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--- other:python:misc_by_jyp [2021/08/18 16:04] – Added pprint section jypeter
+++ other:python:misc_by_jyp [2021/09/17 15:41] – [Printing a readable version of long lists or dictionaries] Replaced ordered dict with a regular dict jypeter
@@ Line 50: / Line 50: @@
     * [[https://docs.python.org/3/library/pathlib.html#correspondence-to-tools-in-the-os-module|Matching pathlib, and os or os.path functions]]
   * [[https://docs.python.org/3/library/shutil.html|High-level file operations]]
+=== Example: getting the full path of the Python used ===
+Note: the actual python may be different from the default python!
+<code>$ which python
+/usr/bin/python
+$ /modfs/modtools/miniconda3//envs/analyse_3.6_test/bin/python
+>>> import sys, shutil
+>>> shutil.which('python')
+'/usr/bin/python'
+>>> sys.executable
+'/modfs/modtools/miniconda3//envs/analyse_3.6_test/bin/python'</code>
+=== Example: getting the full path of a script ===
+<code>>>> import os
+>>> os.getcwd()
+'/home/jypmce/PMIP4'
+>>> os.path.exists('./argv_test.py')
+True
+>>> os.path.abspath('./argv_test.py')
+'/home/jypmce/PMIP4/argv_test.py'
+>>> os.path.exists('/home/jypmce/PMIP4/argv_test.py')
+True
+</code>
 === Example: getting the size(s) of all the files in a directory ===
@@ Line 72: / Line 102: @@
 >>> sum(files_sizes)
 </code>
+==== Generating file names ====
+=== Name depending on the current date/time ===
+<code>>>> import time
+>>> plot_version = time.strftime('%Y%m%d_%H%M')
+>>> f_name = 'test_%s.nc' % (plot_version,)
+>>> f_name
+'test_20210827_1334.nc'
+</code>
+=== Temporary file ===
+<code>>>> import tempfile, os
+>>> f_tmp = tempfile.NamedTemporaryFile(mode='w', suffix='.nc', delete=False)
+>>> f_tmp
+<tempfile._TemporaryFileWrapper object at 0x2b5614743820>
+>>> f_tmp.name
+'/tmp/tmpi6uk9hre.nc'
+>>> f_tmp.close()
+>>> os.remove(f_tmp.name)</code>
 ==== Using command-line arguments ====
@@ Line 110: / Line 162: @@
 ==== Using ordered dictionaries ====
-Check the [[https://realpython.com/python-ordereddict/|OrderedDict vs dict in Python: The Right Tool for the Job]] tutorial
+**Dictionary order is guaranteed to be insertion order**! Note that the [[https://docs.python.org/3/library/stdtypes.html#dict|usual Python dictionary]] also guarantees the order since version **3.6**
+Check the [[https://docs.python.org/3/library/collections.html#collections.OrderedDict|OrderedDict class]] (''from collections import OrderedDict'') and the [[https://realpython.com/python-ordereddict/|OrderedDict vs dict in Python: The Right Tool for the Job]] tutorial
 ==== Printing a readable version of long lists or dictionaries ====
@@ Line 116: / Line 170: @@
 The [[https://docs.python.org/3/library/pprint.html|pprint]] module can be used for //pretty printing// objects (lists, dictionaries, ...). It will wrap long lines in a meaningful way
-<code>>>> from collections import OrderedDict
+<code>>>> import pprint
->>> test_dic = OrderedDict([('AWI-ESM-1-1-LR_AWI', {'r1i1p1f1': {'grid': 'gn'}}), ('CESM2_NCAR', {'r1i1p1f1': {'grid': 'gn'}}), ('IPSL-CM6A-LR_IPSL', {'r1i1p1f1': {'grid': 'gr'}, 'r1i1p1f2': {'grid': 'gr'}, 'r1i1p1f3': {'grid': 'gr'}, 'r1i1p1f4': {'grid': 'gr'}})])
+>>> test_dic = {'AWI-ESM-1-1-LR_AWI':{'r1i1p1f1': {'grid': 'gn'}}, 'CESM2_NCAR':{'r1i1p1f1': {'grid': 'gn'}}, 'IPSL-CM6A-LR_IPSL':{'r1i1p1f1': {'grid': 'gr'}, 'r1i1p1f2': {'grid': 'gr'}, 'r1i1p1f3': {'grid': 'gr'}, 'r1i1p1f4': {'grid': 'gr'}}}
 >>> print(test_dic)
-OrderedDict([('AWI-ESM-1-1-LR_AWI', {'r1i1p1f1': {'grid': 'gn'}}), ('CESM2_NCAR', {'r1i1p1f1': {'grid': 'gn'}}), ('IPSL-CM6A-LR_IPSL', {'r1i1p1f1': {'grid': 'gr'}, 'r1i1p1f2': {'grid': 'gr'}, 'r1i1p1f3': {'grid': 'gr'}, 'r1i1p1f4': {'grid': 'gr'}})])
+{'AWI-ESM-1-1-LR_AWI': {'r1i1p1f1': {'grid': 'gn'}}, 'CESM2_NCAR': {'r1i1p1f1': {'grid': 'gn'}}, 'IPSL-CM6A-LR_IPSL': {'r1i1p1f1': {'grid': 'gr'}, 'r1i1p1f2': {'grid': 'gr'}, 'r1i1p1f3': {'grid': 'gr'}, 'r1i1p1f4': {'grid': 'gr'}}}
 >>> pprint.pprint(test_dic)
-OrderedDict([('AWI-ESM-1-1-LR_AWI', {'r1i1p1f1': {'grid': 'gn'}}),
+{'AWI-ESM-1-1-LR_AWI': {'r1i1p1f1': {'grid': 'gn'}},
-             ('CESM2_NCAR', {'r1i1p1f1': {'grid': 'gn'}}),
+ 'CESM2_NCAR': {'r1i1p1f1': {'grid': 'gn'}},
-             ('IPSL-CM6A-LR_IPSL',
+ 'IPSL-CM6A-LR_IPSL': {'r1i1p1f1': {'grid': 'gr'},
-              {'r1i1p1f1': {'grid': 'gr'},
+                       'r1i1p1f2': {'grid': 'gr'},
-               'r1i1p1f2': {'grid': 'gr'},
+                       'r1i1p1f3': {'grid': 'gr'},
-               'r1i1p1f3': {'grid': 'gr'},
+                       'r1i1p1f4': {'grid': 'gr'}}}
-               'r1i1p1f4': {'grid': 'gr'}})])
 </code>