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python patterns 1
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10
howtos_as_py_files/README.md
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10
howtos_as_py_files/README.md
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Sebastian Raschka
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last updated: 09/26/2014
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# A collection of useful Python patterns
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new_msg("Hello, World")
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# prints: "My message: Hello, World"
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# print(dir(create_message.__closure__))
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# Python 3.x
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# sr 11/04/2013
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# closures
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#
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def create_message(msg_txt):
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def _priv_msg(message): # private, no access from outside
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print("{}: {}".format(msg_txt, message))
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return _priv_msg # returns a function
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new_msg = create_message("My message")
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# note, new_msg is a function
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new_msg("Hello, World")
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# prints: "My message: Hello, World"
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# print(dir(create_message.__closure__))
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# Getting command line arguments via sys.arg
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# sr 11/30/2013
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import sys
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def error(msg):
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"""Prints error message, sends it to stderr, and quites the program."""
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sys.exit(msg)
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args = sys.argv[1:] # sys.argv[0] is the name of the python script itself
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try:
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arg1 = int(args[0])
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arg2 = args[1]
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arg3 = args[2]
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print("Everything okay!")
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except ValueError:
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error("First argument must be integer type!")
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except IndexError:
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error("Requires 3 arguments!")
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# sr 10/29/13
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# Calculates elapsed CPU time in seconds as float.
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import time
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start_time = time.clock()
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i = 0
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while i < 10000000:
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i += 1
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elapsed_time = time.clock() - start_time
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print "Time elapsed: {} seconds".format(elapsed_time)
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# prints "Time elapsed: 1.06 seconds"
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# on 4 x 2.80 Ghz Intel Xeon, 6 Gb RAM
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@ -1,13 +0,0 @@
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# Sebastian Raschka, 03/2014
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# Date and Time in Python
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import time
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# print time HOURS:MINUTES:SECONDS
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# e.g., '10:50:58'
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print(time.strftime("%H:%M:%S"))
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# print current date DAY:MONTH:YEAR
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# e.g., '06/03/2014'
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print(time.strftime("%d/%m/%Y"))
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# Sebastian Raschka, 2014
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#
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# Print lines that are different between 2 files. Insensitive
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# to the order of the file contents.
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id_set1 = set()
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id_set2 = set()
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with open('id_file1.txt', 'r') as id_file:
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for line in id_file:
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id_set1.add(line.strip())
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with open('id_file2.txt', 'r') as id_file:
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for line in id_file:
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id_set2.add(line.strip())
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diffs = id_set2.difference(id_set1)
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for d in diffs:
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print(d)
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print("Total differences:",len(diffs))
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# doctest example
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# Sebastian Raschka 11/19/2013
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def subtract(a, b):
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"""
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Subtracts second from first number and returns result.
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>>> subtract(10, 5)
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5
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>>> subtract(11, 0.7)
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10.3
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"""
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return a-b
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def hello_world():
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"""
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Returns 'Hello, World'
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>>> hello_world()
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"Hello, World"
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>>> hello_world()
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'Hello, World'
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"""
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return "Hello, World"
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if __name__ == "__main__": # is 'false' if imported
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import doctest
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doctest.testmod()
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""" RESULTS
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sebastian ~/Desktop> python3 doctest_example.py
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**********************************************************************
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File "doctest_example.py", line 17, in __main__.hello_world
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Failed example:
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hello_world()
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Expected:
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"Hello, World"
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Got:
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'Hello, World'
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**********************************************************************
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1 items had failures:
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1 of 2 in __main__.hello_world
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***Test Failed*** 1 failures.
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sebastian ~/Desktop>
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"""
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# File system operations using Python
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# sr 11/30/2013
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import os
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import shutil
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import glob
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# working directory
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c_dir = os.getcwd() # show current working directory
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os.listdir(c_dir) # shows all files in the working directory
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os.chdir('~/Data') # change working directory
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# get all files in a directory
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glob.glob('/Users/sebastian/Desktop/*')
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# e.g., ['/Users/sebastian/Desktop/untitled folder', '/Users/sebastian/Desktop/Untitled.txt']
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# walk
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tree = os.walk(c_dir)
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# moves through sub directories and creates a 'generator' object of tuples
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# ('dir', [file1, file2, ...] [subdirectory1, subdirectory2, ...]),
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# (...), ...
