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other:python:jyp_steps [2018/02/26 13:19]
jypeter [Matplotlib] Added a ref to zorder
other:python:jyp_steps [2018/09/04 12:43]
jypeter [Matplotlib] added note about colors
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     - [[https://​docs.scipy.org/​doc/​numpy-dev/​user/​numpy-for-matlab-users.html|Numpy for Matlab users]]     - [[https://​docs.scipy.org/​doc/​numpy-dev/​user/​numpy-for-matlab-users.html|Numpy for Matlab users]]
     - [[http://​mathesaurus.sourceforge.net/​matlab-numpy.html|NumPy for MATLAB users]] (nice, but does not seem to be maintained any more)     - [[http://​mathesaurus.sourceforge.net/​matlab-numpy.html|NumPy for MATLAB users]] (nice, but does not seem to be maintained any more)
-  - read the [[https://​docs.scipy.org/​doc/​numpy-dev/​user/​quickstart.html|Quickstart tutorial]]+  - read the really nice [[https://​docs.scipy.org/​doc/​numpy/​user/​quickstart.html|numpy Quickstart tutorial]]
   - have a quick look at the full documentation to know where things are   - have a quick look at the full documentation to know where things are
     - Numpy User Guide     - Numpy User Guide
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        [20, 21, -1, -1, 24, 25, 26, 27, 28, 29]])        [20, 21, -1, -1, 24, 25, 26, 27, 28, 29]])
 </​code></​note>​ </​code></​note>​
 +
 +==== Extra numpy information ====
 +
 +  * More information about array indexing:
 +    * Examples:
 +      * {{ :​other:​python:​indirect_indexing_2.py.txt |}}: Take a vertical slice in a 3D zyx array, along a varying y '​path'​
 +    * [[https://​docs.scipy.org/​doc/​numpy/​user/​basics.indexing.html|Indexing]] (//index arrays//, //boolean index arrays//, //​np.newaxis//,​ //​Ellipsis//,​ //variable numbers of indices//, ...)
 +    * [[https://​docs.scipy.org/​doc/​numpy/​user/​quickstart.html#​fancy-indexing-and-index-tricks|Fancy indexing]] and [[https://​docs.scipy.org/​doc/​numpy/​user/​quickstart.html#​the-ix-function|the ix_() function]]
 +    * [[https://​docs.scipy.org/​doc/​numpy/​reference/​arrays.indexing.html|Indexing (in the numpy reference manual)]]
 +    * [[https://​docs.scipy.org/​doc/​numpy/​reference/​routines.indexing.html#​routines-indexing|Indexing routines]] ​
 +  * More information about arrays:
 +    * [[https://​docs.scipy.org/​doc/​numpy/​reference/​routines.array-creation.html#​routines-array-creation|Array creation routines]]
 +    * [[https://​docs.scipy.org/​doc/​numpy/​reference/​routines.array-manipulation.html|Array manipulation routines]]
 +    * [[https://​docs.scipy.org/​doc/​numpy/​reference/​maskedarray.html|Masked arrays]]
 +      * [[https://​docs.scipy.org/​doc/​numpy/​reference/​routines.ma.html|Masked array operations]]
 +  * [[https://​docs.scipy.org/​doc/​numpy/​user/​misc.html#​ieee-754-floating-point-special-values|Dealing with special numerical values]] (//Nan//, //inf//)
 +    * If you know that your data has missing values, it is cleaner and safer to handle them with [[https://​docs.scipy.org/​doc/​numpy/​reference/​maskedarray.html|masked arrays]]!
 +    * [[https://​docs.scipy.org/​doc/​numpy/​user/​misc.html#​how-numpy-handles-numerical-exceptions|Handling numerical exceptions]]
 +    * [[https://​docs.scipy.org/​doc/​numpy/​reference/​routines.err.html|Floating point error handling]]
  
 ===== cdms2 and netCDF4 ===== ===== cdms2 and netCDF4 =====
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 ==== cdms2 ==== ==== cdms2 ====
  
-Summary: cdms2 can read/write netCDF files (and read //grads// dat+ctl files) and provides a higher level interface than netCDF4. ​Unfortunately, ​cdms2 is only available in the [[other:​python:​starting#​uv-cdat|UV-CDAT distribution]],​ and distributions where somebody has installed ​some version ​of //cdat-lite//. When you can use cdms2, you also have access to //cdtime//, that is very useful for handling time axis data.+Summary: cdms2 can read/write netCDF files (and read //grads// dat+ctl files) and provides a higher level interface than netCDF4. cdms2 is available in the [[other:​python:​starting#​uv-cdat|UV-CDAT distribution]],​ and can theoretically be installed ​independently ​of UV-CDAT (e.g. it will be installed when you install [[https://cmor.llnl.gov/mydoc_cmor3_conda/|CMOR in conda)]]. When you can use cdms2, you also have access to //cdtime//, that is very useful for handling time axis data.
  
