Popular recipes tagged "meta:requires=sys"

Uno (Text-Based) (Python)

2017-07-15T00:46:59-07:00

Python recipe 580811 by Brandon Martin (artificial_intelligence, cards, game, text_game, uno).

A text based recreation of the classic card game featuring functional AIs to play with. Some rules have been modified. User interface is text based, non-curses, using only simple python commands to draw it.

Implementing class-based callbacks in Python (Python)

2017-04-20T23:34:50-07:00

Python recipe 580788 by Vasudev Ram (callbacks, classes, functions, methods, objects, programming, python).

This is a follow-on to this recently posted recipe:

Implementing function-based callbacks in Python: https://code.activestate.com/recipes/580787-implementing-function-based-callbacks-in-python/?in=user-4173351

This new recipe shows how to create and use callbacks in Python, using classes with methods, instead of plain functions, as was done in the recipe linked above. All other points such as reasons and benefits for using callbacks, are more or less the same as mentioned in the previous recipe, except that class instances can carry state around, so to that extent, the two approaches are different.

https://jugad2.blogspot.in/2017/04/python-callbacks-using-classes-and.html

How to create a simple PDF Pie Chart using fitz / PyMuPDF (Python)

2017-07-10T16:07:51-07:00

Python recipe 580810 by Jorj X. McKie (fitz, pdf_generation).

PyMuPDF now supports drawing pie charts on a PDF page.

Important parameters for the function are center of the circle, one of the two arc's end points and the angle of the circular sector. The function will draw the pie piece (in a variety of options) and return the arc's calculated other end point for any subsequent processing.

This example creates a chart of the parliament seat distribution for political parties in the current German Bundestag.

Unix tee-like functionality via a Python class (Python)

2017-03-31T14:30:30-07:00

Python recipe 580767 by Vasudev Ram (cli, command, commandline, linux, python, tee, unix, utilities, windows).

The Unix tee commmand, when used in a command pipeline, allows you to capture the output of the preceding command to a file or files, while still sending it on to standard output (stdout) for further processing via other commands in a pipeline, or to print it, etc.

This recipe shows how to implement simple tee-like functionality via a Python class. I do not aim to exactly replicate the functionality of the Unix tee, only something similar.

More details and sample output here:

https://jugad2.blogspot.in/2017/03/a-python-class-like-unix-tee-command.html

[xtopdf] Publish Delimiter-Separated Values (DSV data) to PDF (Python)

2016-12-17T19:08:33-08:00

Python recipe 580736 by Vasudev Ram (commandline, csv, data, files, formats, pdf, pdf_generation, python, tsv, utilities, xtopdf).

This recipe shows how to publish delimiter-separated values (a commonly used tabular data format) to PDF, using the xtopdf toolkit for PDF creation. It lets the user specify the delimiter via one of two command-line options - an ASCII code or an ASCII character. As Unix filters tend to do, it can operate either on standard input or on input filenames given as command-line arguments. In the case of multiple inputs via files, each input goes to a separate PDF output file.

A simple text file pager in Python (Python)

2017-02-10T21:34:45-08:00

Python recipe 580755 by Vasudev Ram (command, commandline, pagination, paging, python, text, utilities, windows).

This recipe shows how to create a simple text file pager in Python. It allows you to view text content a page at a time (with a user-definable number of lines per page). Like standard Unix utilities, it can either take a text file name as a command-line argument, or can read the text from its standard input, which can be redirected to come from a file, or to come from a pipe. The recipe is for Windows only, though, since it uses the msvcrt.getch() function, which is Windows-specific. However, the recipe can be modified to work on Unix by using things like tty, curses, termios, cbreak, etc.

More details here:

https://jugad2.blogspot.in/2017/02/tp-simple-text-pager-in-python.html

Convert wildcard text files to PDF with xtopdf (e.g. report*.txt) (Python)

2016-12-06T20:37:30-08:00

Python recipe 580727 by Vasudev Ram (conversion, files, globbing, patterns, pdf, pdfwriter, pdf_generation, text_processing, wildcard, xtopdf).

This recipe shows how to convert all text files matching a filename wildcard to PDF, using the xtopdf PDF creation toolkit. For example, if you specify report.txt as the wildcard, all files in the current directory that match report.txt, will be converted to PDF, each in a separate PDF file. The original text files are not changed.