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#check files: returns either True or False
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os.exists('../rel_path')
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os.exists('/home/abs_path')
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os.isfile('./file.txt')
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os.isdir('./subdir')
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# file permission (True or False
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os.access('./some_file', os.F_OK) # File exists? Python 2.7
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os.access('./some_file', os.R_OK) # Ok to read? Python 2.7
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os.access('./some_file', os.W_OK) # Ok to write? Python 2.7
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os.access('./some_file', os.X_OK) # Ok to execute? Python 2.7
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os.access('./some_file', os.X_OK | os.W_OK) # Ok to execute or write? Python 2.7
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# join (creates operating system dependent paths)
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os.path.join('a', 'b', 'c')
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# 'a/b/c' on Unix/Linux
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# 'a\\b\\c' on Windows
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os.path.normpath('a/b/c') # converts file separators
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# os.path: direcory and file names
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os.path.samefile('./some_file', '/home/some_file') # True if those are the same
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os.path.dirname('./some_file') # returns '.' (everythin but last component)
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os.path.basename('./some_file') # returns 'some_file' (only last component
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os.path.split('./some_file') # returns (dirname, basename) or ('.', 'some_file)
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os.path.splitext('./some_file.txt') # returns ('./some_file', '.txt')
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os.path.splitdrive('./some_file.txt') # returns ('', './some_file.txt')
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os.path.isabs('./some_file.txt') # returns False (not an absolute path)
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os.path.abspath('./some_file.txt')
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# create and delete files and directories
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os.mkdir('./test') # create a new direcotory
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os.rmdir('./test') # removes an empty direcotory
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os.removedirs('./test') # removes nested empty directories
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os.remove('file.txt') # removes an individual file
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shutil.rmtree('./test') # removes directory (empty or not empty)
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os.rename('./dir_before', './renamed') # renames directory if destination doesn't exist
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shutil.move('./dir_before', './renamed') # renames directory always
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shutil.copytree('./orig', './copy') # copies a directory recursively
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shutil.copyfile('file', 'copy') # copies a file
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# Python 2.7
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# prompt user for file of specific type(s).
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# 11/01/13 sebastian raschka
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import os.path
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def get_filename(file_type):
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'''repeatedly prompts user for a file of specific type.
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arguments:
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file_type: list with accepted file types as strings.
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returns:
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(string): absolute path to the specified input file.
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'''
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while True:
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print "\n\nplease enter a file name, \nor type --help to get"\
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" a list of the accepted file formats"
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file_name = raw_input(": ")
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if file_name == "--help":
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print "\naccepted file format(s): ",
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for f in file_type:
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print f,
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continue
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if not os.path.isfile(file_name):
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print "\n\nsorry, this file doesn't exist. please try again.\n"
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continue
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if not (file_name.split(".")[-1] in file_type):
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print "\nplease provide a file in correct format."
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continue
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break
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return os.path.abspath(file_name)
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#get_filename(["txt", "doc"])
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# ===========================
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# EXAMPLE
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# ===========================
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'''
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[bash]~/Desktop >python get_filename.py
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please enter a file name,
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or type --help to get a list of the accepted file formats
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: --help
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accepted file format(s): txt doc
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please enter a file name,
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or type --help to get a list of the accepted file formats
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: test.tx
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sorry, this file doesn't exist. please try again.
