Programming with Python
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Ironpython in Action
IronPytho IN ACTION Michael J. Foord Christian Muirhead FOREWORD BY JIM HUGUNIN MANNING IronPython in Action Download at Boykma.Com Licensed to Deborah Christiansen <[email protected]> Download at Boykma.Com Licensed to Deborah Christiansen <[email protected]> IronPython in Action MICHAEL J. FOORD CHRISTIAN MUIRHEAD MANNING Greenwich (74° w. long.) Download at Boykma.Com Licensed to Deborah Christiansen <[email protected]> For online information and ordering of this and other Manning books, please visit www.manning.com. The publisher offers discounts on this book when ordered in quantity. For more information, please contact Special Sales Department Manning Publications Co. Sound View Court 3B fax: (609) 877-8256 Greenwich, CT 06830 email: [email protected] ©2009 by Manning Publications Co. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by means electronic, mechanical, photocopying, or otherwise, without prior written permission of the publisher. Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in the book, and Manning Publications was aware of a trademark claim, the designations have been printed in initial caps or all caps. Recognizing the importance of preserving what has been written, it is Manning’s policy to have the books we publish printed on acid-free paper, and we exert our best efforts to that end. Recognizing also our responsibility to conserve the resources of our planet, Manning books are printed on paper that is at least 15% recycled and processed without the use of elemental chlorine. -
The Essentials of Stackless Python Tuesday, 10 July 2007 10:00 (30 Minutes)
EuroPython 2007 Contribution ID: 62 Type: not specified The Essentials of Stackless Python Tuesday, 10 July 2007 10:00 (30 minutes) This is a re-worked, actualized and improved version of my talk at PyCon 2007. Repeating the abstract: As a surprise for people who think they know Stackless, we present the new Stackless implementation For PyPy, which has led to a significant amount of new insight about parallel programming and its possible implementations. We will isolate the known Stackless as a special case of a general concept. This is a Stackless, not a PyPy talk. But the insights presented here would not exist without PyPy’s existance. Summary Stackless has been around for a long time now. After several versions with different goals in mind, the basic concepts of channels and tasklets turned out to be useful abstractions, and since many versions, Stackless is only ported from version to version, without fundamental changes to the principles. As some spin-off, Armin Rigo invented Greenlets at a Stackless sprint. They are some kind of coroutines and a bit of special semantics. The major benefit is that Greenlets can runon unmodified CPython. In parallel to that, the PyPy project is in its fourth year now, and one of its goals was Stackless integration as an option. And of course, Stackless has been integrated into PyPy in a very nice and elegant way, much nicer than expected. During the design of the Stackless extension to PyPy, it turned out, that tasklets, greenlets and coroutines are not that different in principle, and it was possible to base all known parallel paradigms on one simple coroutine layout, which is as minimalistic as possible. -
Method, 224 Vs. Typing Module Types
Index A migration metadata, 266 running migrations, 268, 269 Abstract base classes, 223 setting up a new project, 264 @abc.abstractmethod decorator, 224 using constants in migrations, 267 __subclasshook__(...) method, 224 __anext__() method, 330 vs. typing module types, 477 apd.aggregation package, 397, 516, 524 virtual subclasses, 223 clean functions (see clean functions) Actions, 560 database, 254 analysis process, 571, 572 get_data_by_deployment(...) config file, 573, 575 function, 413, 416 DataProcessor class, 561 get_data(...) function, 415 extending, 581 plot_sensor(...) function, 458 IFTTT service, 566 plotting data, 429 ingesting data, 567, 571 plotting functions, 421 logs, 567 query functions, 417 trigger, 563, 564 apd.sensors package, 106 Adafruit, 42, 486 APDSensorsError, 