Here is a guide to installing and using xtopdf:

http://jugad2.blogspot.in/2012/07/guide-to-installing-and-using-xtopdf.html

More details on running the program, and sample output, are available here:

http://jugad2.blogspot.in/2016/12/xtopdf-wildcard-text-files-to-pdf-with.html

Batch conversion of text files to PDF with fileinput and xtopdf (Python)

2016-11-07T20:28:01-08:00

Python recipe 580715 by Vasudev Ram (batch, batchmode, conversion, files, pdf, pdfwriter, python, text, text_processing, utilities, xtopdf).

This recipe shows how to do a batch conversion of the content of multiple text files into a single PDF file, with a) an automatic page break after the content of each text file (in the PDF output), b) page numbering, and c) a header and footer on each page.

It uses the fileinput module (part of the Python standard library), and xtopdf, a Python library for conversion of other formats to PDF.

xtopdf is available here: https://bitbucket.org/vasudevram/xtopdf

and a guide to installing and using xtopdf is here:

http://jugad2.blogspot.in/2012/07/guide-to-installing-and-using-xtopdf.html

Here is a sample run of the program:

python BTTP123.pdf text1.txt text2.txt text3.txt

This will read the content from the three text files specified and write it into the PDF file specified, neatly formatted.

Lines Of Code (LOC) (Python)

2016-10-25T17:53:01-07:00

Python recipe 580709 by Jean Brouwers (count, lines, python2, python3, source). Revision 3.

Count the number of lines (code, comment, blank) in one or several Python source files.

Read CSV with D and write it to PDF with Python (Python)

2016-10-26T17:49:00-07:00

Python recipe 580710 by Vasudev Ram (conversion, csv, data, files, formats, pdf, pdf_generation, xtopdf).

This recipe shows how to read data from a CSV file with a D program and write that data to a PDF file with a Python program - all in a single command-line invocation (after writing the individual programs, of course).

It requires the xtopdf toolkit, which you can get from:

https://bitbucket.org/vasudevram/xtopdf

Instructions for installing xtopdf:

http://jugad2.blogspot.in/2012/07/guide-to-installing-and-using-xtopdf.html

xtopdf in turn requires the open source version of the ReportLab toolkit, which you can get from:

http://www.reportlab.com/ftp (http://www.reportlab.com/ftp/reportlab-1.21.1.tar.gz)

It also requires the DMD compiler to compile the D program - this was the version used:

DMD32 D Compiler v2.071.2

Show OS error codes and messages from the os.errno module (Python)

2017-03-01T17:18:23-08:00

Python recipe 580759 by Vasudev Ram (commandline, introspection, libraries, python, unix, utilities, windows).

This recipe is a simple Python introspection utility that displays the defined OS error codes and messages (that Python knows about) from the os.errno module. It works for both Python 2 and Python 3. For each kind of OS error defined in Python, it will display a serial number, the error code, and the corresponding error name, and English error message. E.g. the first few lines of its output are shown below:

$ py -2 os_errno_info.py

Showing error codes and names

from the os.errno module:

Python sys.version: 2.7.12

Number of error codes: 86

Idx Code Name Message

0 1 EPERM Operation not permitted

1 2 ENOENT No such file or directory

2 3 ESRCH No such process

3 4 EINTR Interrupted function call

4 5 EIO Input/output error

More information, full output and other details are available here:

https://jugad2.blogspot.in/2017/03/show-error-numbers-and-codes-from.html

A utility like Unix seq (command-line), in Python (Python)

2017-01-08T17:48:57-08:00

Python recipe 580744 by Vasudev Ram (bash, command, commandline, linux, script, seq, sequence, shell, unix, utilities, utility).

This recipe shows how to create a utility like Unix seq (command-line), in Python. seq is described here:

https://en.wikipedia.org/wiki/Seq_(Unix)

but briefly, it is a command-line utility that takes 1 to 3 arguments (some being optional), the start, stop and step, and prints numbers from the start value to the stop value, on standard output. So seq has many uses in bigger commands or scripts; a common category of use is to quickly generate multiple filenames or other strings that contain numbers in them, for exhaustive testing, load testing or other purposes. A similar command called jot is found on some Unix systems.

This recipe does not try to be exactly the same in functionality as seq. It has some differences. However the core functionality of generating integer sequences is the same (but without steps other than 1 for the range).

More details and sample output are here:

https://jugad2.blogspot.in/2017/01/an-unix-seq-like-utility-in-python.html

The code is below.

A command-line musical alarm clock (Python)

2016-12-30T19:06:32-08:00

Python recipe 580739 by Vasudev Ram (alarm, audio, clock, multimedia, music, playsound, python, time, utilities, utility).