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please enter a file name,
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or type --help to get a list of the accepted file formats
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: test.txt
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[bash]~/Desktop >
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'''
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# Sebastian Raschka, 03/2014
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# Getting the positions of min and max values in a list
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import operator
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values = [1, 2, 3, 4, 5]
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min_index, min_value = min(enumerate(values), key=operator.itemgetter(1))
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max_index, max_value = max(enumerate(values), key=operator.itemgetter(1))
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print('min_index:', min_index, 'min_value:', min_value)
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print('max_index:', max_index, 'max_value:', max_value)
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3
howtos_as_py_files/id_file1.txt
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3
howtos_as_py_files/id_file1.txt
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1234
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2342
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2341
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3
howtos_as_py_files/id_file2.txt
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3
howtos_as_py_files/id_file2.txt
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5234
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3344
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2341
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# Sebastian Raschka 08/2014
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# Lambda functions are just a short-hand way or writing
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# short function definitions
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def square_root1(x):
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return x**0.5
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square_root2 = lambda x: x**0.5
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assert(square_root1(9) == square_root2(9))
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# Generating a bitstring from a Python list or numpy array
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# where all postive values -> 1
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# all negative values -> 0
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def make_bitstring(ary)
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return np.where(ary > 0, 1, 0)
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def faster_bitstring(ary)
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return np.where(ary > 0).astype('i1')
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### Example:
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ary1 = np.array([1, 2, 0.3, -1, -2])
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make_bitstring(ary1)
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# returns array([1, 1, 1, 0, 0])
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BIN
howtos_as_py_files/my_file.pkl
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BIN
howtos_as_py_files/my_file.pkl
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Binary file not shown.
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from collections import namedtuple
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my_namedtuple = namedtuple('field_name', ['x', 'y', 'z', 'bla', 'blub'])
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p = my_namedtuple(1, 2, 3, 4, 5)
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print(p.x, p.y, p.z)
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# Sebastian Raschka, 03/2014
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def normalize_val(x, data_list):
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"""
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Normalizes a value to a data list returning a float
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between 0.0 and 1.0.
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Returns the original object if value is not a integer or float.
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"""
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if isinstance(x, float) or isinstance(x, int):
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numerator = x - min(data_list)
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denominator = max(data_list) - min(data_list)
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return numerator/denominator
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else:
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return x
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# numpy matrix operations
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# sr 12/01/2013
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import numpy
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ary1 = numpy.array([1,2,3,4,5]) # must be same type
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ary2 = numpy.zeros((3,4)) # 3x4 matrix consisiting of 0s
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ary3 = numpy.ones((3,4)) # 3x4 matrix consisiting of 1s
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ary4 = numpy.identity(3) # 3x3 identity matrix
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ary5 = ary1.copy() # make a copy of ary1
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item1 = ary3[0, 0] # item in row1, column1
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ary2.shape # tuple of dimensions. Here: (3,4)
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ary2.size # number of elements. Here: 12
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ary2_t = ary2.transpose() # transposes matrix
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ary2.ravel() # makes an array linear (1-dimensional)
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# by concatenating rows
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ary2.reshape(2,6) # reshapes array (must have same dimensions)
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ary3[0:2, 0:3] # submatrix of first 2 rows and first 3 columns
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ary3 = ary3[[2,0,1]] # re-arrange rows
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# element-wise operations
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ary1 + ary1
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ary1 * ary1
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numpy.dot(ary1, ary1) # matrix/vector (dot) product
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numpy.sum(ary1) # sums up all elements in the array
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numpy.mean(ary1) # average of all elements in the array
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# sr 11/19/2013
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# common file operations in os and shutil modules
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import shutil
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import os
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# Getting files of particular type from directory
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files = [f for f in os.listdir(s_pdb_dir) if f.endswith(".txt")]
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# Copy and move
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shutil.copyfile("/path/to/file", "/path/to/new/file")
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shutil.copy("/path/to/file", "/path/to/directory")
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shutil.move("/path/to/file","/path/to/directory")
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# Check if file or directory exists
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os.path.exists("file or directory")
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os.path.isfile("file")
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os.path.isdir("directory")
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# Working directory and absolute path to files
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os.getcwd()
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os.path.abspath("file")
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1486
howtos_as_py_files/patterns.ipynb
Normal file
1486
howtos_as_py_files/patterns.ipynb
Normal file
File diff suppressed because it is too large
Load Diff
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# sr 10/29/13
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# The pickle module converts Python objects into byte streams
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# to save them as a file on your drive for re-use.
