GJainLIB

Overview:

gjainLIB: A custom python module containing:

• Optimal python functions commonly used in my python scripts
• Mostly collected from stackoverflow and modified to improve performance

Table of contents

1. get_file_info
2. create_dir
3. get_fileslist_in_dir
4. print_initial_arguments
5. useful_lines
6. get_unique_list
7. get_line_counts
8. get_line_counts_pygen
9. get_temp_file
10. Log

Description

The module contains functions and classes. They are:

1. get_file_info():

   • Get path, basename, ext, path+basename and basename+ext of a file
   • Input parameters:
     • file_name_with_path: str
       Filename with or without absolute/relative path
   • Returns:
     • input_file_path
     • input_file_basename
     • input_file_extension
     • path_filename
     • input_file_name
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2. create_dir():

   • Creates a directory if not exists
   • Input parameters:
     • dirname: str
       Folder/directory name with or without absolute/relative path
   • Returns:
     • Relevant status messages on error
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3. get_fileslist_in_dir():

   • Get the list of files inside a directory
   • If extension is passed then return files for that extension
   • Input parameters:
     • dirname: str
       Folder/directory name with or without absolute/relative path
     • exts: str, list, optional List of extensions to filter out for filetype
   • Returns:
     • specific files if extensions are passed
     • all files if extensions are not passed
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4. print_initial_arguments():

   • Print the script name and all the initial arguments entered in the script
   • Input parameters:
     • parser: object
       Instance of ArgumentParser object
   • Returns:
     • None
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5. useful_lines():

   • Skips all the comments (right now #) from the file and returns the generator object of lines without comments
   • It remembers the state where it left. So it will start after the last executed line
   • Input parameters:
     • fh: file
       File handle of the file
   • Returns:
     • generator for the last read line in the file
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6. get_unique_list():

   • Get unique element in a list with the order of elements preserved
   • Input parameters:
     • seq: list
       File handle of the file
     • idfun: function, optional
       A function that can transform the list values
   • Returns:
     • generator for the unique and ordered preserved list
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7. get_line_counts():

   • Get the number of lines in a file efficiently
   • Implemented with generators expressions in-line using itertools
   • Input parameters:
     • filename: str
       Filename with or without absolute/relative path
   • Returns:
     • Total number of lines in the file
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8. get_line_counts_pygen():

   • Get the number of lines in a file efficiently
   • Implemented with generators expressions without using itertools
   • Works for files as big as 100+ Gb
   • Input parameters:
     • filename: str
       Filename with or without absolute/relative path
   • Returns:
     • Total number of lines in the file
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9. get_temp_file():

   • Create a temporary file
   • The file will be deleted at program exit
   • Input parameters:
     • suffix: str, optional
       Filename with or without absolute/relative path
     • prefix: str, optional Temporary file extension
     • dir: str, optional Folder/directory name with or without absolute/relative path where the temporary file will be created
   • Returns:
     • Filename with absolute path
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10. Log():

    • A class for saving the STDOUT output in a log file
    • Input parameters:
      • logf: file
        File handle of the log file
    • Returns:
      • Write STDOUT in the log file
      • Return None
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