This is a simple musical alarm clock in Python. You pass a command-line argument specifying the time in minutes after which the alarm should go off. When that time arrives, it plays a musical sound.

Convert JSON to PDF with Python and xtopdf (Python)

2014-12-10T18:02:14-08:00

Python recipe 578979 by Vasudev Ram (json, pdfwriter, sys).

This recipe show the basic steps needed to convert JSON input to PDF output, using Python and xtopdf, a PDF creation toolkit. xtopdf is itself written in Pytho, and uses the ReportLab toolkit internally.

We set up some needed values, such as the output PDF file name, the font name and size, the header and footer, and the input lines for the body of the PDF output; all these values are passed in JSON format (in a single dictionary) to a function that uses those values to generate a PDF file with the desired content.

The code is intentionally kept simple so as to require the least amount of code needed to demonstrate the techniques involved. But it can be generalized or extended to more complex situations.

Give Python code a web plus command-line interface with hug (Python)

2017-01-05T16:57:15-08:00

Python recipe 580742 by Vasudev Ram (cli, commandline, hug, library, python, python3, user_interface, web, web_server).

This recipe shows how to take a Python function and wrap it with both a web and a command-line interface, somewhat easily, using the hug Python library. The example used shows how to wrap a function that uses the psutil library to get information on disk partitions. So you can see the disk partition info either via the web browser or the command line. The code for the recipe is shown below. It is also possible to wrap multiple functions in the same Python file, and expose all of them via both the web and the command-line.

More information and multiple sample outputs are available here:

https://jugad2.blogspot.in/2017/01/give-your-python-function-webcli-hug.html

Compute Memory footprint of an object and its contents (Python)

2012-11-23T23:57:31-08:00

Python recipe 577504 by Raymond Hettinger (memory, sizeof). Revision 3.

Recursive version sys.getsizeof(). Extendable with custom handlers.

A pseudo-echo, (or printf), function for any Python version. (Python)

2017-01-20T22:17:23-08:00

Python recipe 580750 by Barry Walker (amiga, apple, demo, echo, fs_uae, linux, printf, unix, windows, winuae).

A simple example of having a pseudo-echo using sys.stdout.write...

This gives exactly the same results from Python Versions, 1.4.0, 2.0.1, 2.5.6, 2.6.9, 3.4.3 and 3.5.2 on various platforms including the classic AMIGA A1200.

Enjoy finding simple solutions to often very difficult problems...

Bazza.

Get names and types of all attributes of a Python module (Python)

2016-10-06T17:21:42-07:00

Python recipe 580705 by Vasudev Ram (documentation, introspection, modules, reflection, type).

This recipe shows how to get the names and types of all the attributes of a Python module. This can be useful when exploring new modules (either built-in or third-party), because attributes are mostly a) data elements or b) functions or methods, and for either of those, you would like to know the type of the attribute, so that, if it is a data element, you can print it, and if it is a function or method, you can print its docstring to get brief help on its arguments, processsing and outputs or return values, as a way of learning how to use it.

The code for the recipe includes an example call to it, at the end of the code. Note that you first have to import the modules that you want to introspect in this way.

Simple directory list command with filename wildcard support (Python)

2016-12-02T20:52:56-08:00

Python recipe 580724 by Vasudev Ram (commandline, directory, file, filesystem, python, utilities).

This recipe shows a simple directory listing program. It can accept multiple command-line arguments specifying filenames. These filenames can include wildcard characters like * (asterisk) and ? (question mark), as is common in OS command shells like bash (Unix) and CMD (Windows). Tested on Windows but should work on Unix too, since it uses no OS-specific functions, or rather, it does use them, but that happens under the hood, within the libraries used.

Generate a PDF cheat sheet for converting 0 to 255 between bin / oct / dec / hex (Python)

2016-10-10T20:40:48-07:00

Python recipe 580706 by Vasudev Ram (binary, conversion, decimal, hexadecimal, octal, pdfwriter, pdf_generation, python, utility, xtopdf).

This recipe shows how to generate a PDF cheat sheet, that contains a table for conversion of the numbers 0 to 255 (the numbers that can fit in one byte) between binary, octal, decimal and hexadecimal representations. The table has four columns, one for each of those bases, and 256 rows, for the numbers 0 to 255.

TO use the table, you can look for a number, say in decimal, in the Dec(imal) column (or use the search function of your PDF viewer), then when you find it in some row, just look at the other 3 columns in that row, to find the value of that number in binary, octal and hexadecimal. And use the same procedure if starting with a number in any of the other three bases.