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#
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# module documentation http://docs.python.org/2/library/pickle.html
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import pickle
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#### Generate some object
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my_dict = dict()
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for i in range(1,1000):
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my_dict[i] = "some text"
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#### Save object to file
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pickle_out = open('my_file.pkl', 'wb')
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pickle.dump(my_dict, pickle_out)
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pickle_out.close()
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#### Load object from file
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my_object_file = open('my_file.pkl', 'rb')
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my_dict = pickle.load(my_object_file)
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my_object_file.close()
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# Sebastian Raschka 04/10/2014
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import sys
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def give_letter(word):
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for letter in word:
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yield letter
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if sys.version_info[0] == 3:
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print('executed in Python 3.x')
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test = give_letter('Hello')
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print(next(test))
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print('in for-loop:')
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for l in test:
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print(l)
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# if Python 2.x
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if sys.version_info[0] == 2:
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print('executed in Python 2.x')
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test = give_letter('Hello')
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print(test.next())
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print('in for-loop:')
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for l in test:
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print(l)
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@ -1,44 +0,0 @@
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# Different methods to read from text files
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# sr 11/18/2013
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# Python 3.x
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# Note: rb opens file in binary mode to avoid issues with Windows systems
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# where '\r\n' is used instead of '\n' as newline character(s).
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||||
|
||||
# A) Reading in Byte chunks
|
||||
reader_a = open("file.txt", "rb")
|
||||
chunks = []
|
||||
data = reader_a.read(64) # reads first 64 bytes
|
||||
while data != "":
|
||||
chunks.append(data)
|
||||
data = reader_a.read(64)
|
||||
if data:
|
||||
chunks.append(data)
|
||||
print (len(chunks))
|
||||
reader_a.close()
|
||||
|
||||
|
||||
# B) Reading whole file at once into a list of lines
|
||||
with open("file.txt", "rb") as reader_b: # recommended syntax, auto closes
|
||||
