Python Articles - Page 835 of 929

The binhex module encodes and decodes files in binhex4 format. This format is used in the representation of Macintosh files in ASCII. Only the data fork is handled.The binhex module defines the following functions −binhex.binhex(input, output): Convert a binary file with filename input to binhex file output. The output parameter can either be a filename or a file-like object (any object supporting a write() and close() method).binhex.hexbin(input, output): Decode a binhex file input. input may be a filename or a file-like object supporting read() and close() methods. The resulting file is written to a file named output unless the argument is None ... Read More

Context variable can have different values depending on its context. Unlike Thread-Local Storage where each execution thread may have a different value for a variable, a context variable may be several contexts in one execution thread. This is useful in keeping track of variables in concurrent asynchronous tasks.The ContextVar class is used to declare and work with Context Variables.import contextvars name = contextvars.ContextVar("name", default = 'Hello')The optional default parameter is returned by ContextVar.get() when no value for the variable is found in the current context.name: The name of the variable. This is a read-only property.Following methods are defined in ContextVar ... Read More

Files with '.plist' the extension is used by Mac OS X applications to store application properties. The plislib module provides an interface to read/write operations of these property list files.The plist file format serializes basic object types, like dictionaries, lists, numbers, and strings. Usually, the top level object is a dictionary. To write out and to parse a plist file, use the dump() and load() functions. Serialized byte strings are handled by use dumps() and loads() functions. Values can be strings, integers, floats, booleans, tuples, lists, dictionaries (but only with string keys).This module defines the following functions −load()Read a plist ... Read More

Functions in this module provide usefule information about live objects such as modules, classes, methods, functions, code objects etc. These functions perform type checking, retrieve source code, inspect classes and functions, and examine the interpreter stack.getmembers()− This function returns all the members of an object in a list of name, value pairs sorted by name. If the optional predicate is supplied, only members for which the predicate returns a true value are included. getmodulename() −This function returns the name of the module named by the file path, without including the names of enclosing packagesWe shall be using following script for ... Read More

The configparser module from Python's standard library defines functionality for reading and writing configuration files as used by Microsoft Windows OS. Such files usually have .INI extension.The INI file consists of sections, each led by a [section] header. Between square brackets, we can put the section’s name. Section is followed by key/value entries separated by = or : character. It may include comments, prefixed by # or ; symbol. A sample INI file is shown below −[Settings] # Set detailed log for additional debugging info DetailedLog=1 RunStatus=1 StatusPort=6090 StatusRefresh=10 Archive=1 # Sets the location of the MV_FTP log file LogFile=/opt/ecs/mvuser/MV_IPTel/log/MV_IPTel.log ... Read More

We are going to cover some useful python tricks and tips that will come handy when you are writing program in competitive programming or for your company as they reduce the code and optimized execution. Get n largest elements in a list using the module heapq Example import heapq marks = [91, 67, 34, 56, 78, 99, 87, 23, 78, 66] print("Marks = ", marks) print("Largest =", heapq.nlargest(2, marks)) Output Marks = [91, 67, 34, 56, 78, 99, 87, 23, 78, 66] Largest = [99, 91] Get n smallest elements in a list using the ... Read More

Image Processing Using OpenCVOpenCV(Open source computer vision) is an open source programming library basically developed for machine learning and computer vision. It provides common infrastructure to work on computer vision applications and to fasten the use of machine learning in commercial products.With more than 2.5 thousand optimized algorithms for both computer vision and machine learning are both classic and state-of-the-art algorithms. With so many algorithms, makes it to use the library for multiple purposes including face detection & recognization, identify objects, classify human actions in videos, track camera movements, join images together to produce a high resolution image of an ... Read More

The winsound module is specific to Python installation on Windows operating system. The module defines following functions −Beep()When this function is called a beep is heard from the PC’s speaker. The function needs two parameters. The frequency parameter specifies frequency of the sound, and must be in the range 37 through 32, 767 hertz. The duration parameter specifies duration of sound in .>>> import winsound >>> winsound.Beep(1000, 500)MessageBeep()This function plays a sound as specified in the registry. The type argument specifies which sound to play. Possible values are −-1, MB_ICONASTERISK, MB_ICONEXCLAMATION, MB_ICONHAND, MB_ICONQUESTION, and MB_OK (default).The value -1 produces a ... Read More

Indentation is an important feature of Python syntax. Code blocks in function, class or loops are required to follow same indent level for statements in it. The tabnanny module in Python's standard library is able to detect any violation in this stipulation.This module is primarily intended to be used in command line mode with –m switch. However, it can also be imported in an interpreter session.Command line usagepython –m tabnanny –q example.pyFor verbose output use –v switchpython –m tabnanny –v example.pyFollowing functions are defined in tabnanny module for checking indentation programmatically.check()This function checks for ambiguously indented lines in a given ... Read More

The sndhdr module in Python's standard library provides utility functions that read the type of sound data which is in a file. The functions return a namedtuple(), containing five attributesfiletypestring representing 'aifc', 'aiff', 'au', 'hcom', 'sndr', 'sndt', 'voc', 'wav', '8svx', 'sb', 'ub', or 'ul'.frameratethe sampling_rate will be either the actual value or 0 if unknown or difficult to decode.nchannelsnumber of channels or 0 if it cannot be determined or if the value is difficult to decodenframeseither the number of frames or -1.sampwidthbits_per_sample, will either be the sample size in bits or 'A' for A-LAW or 'U' for u-LAW.functions in sndhdr ... Read More