500 Adapter pattern, 229 DataCollectionError, 500 __aenter__() method, 331, 365 directory structure, 108 __aexit__(...) method, 331, 365 extending, 149 Aggregation process, 533 IntermittentSensorFailureError, 500 aiohttp library, 336 making releases, 141 __aiter__() method, 330 sensors script, 32, 36, 130, 147, 148, Alembic, 264 153, 155, 156, 535 ambiguous changes, 268 UserFacingCLIError, 502 creating a new revision, 265 apd.sunnyboy_solar package, 148, current version, 269 155, 173 downgrading, 268, 270 API design, 190 irreversible, migrations, 270 authentication, 190 listing migrations, 269 versioning, 240, 241, 243 merging, migrations, 269 589 © Matthew Wilkes 2020 M. Wilkes, Advanced Python Development, https://doi.org/10.1007/978-1-4842-5793-7 INDEX AssertionError, -
Python Concurrency
Python Concurrency Threading, parallel and GIL adventures Chris McCafferty, SunGard Global Services Overview • The free lunch is over – Herb Sutter • Concurrency – traditionally challenging • Threading • The Global Interpreter Lock (GIL) • Multiprocessing • Parallel Processing • Wrap-up – the Pythonic Way Reminder - The Free Lunch Is Over How do we get our free lunch back? • Herb Sutter’s paper at: • http://www.gotw.ca/publications/concurrency-ddj.htm • Clock speed increase is stalled but number of cores is increasing • Parallel paths of execution will reduce time to perform computationally intensive tasks • But multi-threaded development has typically been difficult and fraught with danger Threading • Use the threading module, not thread • Offers usual helpers for making concurrency a bit less risky: Threads, Locks, Semaphores… • Use logging, not print() • Don’t start a thread in module import (bad) • Careful importing from daemon threads Traditional management view of Threads Baby pile of snakes, Justin Guyer Managing Locks with ‘with’ • With keyword is your friend • (compare with the ‘with file’ idiom) import threading rlock = threading.RLock() with rlock: print "code that can only be executed while we acquire rlock" #lock is released at end of code block, regardless of exceptions Atomic Operations in Python • Some operations can be pre-empted by another thread • This can lead to bad data or deadlocks • Some languages offer constructs to help • CPython has a set of atomic operations due to the operation of something called the GIL and the way the underlying C code is implemented • This is a fortuitous implementation detail – ideally use RLocks to future-proof your code CPython Atomic Operations • reading or replacing a single instance attribute • reading or replacing a single global variable • fetching an item from a list • modifying a list in place (e.g. -
Thread-Level Parallelism II
Great Ideas in UC Berkeley UC Berkeley Teaching Professor Computer Architecture Professor Dan Garcia (a.k.a. Machine Structures) Bora Nikolić Thread-Level Parallelism II Garcia, Nikolić cs61c.org Languages Supporting Parallel Programming ActorScript Concurrent Pascal JoCaml Orc Ada Concurrent ML Join Oz Afnix Concurrent Haskell Java Pict Alef Curry Joule Reia Alice CUDA Joyce SALSA APL E LabVIEW Scala Axum Eiffel Limbo SISAL Chapel Erlang Linda SR Cilk Fortan 90 MultiLisp Stackless Python Clean Go Modula-3 SuperPascal Clojure Io Occam VHDL Concurrent C Janus occam-π XC Which one to pick? Garcia, Nikolić Thread-Level Parallelism II (3) Why So Many Parallel Programming Languages? § Why “intrinsics”? ú TO Intel: fix your #()&$! compiler, thanks… § It’s happening ... but ú SIMD features are continually added to compilers (Intel, gcc) ú Intense area of research ú Research progress: 20+ years to translate C into good (fast!) assembly How long to translate C into good (fast!) parallel code? • General problem is very hard to solve • Present state: specialized solutions for specific cases • Your opportunity to become famous! Garcia, Nikolić Thread-Level Parallelism II (4) Parallel Programming Languages § Number of choices is indication of ú No universal solution Needs are very problem specific ú E.g., Scientific computing/machine learning (matrix multiply) Webserver: handle many unrelated requests simultaneously Input / output: it’s all happening simultaneously! § Specialized languages for different tasks ú Some are easier to use (for some problems) -