data = reader_b.readlines() # data is assigned a list of lines
|
||||
print (len(data))
|
||||
|
||||
|
||||
# C) Reading whole file at once into a string
|
||||
with open("file.txt", "rb") as reader_c:
|
||||
data = reader_c.read() # data is assigned a list of lines
|
||||
print (len(data))
|
||||
|
||||
|
||||
# D) Reading line by line into a list
|
||||
data = []
|
||||
with open("file.txt", "rb") as reader_d:
|
||||
for line in reader_d:
|
||||
data.append(line)
|
||||
print (len(data))
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
|
@ -1,101 +0,0 @@
|
|||
# Examples for using Python's Regular expression module "re"
|
||||
# sr 11/30/2013
|
||||
|
||||
import re
|
||||
|
||||
'''OVERVIEW
|
||||
'|' means 'or'
|
||||
'.' matches any single character
|
||||
'()' groups into substrings
|
||||
'''
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
# read in data
|
||||
fileobj = '''abc mno
|
||||
def pqr
|
||||
ghi stu
|
||||
jkl vwx'''
|
||||
|
||||
data = fileobj.strip().split('\n')
|
||||
|
||||
|
||||
# A >> if 's' in line
|
||||
print (50*'-' + '\nA\n' + 50*'-')
|
||||
for line in data:
|
||||
if re.search('abc', line):
|
||||
print(">>", line)
|
||||
else:
|
||||
print(" ", line)
|
||||
|
||||
'''
|
||||
--------------------------------------------------
|
||||
A
|
||||
--------------------------------------------------
|
||||
>> abc mno
|
||||
def pqr
|
||||
ghi stu
|
||||
jkl vwx'''
|
||||
|
||||
|
||||
|
||||
# B >> if 's' in line or 'r' in line
|
||||
print (50*'-' + '\nB\n' + 50*'-')
|
||||
for line in data:
|
||||
if re.search('abc|efg', line):
|
||||
print(">>", line)
|
||||
else:
|
||||
print(" ", line)
|
||||
|
||||
'''
|
||||
--------------------------------------------------
|
||||
B
|
||||
--------------------------------------------------
|
||||
>> abc mno
|
||||
def pqr
|
||||
ghi stu
|
||||
jkl vwx
|
||||
---------------'''
|
||||
|
||||
|
||||
# C >>
|
||||
# use () to remember which object was found and return a match object
|
||||
print (50*'-' + '\nC\n' + 50*'-')
|
||||
for line in data:
|
||||
match = re.search('(abc|efg)', line) # note the parantheses
|
||||
if match:
|
||||
print(match.group(1)) # prints 'abc' if found, else None
|
||||
# match.group(0) is the whole pattern that matched
|
||||
|
||||
'''
|
||||
--------------------------------------------------
|
||||
C
|
||||
--------------------------------------------------
|
||||
abc'''
|
||||
|
||||
|
||||
|
||||
# read in data
|
||||
fileobj = '''2013-01-01
|
||||
2012-02-02
|
||||
ghi stu
|
||||
2012-03-03'''
|
||||
|
||||
data = fileobj.strip().split('\n')
|
||||
|
||||
|
||||
# D >> use '.' to match 'any character'
|
||||
print (50*'-' + '\nD\n' + 50*'-')
|
||||
for line in data:
|
||||
match = re.search('(2012)-(..)-(..)', line) # note the parantheses
|
||||
if match:
|
||||
print(match.group(1), match.group(2), match.group(3))
|
||||
|
||||
'''
|
||||
--------------------------------------------------
|
||||
D
|
||||
--------------------------------------------------
|
||||
2012 02 02
|
||||
2012 03 03'''
|
||||
|
|
@ -1,127 +0,0 @@
|
|||
# Examples for using Python's Regular expression module "re"
|
||||
# sr 11/30/2013
|
||||
|
||||
import re
|
||||
|
||||
'''OVERVIEW
|
||||
'*' matches all characters that follow (0 or more)
|
||||
'+' matches all characters that follow (1 or more)
|
||||
'?' makes the previous character optional
|
||||
'{4}' previous character must match exactly 4 times
|
||||
'{2-4}' previous character must match exactly 2-4 times
|
||||
'[0-9]' matches all characters in the set of numbers 0 to 9
|
||||
'[A-Z]' matches all characters in the set of A to Z
|
||||
'\d' matches all digits, e.g., '4', '9' ...
|
||||
'\D' matches all NON-digit characters
|
||||
'\s' matches all space characters: '', '\t', '\r', '\n'
|
||||
'\S' matches all NON-space characters
|
