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software:python [2020/12/27 04:01] – [Plotly] superwizardsoftware:python [2024/08/03 02:18] (current) – [Python install] superwizard
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 ------------------------------------------------------------------------------------------------------------------------------------------------\\ ------------------------------------------------------------------------------------------------------------------------------------------------\\
 +
 +====== Python install ======
 +
 +<WRAP center round box >
 +2024-08-02
 +
 +    python -m pip install pandas
 +
 +But when you use python -m pip with python being the specific interpreter you want to use, all of the above ambiguity is gone. If I say python3.8 -m pip then I know pip will be using and installing for my Python 3.8 interpreter (same goes for if I had said python3.7).
 +And if you're on Windows there is an added benefit to using python -m pip as it lets pip update itself. Basically because pip.exe is considered running when you do pip install --upgrade pip, Windows won't let you overwrite pip.exe. But if you do python -m pip install --upgrade pip you avoid that issue as it's python.exe that's running, not pip.exe.
 +
 +From <https://snarky.ca/why-you-should-use-python-m-pip/> 
 +
 +
 +</WRAP>
 +
 +====== Wireshark tcpdump to neo4j plot ======
 +
  
 <WRAP center round box > <WRAP center round box >
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 From <https://plot.ly/python/axes/>  From <https://plot.ly/python/axes/> 
  
 +</WRAP>
  
 +====== Regular Expression ======
 +
 +
 +<WRAP center round box >
  
 2019-05-29 2019-05-29
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 From <https://www.regular-expressions.info/regexmagic.html>  From <https://www.regular-expressions.info/regexmagic.html> 
- 
- 
- 
- 
  
 </WRAP> </WRAP>
  
-====== Plotly ======+====== Split the string at the last occurrence of sep ======
  
 <WRAP center round box > <WRAP center round box >
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 From <https://docs.python.org/3/library/stdtypes.html#string-methods>  From <https://docs.python.org/3/library/stdtypes.html#string-methods> 
 +</WRAP>
  
 +====== The built-in os module has a number of useful functions ======
 +
 +<WRAP center round box >
 The built-in os module has a number of useful functions that can be used to list directory contents and filter the results. To get a list of all the files and folders in a particular directory in the filesystem, use os.listdir() in legacy versions of Python or os.scandir() in Python 3.x. os.scandir() is the preferred method to use if you also want to get file and directory properties such as file size and modification date. The built-in os module has a number of useful functions that can be used to list directory contents and filter the results. To get a list of all the files and folders in a particular directory in the filesystem, use os.listdir() in legacy versions of Python or os.scandir() in Python 3.x. os.scandir() is the preferred method to use if you also want to get file and directory properties such as file size and modification date.
  
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 +</WRAP>
 +
 +====== Splitting, Concatenating, and Joining Strings in Python ======
 +
 +<WRAP center round box >
 2019-05-20 2019-05-20
  
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 +</WRAP>
 +
 +====== Regex Testor ======
 +
 +<WRAP center round box >
 Regex Testor Regex Testor
  
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 https://regex101.com/ https://regex101.com/
  
 +</WRAP>
 +
 +====== processdokuwikifile ======
 +
 +<WRAP center round box >
 2019-05-15 2019-05-15
  
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 From <https://www.vipinajayakumar.com/parsing-text-with-python/>  From <https://www.vipinajayakumar.com/parsing-text-with-python/> 
 +</WRAP>
  
 +====== PASS BY OBJECT REFERENCE (Case in python): ======
  
 +<WRAP center round box >
  
 2019-04-08 2019-04-08
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 From <https://stackoverflow.com/questions/13299427/python-functions-call-by-reference>  From <https://stackoverflow.com/questions/13299427/python-functions-call-by-reference> 
 +</WRAP>
  
  
  
 +====== Plotly ======
 +
 +<WRAP center round box >
 2019-03-31 2019-03-31
  
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 +</WRAP>
 +
 +====== Python write to CSV ======
 +
 +
 +<WRAP center round box >
  
 2019-03-29 2019-03-29
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 From <https://stackoverflow.com/questions/2084069/create-a-csv-file-with-values-from-a-python-list>  From <https://stackoverflow.com/questions/2084069/create-a-csv-file-with-values-from-a-python-list> 
 +</WRAP>
  
 +====== CSV in Python adding an extra carriage return, on Windows ======
 +
 +<WRAP center round box >
  
 CSV in Python adding an extra carriage return, on Windows CSV in Python adding an extra carriage return, on Windows
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 From <https://stackoverflow.com/questions/3191528/csv-in-python-adding-an-extra-carriage-return-on-windows>  From <https://stackoverflow.com/questions/3191528/csv-in-python-adding-an-extra-carriage-return-on-windows> 
  
 +</WRAP>
 +
 +====== Examples of simple type checking in Python: ======
 +
 +
 +<WRAP center round box >
 2019-02-17 2019-02-17
  
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 From <https://stackoverflow.com/questions/402504/how-to-determine-a-python-variables-type>  From <https://stackoverflow.com/questions/402504/how-to-determine-a-python-variables-type> 
  
