shafik

What is the Strict Aliasing Rule and Why do we care?

(OR Type Punning, Undefined Behavior and Alignment, Oh My!)

What is strict aliasing? First we will describe what is aliasing and then we can learn what being strict about it means.

In C and C++ aliasing has to do with what expression types we are allowed to access stored values through. In both C and C++ the standard specifies which expression types are allowed to alias which types. The compiler and optimizer are allowed to assume we follow the aliasing rules strictly, hence the term strict aliasing rule. If we attempt to access a value using a type not allowed it is classified as undefined behavior(UB). Once we have undefined behavior all bets are off, the results of our program are no longer reliable.

Unfortunately with strict aliasing violations, we will often obtain the results we expect, leaving the possibility the a future version of a compiler with a new optimization will break code we th

gilbert

/*
  Create this as a file ~/Library/KeyBindings/DefaultKeyBinding.dict
  Then restart your computer.
  NOTE: ~ means alt/option
        ^ means ctrl
*/
{
        "~f"="moveWordForward:";
        "~b"="moveWordBackward:";
        "~<"="moveToBeginningOfDocument:";

KevinCalderone

"""
Copyright 2017 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
https://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and

chaser92

# BEFORE STARTING PUT libcudnn5_5.1.10-1+cuda8.0_amd64.deb AND libcudnn5-dev_5.1.10-1+cuda8.0_amd64.deb IN /tmp
# OTHERWISE THIS WON'T WORK
# This has been tested only on EC2 P2 xlarge instance with 16 GB storage and stock Ubuntu 16.04
# It's a setup for a playground EC2 machine to perform workshops with Jupyter Notebook on GPU.
# It might contain some unnecessary crap
# The process takes like 15 minutes

pushd /tmp &&
stat libcudnn5_5.1.10-1+cuda8.0_amd64.deb &&
stat libcudnn5-dev_5.1.10-1+cuda8.0_amd64.deb &&

gyglim

"""Simple example on how to log scalars and images to tensorboard without tensor ops.

License: BSD License 2.0
"""
__author__ = "Michael Gygli"

import tensorflow as tf
from StringIO import StringIO
import matplotlib.pyplot as plt
import numpy as np

alexstaravoitau

#!/bin/bash

# Starts your AWS instance, connects via SSH and launches Chrome with the remote Jupyter Notebook page open.
# Usage is as follows:
# 1. Run this script, so that Chrome has launched and SSH connection is established.
# 2. Execute 'jupyter notebook' on the AWS instance.
# 3. Reload the page in Chrome and log in to Jupyter Notebook.
#
# Note: we use Chrome, as there's a known issue with Safari that won't let Jupyter Notebook connect to a remote kernel.
#

harpone

import tensorflow as tf
from tensorflow.python.framework import ops
import numpy as np

# Define custom py_func which takes also a grad op as argument:
def py_func(func, inp, Tout, stateful=True, name=None, grad=None):
    
    # Need to generate a unique name to avoid duplicates:
    rnd_name = 'PyFuncGrad' + str(np.random.randint(0, 1E+8))
    

vasanthk

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

1. Clarify and agree on the scope of the system

• User cases (description of sequences of events that, taken together, lead to a system doing something useful)
  • Who is going to use it?
  • How are they going to use it?

Avaq

const I  = x => x
const K  = x => y => x
const A  = f => x => f (x)
const T  = x => f => f (x)
const W  = f => x => f (x) (x)
const C  = f => y => x => f (x) (y)
const B  = f => g => x => f (g (x))
const S  = f => g => x => f (x) (g (x))
const S_ = f => g => x => f (g (x)) (x)
const S2 = f => g => h => x => f (g (x)) (h (x))

kashefy

'''
Created on Jul 13, 2015

@author: kashefy
'''
import numpy as np
from scipy import signal

if __name__ == '__main__':