GaelVaroquaux

Cython example of exposing C-computed arrays in Python without data copies

The goal of this example is to show how an existing C codebase for numerical computing (here c_code.c) can be wrapped in Cython to be exposed in Python.

The meat of the example is that the data is allocated in C, but exposed in Python without a copy using the PyArray_SimpleNewFromData numpy

jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

swannodette

;; based on http://talks.golang.org/2012/concurrency.slide#50

(ns robpike
  (:require [cljs.core.async :as async :refer [<! >! chan close!]])
  (:require-macros [cljs.core.async.macros :as m :refer [go alt!]]))

(defn timeout [ms]
  (let [c (chan)]
    (js/setTimeout (fn [] (close! c)) ms)
    c))

lelandbatey

Description

This simple script will take a picture of a whiteboard and use parts of the ImageMagick library with sane defaults to clean it up tremendously.

The script is here:

#!/bin/bash
convert "$1" -morphology Convolve DoG:15,100,0 -negate -normalize -blur 0x1 -channel RBG -level 60%,91%,0.1 "$2"

Results

saaj

# -*- coding: utf-8 -*-
'''
Ranking code based on:
  https://github.com/coleifer/peewee/blob/master/playhouse/sqlite_ext.py
'''


import struct
import math

gubatron

Things to remember when compiling/linking C/C++ software

by Angel Leon. March 17, 2015;

Last update on December 14, 2023

Updated on February 27, 2023

Updated August 29, 2019.

taoari

#!/usr/bin/env python
import caffe
from caffe.proto import caffe_pb2
from google.protobuf import text_format

class structtype:
    pass

def loadSolver(fn):
    with open(fn) as f:

aaronhoffman

// source: https://msdn.microsoft.com/en-us/library/bb259689.aspx
//------------------------------------------------------------------------------
// <copyright company="Microsoft">
//     Copyright (c) 2006-2009 Microsoft Corporation.  All rights reserved.
// </copyright>
//------------------------------------------------------------------------------

using System;
using System.Text;