NSIDC坐标转换软件
资源内容介绍
NSIDC坐标转换软件 # NSIDC Polar Stereographic Projection lon/lat conversion: polar_convertPython functions for converting polar stereographic coordinates.This repository contains conversion functions between longitude/latitude and generic x,y (km) coordinates. There are also conversion functions betweenlongitude/latitude and i, j grid coordinates for specific datasets for AMSR-Eand SSM/I.## Level of Support<b>This repository is fully supported by NSIDC.</b> If you discover any problems orbugs, please submit an Issue. If you would like to contribute to thisrepository, you may fork the repository and submit a pull request.See the [LICENSE](LICENSE) for details on permissions and warranties. Pleasecontact nsidc@nsidc.org for more information.## Requirements* Python 3.6 or higher (tested with 3.6.7 and 3.9.7)* [`numpy`](https://numpy.org/) (python library)These requirements are also included in the provided `environment.yml` file,which can be used with [conda](https://docs.conda.io/en/latest/) to install therequirements into a `conda` environment.## InstallationTo install `polarstereo-lonlat-convert-py`, clone this repo and then run:```pip install --editable /path/to/cloned/polarstereo-lonlat-convert-py```This will install the `polar_convert` package in an 'editable' development mode,allowing you to make changes to the source code in`/path/to/cloned/polarstereo-lonlat-convert-py`. See [pip'sdocumentation](https://pip.pypa.io/en/stable/cli/pip_install/#install-editable)for more information.## UsageSee the docstrings for individual functions in[`polar_convert.py`](./polar_convert/polar_convert.py) for details. Thefunctions defined in this file can be used in your own projects.### `polar_lonlat_to_xy`Convert from geodetic longitude and latitude to Polar Stereographic (X, Y)coordinates in km. Functional equivilient of[`mapll.for`](https://github.com/nsidc/polarstereo-latlon-convert-fortran/blob/main/locate/mapll.for).```>>> from polar_convert.constants import NORTH>>> from polar_convert import polar_lonlat_to_xy>>> longitude = 20 # longitude in degrees>>> latitude = 80 # latitude in degrees>>> true_scale_lat = 70 # true-scale latitude in degrees>>> re = 6378.137 # earth radius in km>>> e = 0.01671 # earth eccentricity>>> hemisphere = NORTH>>> polar_lonlat_to_xy(longitude, latitude, true_scale_lat, re, e, hemisphere)[370.2450347527368, -1017.2398726483362]```### `polar_xy_to_lonlat`Convert from Polar Stereographic (x, y) coordinates to geodetic longitude andlatitude. Functional equivilent of[`mapxy.for`](https://github.com/nsidc/polarstereo-latlon-convert-fortran/blob/main/locate/mapxy.for).```>>> from polar_convert.constants import NORTH>>> from polar_convert import polar_xy_to_lonlat>>> x = 370.25 # x coordinate in km>>> y = -1017.24 # y coordinate in km>>> true_scale_lat = 70 # true-scale latitude in degrees >>> re = 6378.137 # earth radius in km>>> e = 0.01671 # earth eccentricity>>> hemisphere = NORTH>>> polar_xy_to_lonlat(x, y, true_scale_lat, re, e, hemisphere)[20.000244645773623, 79.99998329186566]```### `polar_lonlat_to_ij`Convert from longitude and latitude to NSIDC Polar Stereographic I, J (grid)coordinates.```>>> from polar_convert.constants import NORTH>>> from polar_convert import polar_lonlat_to_ij>>> longitude = 45 # longitude in degrees>>> latitude = 85 # latitude in degrees>>> grid_size = 6.25 # in km>>> hemisphere = NORTH>>> polar_lonlat_to_ij(longitude, latitude, grid, hemisphere)[703, 936]```### `polar_ij_to_lonlat`Convert from NSIDC Polar Stereographic I, J (grid) coordinates to longitude andlatitude.```>>> from polar_convert.constants import NORTH>>> from polar_convert import polar_ij_to_lonlat>>> i = 10 # `i` is an int representing the x grid coordinate>>> j = 200 # `j` is an int representing y grid coordinate>>> grid_size = 12.5 # in km>>> hemisphere = NORTH>>> polar_ij_to_lonlat(i, j, grid, hemisphere)[183.02869857834057, 45.89915728375587]```## DevelopmentSee [DEVELOPMENT.md](./DEVELOPMENT.md) for information on how to contribute tothis python code.## LicenseSee [LICENSE](LICENSE), unless otherwise stated in the README file with each subdirectory.## Code of ConductSee [Code of Conduct](CODE_OF_CONDUCT.md).## CreditThis software was developed by the NASA National Snow and Ice Data Center Distributed Active Archive Center.Author: Chris Torrence, September 2019