 +</WRAP>
 +
 +====== isinstance() ======
 +
 +<WRAP center round box >
 With one argument, return the type of an object. The return value is a type object. The isinstance() built-in function is recommended for testing With one argument, return the type of an object. The return value is a type object. The isinstance() built-in function is recommended for testing
  
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 From <https://www.geeksforgeeks.org/type-isinstance-python/>  From <https://www.geeksforgeeks.org/type-isinstance-python/> 
- 
- 
- 
  
 </WRAP> </WRAP>
  
-<WRAP center round box 60%>+====== graph-cli ====== 
 + 
 +<WRAP center round box >
 2019-01-05 2019-01-05
  
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 +</WRAP>
 +
 +====== copy2 ======
 +
 +<WRAP center round box >
  
 2018-12-25 2018-12-25
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 From <https://stackabuse.com/how-to-copy-a-file-in-python/>  From <https://stackabuse.com/how-to-copy-a-file-in-python/> 
  
 +</WRAP>
 +
 +====== Start of String Only: \A ======
 +
 +<WRAP center round box >
  
 Start of String Only: \A Start of String Only: \A
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 From <https://docs.microsoft.com/en-us/dotnet/standard/base-types/anchors-in-regular-expressions>  From <https://docs.microsoft.com/en-us/dotnet/standard/base-types/anchors-in-regular-expressions> 
 +
 +</WRAP>
 +
 +====== Decimals interact well with much of the rest of Python ======
 +
 +<WRAP center round box >
  
 decimal — Decimal fixed point and floating point arithmetic decimal — Decimal fixed point and floating point arithmetic
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 From <https://docs.python.org/3/library/decimal.html>  From <https://docs.python.org/3/library/decimal.html> 
 +
 +</WRAP>
 +
 +====== splitting a number into the integer and decimal parts ======
 +
 +<WRAP center round box >
 +
  
 splitting a number into the integer and decimal parts splitting a number into the integer and decimal parts
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 From <https://www.w3schools.com/python/python_datetime.asp>  From <https://www.w3schools.com/python/python_datetime.asp> 
  
 +</WRAP>
 +
 +====== Module datetime provides ======
 +
 +<WRAP center round box >
  
 Module datetime provides classes for manipulating date and time in more object oriented way. One of them is datetime.datetime.now which return number of seconds since the epoch. Module datetime provides classes for manipulating date and time in more object oriented way. One of them is datetime.datetime.now which return number of seconds since the epoch.
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 +</WRAP>
 +
 +====== Example 2: Right justify string and fill the remaining spaces ======
 +
 +<WRAP center round box >
 Example 2: Right justify string and fill the remaining spaces Example 2: Right justify string and fill the remaining spaces
  
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 From <https://www.programiz.com/python-programming/methods/string/rjust>  From <https://www.programiz.com/python-programming/methods/string/rjust> 
  
 +</WRAP>
  
 +====== Practical Business Python ======
  
 +<WRAP center round box >
 2018-12-24 2018-12-24
  
 Practical Business Python Practical Business Python
- 
  
 pbpython/extras/Pathlib-Cheatsheet.pdf pbpython/extras/Pathlib-Cheatsheet.pdf
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 +</WRAP>
  
 +====== The divmod() returns ======
  
 +<WRAP center round box >
  
  
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 From <https://www.programiz.com/python-programming/methods/built-in/divmod>  From <https://www.programiz.com/python-programming/methods/built-in/divmod> 
  
 +</WRAP>
 +
 +====== numpy ======
 +
 +<WRAP center round box >
 2018-11-18 2018-11-18
  
 +<code>
 pip install numpy pip install numpy
 +</code>
  
 From <https://pypi.org/project/numpy/>  From <https://pypi.org/project/numpy/> 
  
 +<code>
 pip3.6 install numpy pip3.6 install numpy
 pip3.6 install scipy pip3.6 install scipy
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 Install opencv-python instead of cv2. Install opencv-python instead of cv2.
 pip install opencv-python pip install opencv-python
 +</code>
  
 From <https://github.com/jazzsaxmafia/video_to_sequence/issues/3>  From <https://github.com/jazzsaxmafia/video_to_sequence/issues/3> 
  
 +</WRAP>
 +
 +====== compare the use of lambda ======
 +
 +<WRAP center round box >
  
  
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 From <https://stackoverflow.com/questions/8966538/syntax-behind-sortedkey-lambda>  From <https://stackoverflow.com/questions/8966538/syntax-behind-sortedkey-lambda> 
 +</WRAP>
 +
 +====== Key Functions ======
 +
 +<WRAP center round box >
  
 Key Functions Key Functions
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 This image was created with the following code. This image was created with the following code.
  