 How to get started: How to get started:
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     - the tutorial is in French (soooorry!)     - the tutorial is in French (soooorry!)
     - you have to replace //cdms// with **cdms2**, and //MV// with **MV2** (sooorry about that, the tutorial was written when CDAT was based on //Numeric// instead of //numpy// to handle array data)     - you have to replace //cdms// with **cdms2**, and //MV// with **MV2** (sooorry about that, the tutorial was written when CDAT was based on //Numeric// instead of //numpy// to handle array data)
-  - read the [[http://uv-cdat.llnl.gov/documentation/cdms/cdms.html|official cdms documentation]] +  - read the [[http://cdms.readthedocs.io/en/docstanya/index.html|official cdms documentation]] ​(link may change)
-  - ask questions and get answers on the [[http://​uvcdat.askbot.com/​questions/​|UV-CDAT askbot]]+
  
  
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 Where: [[http://​unidata.github.io/​netcdf4-python/​]] Where: [[http://​unidata.github.io/​netcdf4-python/​]]
  
 +===== CDAT-related resources =====
 +
 +Some links, in case they can't be found easily on the [[https://​uv-cdat.llnl.gov|UV-CDAT]] web site...
 +
 +  * [[https://​uv-cdat.llnl.gov/​tutorials.html|Tutorials in ipython notebooks]]
 +  * [[http://​cdat-vcs.readthedocs.io/​en/​latest/​|VCS:​ Visualization Control System]]
 +    * [[https://​github.com/​CDAT/​vcs/​issues/​238|Colormaps in vcs examples]]
 +  * [[https://​github.com/​CDAT/​cdat-site/​blob/​master/​eztemplate.md|EzTemplate Documentation]]
  
 ===== Matplotlib ===== ===== Matplotlib =====
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     - a Matplotlib //Axis// is a plot inside a Figure... [[http://​matplotlib.org/​faq/​usage_faq.html#​parts-of-a-figure|More details]]     - a Matplotlib //Axis// is a plot inside a Figure... [[http://​matplotlib.org/​faq/​usage_faq.html#​parts-of-a-figure|More details]]
     - some examples are more //​pythonic//​ (ie object oriented) than others, some example mix different styles of coding, all this can be confusing. Try to [[http://​matplotlib.org/​faq/​usage_faq.html#​coding-styles|use an object oriented way of doing things]]!     - some examples are more //​pythonic//​ (ie object oriented) than others, some example mix different styles of coding, all this can be confusing. Try to [[http://​matplotlib.org/​faq/​usage_faq.html#​coding-styles|use an object oriented way of doing things]]!
 +    - it may be hard to (remember how to) work with colors. Some examples from the [[|Gallery]] can help you!
 +      * [[https://​matplotlib.org/​examples/​pylab_examples/​leftventricle_bulleye.html|leftventricle_bulleye.py]]:​ associating different types of colormaps to a plot and colorbar
 +      * [[https://​matplotlib.org/​examples/​api/​colorbar_only.html|colorbar_only.py]]:​ the different types of colorbars (or plotting only a colorbar)
 +      * [[https://​matplotlib.org/​examples/​color/​colormaps_reference.html|colormaps_reference.py]]:​ pre-defined colormaps
 +      * [[https://​matplotlib.org/​examples/​color/​named_colors.html|named_colors.py]]:​ named colors
     - sometimes the results of the python/​matplolib commands are displayed directly, sometimes not. It depends if you are in [[http://​matplotlib.org/​faq/​usage_faq.html#​what-is-interactive-mode|interactive or non-interactive]] mode     - sometimes the results of the python/​matplolib commands are displayed directly, sometimes not. It depends if you are in [[http://​matplotlib.org/​faq/​usage_faq.html#​what-is-interactive-mode|interactive or non-interactive]] mode
     - the documentation may mention [[http://​matplotlib.org/​faq/​usage_faq.html#​what-is-a-backend|backends]]. What?? Basically, you use python commands to create a plot, and the backend is the //thing// that will render your plot on the screen or in a file (png, pdf, etc...)     - the documentation may mention [[http://​matplotlib.org/​faq/​usage_faq.html#​what-is-a-backend|backends]]. What?? Basically, you use python commands to create a plot, and the backend is the //thing// that will render your plot on the screen or in a file (png, pdf, etc...)
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 ===== Graphics related resources ===== ===== Graphics related resources =====
  
 +  * [[http://​journals.plos.org/​ploscompbiol/​article?​id=10.1371/​journal.pcbi.1003833|Ten Simple Rules for Better Figures]]
   * [[http://​seaborn.pydata.org/​|Seaborn]] is a library for making attractive and informative statistical graphics in Python, built on top of matplotlib   * [[http://​seaborn.pydata.org/​|Seaborn]] is a library for making attractive and informative statistical graphics in Python, built on top of matplotlib
     * See also: [[https://​www.datacamp.com/​community/​tutorials/​seaborn-python-tutorial|     * See also: [[https://​www.datacamp.com/​community/​tutorials/​seaborn-python-tutorial|
 Python Seaborn Tutorial For Beginners]] Python Seaborn Tutorial For Beginners]]
-  * [[http://​colorbrewer2.org|ColorBrewer 2.0]] is a tool that can help you understand, and experiment with //​sequential//,​ //​diverging//​ and //​qualitative//​ colormaps+  ​* Working with colors 
 +    * [[https://​matplotlib.org/​users/​colormaps.html|Choosing colormaps]] 
 +    * [[https://​matplotlib.org/​cmocean/​|Beautiful colormaps for oceanography:​ cmocean]] 
 +    ​* [[http://​colorbrewer2.org|ColorBrewer 2.0]] is a tool that can help you understand, and experiment with //​sequential//,​ //​diverging//​ and //​qualitative//​ colormaps
  