||||
'\w' matches all non-punctuation characters (i.e., letters and digits)
|
||||
'\W' matches all NON-letter and NON-digit characters
|
||||
'^bla' NOT-matches 'bla'
|
||||
'let$' matches 'let' but not 'letter'
|
||||
'\b' matches transition between non-word characters and word characters
|
||||
|
||||
'''
|
||||
|
||||
data = '''2013-01-01
|
||||
2012-02-02
|
||||
aaaa-02-02
|
||||
aa-02-02
|
||||
-04-04
|
||||
2000 02-02
|
||||
ghi stu
|
||||
2012-03-03'''.strip().split('\n')
|
||||
|
||||
|
||||
# A >> '*' matches all characters that follow (0 or more)
|
||||
print (50*'-' + '\nA\n' + 50*'-')
|
||||
|
||||
for line in data:
|
||||
match = re.search('(.*)-(..)-(..)', line) # note the parantheses
|
||||
if match:
|
||||
print(match.group(1), match.group(2), match.group(3))
|
||||
|
||||
'''
|
||||
--------------------------------------------------
|
||||
A
|
||||
--------------------------------------------------
|
||||
2013 01 01
|
||||
2012 02 02
|
||||
aaaa 02 02
|
||||
aa 02 02
|
||||
04 04
|
||||
2012 03 03
|
||||
'''
|
||||
|
||||
|
||||
# B >> '+' matches all characters that follow (1 or more)
|
||||
print (50*'-' + '\nB\n' + 50*'-')
|
||||
|
||||
for line in data:
|
||||
match = re.search('(.+)-(..)-(..)', line) # note the parantheses
|
||||
if match:
|
||||
print(match.group(1), match.group(2), match.group(3))
|
||||
|
||||
'''
|
||||
--------------------------------------------------
|
||||
B
|
||||
--------------------------------------------------
|
||||
2013 01 01
|
||||
2012 02 02
|
||||
aaaa 02 02
|
||||
aa 02 02
|
||||
2012 03 03
|
||||
'''
|
||||
|
||||
|
||||
# C >> '?' makes the previous character optional
|
||||
print (50*'-' + '\nC\n' + 50*'-')
|
||||
|
||||
for line in data:
|
||||
match = re.search('(.+)-?(..)-(..)', line) # note the parantheses
|
||||
if match:
|
||||
print(match.group(1), match.group(2), match.group(3))
|
||||
|
||||
'''
|
||||
--------------------------------------------------
|
||||
C
|
||||
--------------------------------------------------
|
||||
2013- 01 01
|
||||
2012- 02 02
|
||||
aaaa- 02 02
|
||||
aa- 02 02
|
||||
- 04 04
|
||||
2000 02 02
|
||||
2012- 03 03
|
||||
'''
|
||||
|
||||
# D >> '{4}' previous character must match exactly 4 times
|
||||
print (50*'-' + '\nD\n' + 50*'-')
|
||||
|
||||
for line in data:
|
||||
match = re.search('(a{4})-(..)-(..)', line) # note the parantheses
|
||||
if match:
|
||||
print(match.group(1), match.group(2), match.group(3))
|
||||
|
||||
'''
|
||||
--------------------------------------------------
|
||||
D
|
||||
--------------------------------------------------
|
||||
aaaa 02 02
|
||||
'''
|
||||
|
||||
# E >>'{2-4}' previous character must match exactly 2-4 times
|
||||
print (50*'-' + '\nE\n' + 50*'-')
|
||||
|
||||
for line in data:
|
||||
match = re.search('(a{2,4})-(..)-(..)', line) # note the parantheses
|
||||
if match:
|
||||
print(match.group(1), match.group(2), match.group(3))
|
||||
|
||||
'''
|
||||
--------------------------------------------------
|
||||
E
|
||||
--------------------------------------------------
|
||||
aaaa 02 02
|
||||
aa 02 02
|
||||
'''
|
||||
|
|
@ -1,34 +0,0 @@
|
|||
# Sebastian Raschka 09/02/2014
|
||||
# Sorting a list of tuples by starting with the last element of the tuple (=reversed tuple)
|
||||
|
||||
# Here, we make use of the "key" parameter of the in-built "sorted()" function
|
||||
# (also available for the ".sort()" method), which let's us define a function
|
||||
# that is called on every element that is to be sorted. In this case, our
|
||||
# "key"-function is a simple lambda function that returns the last item
|
||||
# from every tuple.
|
||||
|
||||
|
||||
a_list = [(1,3,'c'), (2,3,'a'), (3,2,'b'), (2,2,'b')]
|
||||
|
||||
sorted_list = sorted(a_list, key=lambda e: e[::-1])
|
||||
|
||||
print(sorted_list)
