earth Engine (new users) Import Sentinel-2 Imagery within your study area. Calculate NDVI from the Sentinel-2 imagery. Select the Most Recent Image. Add the Most Recent NDVI Image to
Posted on February 23, 2023 (Updated on July 10, 2025)
Local ENU point of interest to ECEF
Hiking & ActivitiesHow to convert ECI to ECEF? In general you will need 4 steps to convert from ECI to ECEF: Calculate earth’s precession. Calculate earth’s nutation. Account for earth’s rotation including UTC-UT1 offset. Account for polar motion. Convert to lan/lon if desired. What are enu vs ned coordinates? It consists of three coordinates: one represents
Posted on February 23, 2023 (Updated on July 10, 2025)
Getting slope from DEM.tif using Spatial Analyst
Hiking & ActivitiesHow is slope calculated from a dem? Create a slope map from the DEM layer. Navigate to System Toolboxes > Spatial Analyst Tools > Surface > Slope. Select the output of the Topo to Raster tool as the input raster. Specify the location of the output raster. Select the output measurement. Click OK. A slope
Posted on February 23, 2023 (Updated on July 10, 2025)
Calculating the mean elevation of a DEM in QGIS
Hiking & ActivitiesHow to get elevation data from DEM in QGIS? Method Ensure that DEM and 2d_zsh line layer files are opened, and the Point Sampling Tool plugin has been installed (Plugins >> Manage and Install Plugins >> Point Sampling Tool) Convert line vertices to points, using the preferred method described in the QGIS Convert Lines to
Posted on February 23, 2023 (Updated on July 10, 2025)
Suppress warnings in Python/OGR
Hiking & ActivitiesHow do I stop user warnings in Python? If you want to stop the process for warnings like exceptions, set action of warnings. simplefilter() to ‘error’ . How do I turn off NumPy warnings? We will use “numpy. seterr(all=’ignore’)” to suppress all floating-point warnings. How do I turn off warning messages in R? We can