mask

How to make binary mask of large .tif file fast using .shp file with polygons (GPS coordinates)? Question: I have a large .tif file (~24 Gb, more, than RAM could store) (Similar question: https://rasterio.readthedocs.io/en/latest/topics/masking-by-shapefile.html) (Method from library: https://rasterio.readthedocs.io/en/latest/topics/masking-by-shapefile.html) But I’m searching another faster solution. Maybe I should create numpy array with zeros and add polygon …

numpy.all strange behaviour Question: In the following code, I try to generate a mask on an image. The mask should only be true where the image (originalFormat, ndarry with shape [720, 1280, 3]) has a specific value (segmentId, nd array with shape [3,]). Here’s a small part of the code as minimal example: originalFormat = …

How to extract coordinates falling in a bbox from a geopandas data frame? Question: I have a geopandas dataframe with coordinates and long with data frame I have a bbox. Now I want to apply the bbox on the data frame and extract the coordinates that’s falling in that bbox. I tried using gpd.clip to …

What is the fastest way to filter a pandas time series? Question: What is the fastest way to filter a pandas time series? For now I use boolean masking to filter the time series ts: import time from datetime import datetime import pandas as pd import statistics # create time series idx = pd.date_range(start=’2022-01-01′, end=’2023-01-01′, …

Replacing ones and zeros in a 2D numpy array with another array? Question: I have a simple problem that I am trying to solve using numpy in an efficient manner. The jist of it is that I have a simple 2D array containing ones and zeros representing an image mask. What I want to do …

How can I remove the rows of my dataset using pandas? Question: Here’s the dataset I’m dealing with (called depo_dataset): Some entries starting from the second column (0.0) might be 0.000…, the goal is for each column starting from the 2nd one, I will generate a separate array of Energy, with the 0.0… entry in …

Fast way to iterate and apply condition thought dataframe Question: I have a large dataframe such as below: vehicle id delta 0 0 0 1 0 20 2 0 40 3 0 400 4 0 10 5 1 0 6 1 10 7 1 500 8 1 10 9 1 10 10 1 100 11 …

Reconstructing image from mask coordinates Question: I have a Boolean mask (i.e. mask1) in a Numpy array. Its shape its as follows: Then, I have the following code to extract the x and y coordinates of all the pixels within that mask xy_coords = np.flip(np.column_stack(np.where(mask1 > 0)), axis=1)#getting coordinates of pixels within the mask For …

Pandas select rows with smaller index Question: Here is I think a simple question, But I can’t find an answer. I’m trying to set a few rows from a dataframe using a mask of a mask. but I get an "Unalignable boolean Series provided as indexer" error. Here is a small example: import pandas as …

mask and apply numpy where function to a vector in c++ Question: I’m using C++ and want to combine the masking of a vector and the search for the indexes where a condition is verified, similarly to the numpy where function. Here’s an example: std::vector<int> id = {61, 66, 68, 80} std::vector<int> val = {0, …