|
||||
|
||||
# prints [(2, 3, 'a'), (2, 2, 'b'), (3, 2, 'b'), (1, 3, 'c')]
|
||||
|
||||
|
||||
|
||||
# If we are only interesting in sorting the list by the last element
|
||||
# of the tuple and don't care about a "tie" situation, we can also use
|
||||
# the index of the tuple item directly instead of reversing the tuple
|
||||
# for efficiency.
|
||||
|
||||
|
||||
|
||||
a_list = [(1,3,'c'), (2,3,'a'), (3,2,'b'), (2,2,'b')]
|
||||
|
||||
sorted_list = sorted(a_list, key=lambda e: e[-1])
|
||||
|
||||
print(sorted_list)
|
||||
|
||||
# prints [(2, 3, 'a'), (3, 2, 'b'), (2, 2, 'b'), (1, 3, 'c')]
|
||||
|
|
@ -1,39 +0,0 @@
|
|||
# Sebastian Raschka 2014
|
||||
|
||||
"""
|
||||
You have 3 lists that you want to sort "relative" to each other,
|
||||
for example, picturing each list as a row in a 3x3 matrix: sort it by columns
|
||||
|
||||
########################
|
||||
If the input lists are
|
||||
########################
|
||||
|
||||
list1 = ['c','b','a']
|
||||
list2 = [6,5,4]
|
||||
list3 = ['some-val-associated-with-c','another_val-b','z_another_third_val-a']
|
||||
|
||||
########################
|
||||
the desired outcome is:
|
||||
########################
|
||||
|
||||
['a', 'b', 'c']
|
||||
[4, 5, 6]
|
||||
['z_another_third_val-a', 'another_val-b', 'some-val-associated-with-c']
|
||||
|
||||
########################
|
||||
and NOT:
|
||||
########################
|
||||
|
||||
['a', 'b', 'c']
|
||||
[4, 5, 6]
|
||||
['another_val-b', 'some-val-associated-with-c', 'z_another_third_val-a']
|
||||
|
||||
|
||||
"""
|
||||
|
||||
list1 = ['c','b','a']
|
||||
list2 = [6,5,4]
|
||||
list3 = ['some-val-associated-with-c','another_val-b','z_another_third_val-a']
|
||||
|
||||
|
||||
list1, list2, list3 = zip(*sorted(zip(list1, list2, list3)))
|
||||
|
|
@ -1,24 +0,0 @@
|
|||
# Sebastian Raschka, 03/2014
|
||||
# comparing string formating: %s and .format()
|
||||
|
||||
import timeit
|
||||
|
||||
format_res = timeit.timeit("['{}'.format(i) for i in range(10000)]", number=1000)
|
||||
|
||||
binaryop_res = timeit.timeit("['%s' %i for i in range(10000)]", number=1000)
|
||||
|
||||
print('{}: {}\n{}: {}'.format('format()', format_res, '%s', binaryop_res))
|
||||
|
||||
################################
|
||||
# On my machine
|
||||
################################
|
||||
#
|
||||
# Python 3.4.0
|
||||
# MacOS X 10.9.2
|
||||
# 2.5 GHz Intel Core i5
|
||||
# 4 GB 1600 Mhz DDR3
|
||||
#
|
||||
################################
|
||||
# format(): 2.815331667999999
|
||||
# %s: 1.630353775999538
|
||||
################################
|
||||
|
|
@ -1,24 +0,0 @@
|
|||
>>> import this
|
||||
"""
|
||||
The Zen of Python, by Tim Peters
|
||||
|
||||
Beautiful is better than ugly.
|
||||
Explicit is better than implicit.
|
||||
Simple is better than complex.
|
||||
Complex is better than complicated.
|
||||
Flat is better than nested.
|
||||
Sparse is better than dense.
|
||||
Readability counts.
|
||||
Special cases aren't special enough to break the rules.
|
||||
Although practicality beats purity.
|
||||
Errors should never pass silently.
|
||||
Unless explicitly silenced.
|
||||
In the face of ambiguity, refuse the temptation to guess.
|
||||
There should be one-- and preferably only one --obvious way to do it.
|
||||
Although that way may not be obvious at first unless you're Dutch.
|
||||
Now is better than never.
|
||||
Although never is often better than *right* now.
|
||||
If the implementation is hard to explain, it's a bad idea.
|
||||
If the implementation is easy to explain, it may be a good idea.
|
||||
Namespaces are one honking great idea -- let's do more of those!
|
||||
"""
|
||||
Loading…
Reference in New Issue
Block a user