 +<code>
 1 import operator                                                   1 import operator                                                  
 2 import pylab 2 import pylab
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 26 pylab.grid() 26 pylab.grid()
 27 pylab.title("Performance sorted dictionary by values") 27 pylab.title("Performance sorted dictionary by values")
 +</code>
  
 From <http://thomas-cokelaer.info/blog/2017/12/how-to-sort-a-dictionary-by-values-in-python/>  From <http://thomas-cokelaer.info/blog/2017/12/how-to-sort-a-dictionary-by-values-in-python/> 
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 As already said, iteritems() will be a problem, but you mention a syntax error, which comes from the lambda declaration with parenthesis: As already said, iteritems() will be a problem, but you mention a syntax error, which comes from the lambda declaration with parenthesis:
 Change: Change:
 +<code>
 key=lambda(k, v): sort_order.index(k) key=lambda(k, v): sort_order.index(k)
 +</code>
 To: To:
 +<code>
 key=lambda k, v: sort_order.index(k) key=lambda k, v: sort_order.index(k)
 +</code>
  
 From <https://stackoverflow.com/questions/47749438/lambda-sorting-in-python-3>  From <https://stackoverflow.com/questions/47749438/lambda-sorting-in-python-3> 
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 </WRAP> </WRAP>
  
-<WRAP center round box 60%>+====== What problem does pandas solve? ====== 
 + 
 +<WRAP center round box >
  
 2018-11-15 2018-11-15
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 NumPy NumPy
 +<code>
 NumPy is the fundamental package for scientific computing with Python. It contains among other things: NumPy is the fundamental package for scientific computing with Python. It contains among other things:
 • a powerful N-dimensional array object • a powerful N-dimensional array object
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 • tools for integrating C/C++ and Fortran code • tools for integrating C/C++ and Fortran code
 • useful linear algebra, Fourier transform, and random number capabilities • useful linear algebra, Fourier transform, and random number capabilities
 +</code>
  
 From <http://www.numpy.org/>  From <http://www.numpy.org/> 
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 From <https://machinelearningmastery.com/broadcasting-with-numpy-arrays/>  From <https://machinelearningmastery.com/broadcasting-with-numpy-arrays/> 
 +
 +</WRAP>
 +
 +====== scikit-learn ======
 +
 +<WRAP center round box >
  
 scikit-learn scikit-learn
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 From <http://pybrain.org/>  From <http://pybrain.org/> 
  
 +</WRAP>
  
 +====== python read fails on special characters ======
  
 +<WRAP center round box >
  
 2018-11-06 2018-11-06
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 From <https://stackoverflow.com/questions/47635759/how-to-read-a-text-file-with-special-characters-in-python>  From <https://stackoverflow.com/questions/47635759/how-to-read-a-text-file-with-special-characters-in-python> 
 +</WRAP>
  
 +====== idle args ======
  
 +
 +<WRAP center round box >
  
 2018-10-31 2018-10-31
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 Pending application of a patch, the following will work to only add args to sys.argv when running from an Idle editor. Pending application of a patch, the following will work to only add args to sys.argv when running from an Idle editor.
 +<code>
 import sys import sys
 # ... # ...
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 except: except:
     sys.argv = [sys.argv[0], 'argument1', 'argument2', 'argument2']     sys.argv = [sys.argv[0], 'argument1', 'argument2', 'argument2']
 +</code>
  
 From <https://stackoverflow.com/questions/2148994/when-running-a-python-script-in-idle-is-there-a-way-to-pass-in-command-line-arg>  From <https://stackoverflow.com/questions/2148994/when-running-a-python-script-in-idle-is-there-a-way-to-pass-in-command-line-arg> 
  
 +</WRAP>
  
 +====== Auto detect IDLE and prompt for command-line argument values ======
 +
 +
 +<WRAP center round box >
  
 2018-10-31 2018-10-31
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 Auto detect IDLE and prompt for command-line argument values Auto detect IDLE and prompt for command-line argument values
  
-#! /usr/bin/env python3+<code> 
 +c#! /usr/bin/env python3
 import sys import sys
 def ok(x=None): def ok(x=None):
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       root.bind("<Escape>", lambda x: root.destroy())       root.bind("<Escape>", lambda x: root.destroy())
 e.focus() e.focus()
 +</code>
  
 From <https://stackoverflow.com/questions/2148994/when-running-a-python-script-in-idle-is-there-a-way-to-pass-in-command-line-arg/44687632#44687632>  From <https://stackoverflow.com/questions/2148994/when-running-a-python-script-in-idle-is-there-a-way-to-pass-in-command-line-arg/44687632#44687632> 
  
 +</WRAP>
 +
 +====== print the files deleted ======
 +
 +<WRAP center round box >
  
  
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         pass         pass
 </code> </code>
 +
 +</WRAP>
 +
 +====== delete directories ======
 +
 +<WRAP center round box >
 Here's an alternative Python script that is case sensitive and will also delete directories included in the list Here's an alternative Python script that is case sensitive and will also delete directories included in the list
 <code> <code>
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 +</WRAP>
 +
 +====== checkpoints ======
 +
 +<WRAP center round box >
  
 2018-10-06 2018-10-06
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 From <https://www.programcreek.com/python/example/92/glob.glob>  From <https://www.programcreek.com/python/example/92/glob.glob> 
 +</WRAP>
  
 +====== argparse ======
  
 +<WRAP center round box >
  
 2018-10-06 2018-10-06
software/python.1609041705.txt.gz · Last modified: by superwizard