Skip to main content
Warning: You are using the test version of PyPI. This is a pre-production deployment of Warehouse. Changes made here affect the production instance of TestPyPI (testpypi.python.org).
Help us improve Python packaging - Donate today!

Fast float repr

Project Description

frepr

Fast float repr() for CPython using https://github.com/google/double-conversion. Approximately 8X faster than the built-in function.

Quick Start

>>> import frepr
>>> frepr.frepr(-1.8397892359791307e+134)
'-1.8397892359791307e+134'
>>> from timeit import timeit
>>> timeit('repr(-1.8397892359791307e+134)')
2.7296602272476758
>>> frepr.install()
>>> timeit('repr(-1.8397892359791307e+134)')
0.35723431229251545
>>> frepr.uninstall()

API

frepr.frepr(value)

Returns shortest string representation of a floating point value. The argument doesn’t have to be a float, as long as it is coercible to one (i.e. it has a __float__() method).

frepr.install()

Monkey-patches the Python runtime. Subsequent calls to repr() on floats will use the faster algorithm. This is safe to call multiple times.

frepr.uninstall()

Reverses the monkey-patching done by install(). Subsequent calls to repr() will use the original built-in algorithm. This is safe to call multiple times, even if install() was not called first.

Features

  • On average, approximately 8X faster than the standard function. (This result obtained on Python 3.6.0 64-bit/Windows 7/Intel Core i3 @ 2.93GHz. Test your own system with tests/perf.py).
  • Speeds up the standard json package (and any other library that relies on repr()).
  • Output is guaranteed to contain the shortest string of decimal digits necessary to uniquely identify the original IEEE 754 floating-point value.
  • Guaranteed to satisfy value == ast.literal_eval(frepr(value)).
  • Tested on CPython 2.6 through 3.6; probably works on other versions too.

Limitations

  • Currently, there is no support for alternative Python implementations (e.g. PyPy).
  • Output can be slightly different from the native function, due to floating-point rounding (but see accuracy guarantees above).
  • Has no effect on other built-in methods of converting floats to strings (e.g. str(), str.format(), "%f", "%g").

See Also

Release History

Release History

This version
History Node

0.1.1

History Node

0.1.0

Download Files

Download Files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

File Name & Checksum SHA256 Checksum Help Version File Type Upload Date
frepr-0.1.1-cp36-cp36m-win_amd64.whl (25.1 kB) Copy SHA256 Checksum SHA256 cp36 Wheel Feb 19, 2017
frepr-0.1.1.tar.gz (58.2 kB) Copy SHA256 Checksum SHA256 Source Feb 19, 2017

Supported By

WebFaction WebFaction Technical Writing Elastic Elastic Search Pingdom Pingdom Monitoring Dyn Dyn DNS Sentry Sentry Error Logging CloudAMQP CloudAMQP RabbitMQ Heroku Heroku PaaS Kabu Creative Kabu Creative UX & Design Fastly Fastly CDN DigiCert DigiCert EV Certificate Rackspace Rackspace Cloud Servers DreamHost DreamHost Log Hosting