  
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 Help on //stack overflow//: [[https://​stackoverflow.com/​questions/​tagged/​cartopy|cartopy help]] Help on //stack overflow//: [[https://​stackoverflow.com/​questions/​tagged/​cartopy|cartopy help]]
  
 +===== Maps and projections resources =====
 +
 +==== About projections ====
 +
 +  * [[https://​egsc.usgs.gov/​isb//​pubs/​MapProjections/​projections.html|Map projections from USGS poster]]
 +  * [[https://​pubs.usgs.gov/​pp/​1395/​report.pdf|Map projections - A working manual (USGS)]]
 +
 +==== Libraries ====
 +
 +  * Projections in vcs
 +  * [[http://​matplotlib.org/​basemap/​users/​mapsetup.html|Projections in basemap]]
 +  * [[https://​scitools.org.uk/​cartopy/​docs/​latest/​crs/​projections.html|Projections in cartopy]]
 +
 +
 +===== 3D resources =====
 +
 +  * [[https://​ipyvolume.readthedocs.io/​en/​latest/​|Ipyvolume]]
 +  * [[https://​zulko.wordpress.com/​2012/​09/​29/​animate-your-3d-plots-with-pythons-matplotlib/​|Animate your 3D plots with Python’s Matplotlib]]
 +  * [[https://​stackoverflow.com/​questions/​26796997/​how-to-get-vertical-z-axis-in-3d-surface-plot-of-matplotlib|How to get vertical Z axis in 3D surface plot of Matplotlib?​]]
 +
 +=====  Data file formats ===== 
 +
 +We list here some resources about non-NetCDF data formats that can be useful
 +
 +==== json files ====
 +
 +More and more applications use //json files// as configuration files or as a mean to use text files to exchange data (through serialization/​deserialization ).
 +
 +//json// files look basically like a **list of (nested) python dictionaries** that would have been dumped to a text file
 +
 +  * [[https://​docs.python.org/​2/​library/​json.html|json module]] documentation
 +  * [[https://​realpython.com/​python-json/​|Working With JSON Data in Python]] tutorial
 +  * example script: ''/​home/​users/​jypeter/​CDAT/​Progs/​Devel/​beaugendre/​nc2json.py''​
 +  * A compact (not easy to read...) //json// file can be pretty-printed with\\ ''​cat file.json | python -m json.tool | less''​
 +
 +==== LiPD files ====
 +
 +Resources for //Linked PaleoData//:​
 +  * [[http://​linked.earth/​projects/​lipd/​|LiPD]]
 +  * [[https://​doi.org/​10.5194/​cp-12-1093-2016|Technical note: The Linked Paleo Data framework –
 +a common tongue for paleoclimatology]] @ GMD
 +  * [[https://​github.com/​nickmckay/​LiPD-utilities|LiPD-utilities]] @ github
 +
 +==== BagIt files ====
 +
 +//BagIt//, a set of hierarchical file layout conventions for storage and transfer of arbitrary digital content.
 +
 +  * [[https://​tools.ietf.org/​html/​draft-kunze-bagit-16|The BagIt File Packaging Format]]
 +  * [[https://​github.com/​LibraryOfCongress/​bagger|Bagger]] (BagIt GUI)
 +  * [[https://​github.com/​LibraryOfCongress/​bagit-python|bagit-python]]
 ===== Pandas ===== ===== Pandas =====
  
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   * The nice and convenient Python 2.7 Quick Reference: [[http://​rgruet.free.fr/​PQR27/​PQR2.7_printing_a4.pdf|pdf]] - [[http://​rgruet.free.fr/​PQR27/​PQR2.7.html|html]]   * The nice and convenient Python 2.7 Quick Reference: [[http://​rgruet.free.fr/​PQR27/​PQR2.7_printing_a4.pdf|pdf]] - [[http://​rgruet.free.fr/​PQR27/​PQR2.7.html|html]]
 +    * A possibly more [[http://​iysik.com/​PQR2.7/​PQR2.7.html|up-date-version]]
 +
 +  * Python 3 [[https://​perso.limsi.fr/​pointal/​python:​abrege|Quick reference]] and [[https://​perso.limsi.fr/​pointal/​python:​memento|Cheat sheet]]
  
 ===== Some good coding tips ===== ===== Some good coding tips =====
other/python/jyp_steps.txt · Last modified: 2024/03/07 10:15 by jypeter