meta data for this page
This is an old revision of the document!
Useful links and snippets regarding Python and Jupyter notebooks
Modules
- The uncompromising Python code formatter https://black.readthedocs.io/en/stable/ and on Github: https://github.com/psf/black
iPython/Jupyter resources
Quick and dirty
# py3 from urllib import parse parse.unquote("""TheURLString""") # or in py2.7 import urllib urllib.unquote("theURL").decode('utf8')
- Translate coordinate reference system from
*.prj
files to proj4-Syntax as required by QGIS using the gdal python module (via GIS on Stackexchange: import sys from osgeo import osr prjtxt = """PROJCS["your_crs",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["the_prj"],PARAMETER["Central_Meridian",0.0],PARAMETER["False_Easting",0.0],PARAMETER["False_Northing",0.0],PARAMETER["Latitude_Of_Origin",0.0],PARAMETER["Standard_Parallel_1",-10],PARAMETER["Standard_Parallel_2",50],UNIT["Meter",1.0],AUTHORITY["me",123456]]""" srs = osr.SpatialReference() print 'Proj4 is: %s' % srs.ExportToProj4() Proj4 is: <string with proj4 parameters follows>
Pandas
- Invert a single column of a Pandas Dataframe: ``df.col2 = df.col2.values[::-1]`` via StackOverflow
- Joining multiple overlapping column names from multiple dataframes: ``pd.concat(data, axis=1)`` via StackOverflow
- Cross-section indexing of a multi-indexed dataframe - using levels: ``concatdf.xs('MIndexValue', level='MIndexName')`` - via Pandas documentation and StackOverflow
- Pandas merging 101 on StackOverflow.
Stuff related to modules
- Installing a new module in Enthough Canopy Light's distro on Windows: I managed to install the DBF module by navigating to the unzipped content downloaded in the Python console. Then I just typed
%run setup.py install
and the compiled module is then installed in the Canopy'sUser\Lib\site-packages
directory. Easy.