Uwsgi Documentation Release 1.9
uWSGI Documentation Release 1.9 uWSGI February 08, 2016 Contents 1 Included components (updated to latest stable release)3 2 Quickstarts 5 3 Table of Contents 11 4 Tutorials 137 5 Articles 139 6 uWSGI Subsystems 141 7 Scaling with uWSGI 197 8 Securing uWSGI 217 9 Keeping an eye on your apps 223 10 Async and loop engines 231 11 Web Server support 237 12 Language support 251 13 Release Notes 317 14 Contact 359 15 Donate 361 16 Indices and tables 363 Python Module Index 365 i ii uWSGI Documentation, Release 1.9 The uWSGI project aims at developing a full stack for building (and hosting) clustered/distributed network applica- tions. Mainly targeted at the web and its standards, it has been successfully used in a lot of different contexts. Thanks to its pluggable architecture it can be extended without limits to support more platforms and languages. Cur- rently, you can write plugins in C, C++ and Objective-C. The “WSGI” part in the name is a tribute to the namesake Python standard, as it has been the first developed plugin for the project. Versatility, performance, low-resource usage and reliability are the strengths of the project (and the only rules fol- lowed). Contents 1 uWSGI Documentation, Release 1.9 2 Contents CHAPTER 1 Included components (updated to latest stable release) The Core (implements configuration, processes management, sockets creation, monitoring, logging, shared memory areas, ipc, cluster membership and the uWSGI Subscription Server) Request plugins (implement application server interfaces for various languages and platforms: WSGI, PSGI, Rack, Lua WSAPI, CGI, PHP, Go ...) Gateways (implement load balancers, proxies and routers) The Emperor (implements massive instances management and monitoring) Loop engines (implement concurrency, components can be run in preforking, threaded, asynchronous/evented and green thread/coroutine modes. -
How to Access Python for Doing Scientific Computing
How to access Python for doing scientific computing1 Hans Petter Langtangen1,2 1Center for Biomedical Computing, Simula Research Laboratory 2Department of Informatics, University of Oslo Mar 23, 2015 A comprehensive eco system for scientific computing with Python used to be quite a challenge to install on a computer, especially for newcomers. This problem is more or less solved today. There are several options for getting easy access to Python and the most important packages for scientific computations, so the biggest issue for a newcomer is to make a proper choice. An overview of the possibilities together with my own recommendations appears next. Contents 1 Required software2 2 Installing software on your laptop: Mac OS X and Windows3 3 Anaconda and Spyder4 3.1 Spyder on Mac............................4 3.2 Installation of additional packages.................5 3.3 Installing SciTools on Mac......................5 3.4 Installing SciTools on Windows...................5 4 VMWare Fusion virtual machine5 4.1 Installing Ubuntu...........................6 4.2 Installing software on Ubuntu....................7 4.3 File sharing..............................7 5 Dual boot on Windows8 6 Vagrant virtual machine9 1The material in this document is taken from a chapter in the book A Primer on Scientific Programming with Python, 4th edition, by the same author, published by Springer, 2014. 7 How to write and run a Python program9 7.1 The need for a text editor......................9 7.2 Spyder................................. 10 7.3 Text editors.............................. 10 7.4 Terminal windows.......................... 11 7.5 Using a plain text editor and a terminal window......... 12 8 The SageMathCloud and Wakari web services 12 8.1 Basic intro to SageMathCloud................... -
Goless Documentation Release 0.6.0
goless Documentation Release 0.6.0 Rob Galanakis July 11, 2014 Contents 1 Intro 3 2 Goroutines 5 3 Channels 7 4 The select function 9 5 Exception Handling 11 6 Examples 13 7 Benchmarks 15 8 Backends 17 9 Compatibility Details 19 9.1 PyPy................................................... 19 9.2 Python 2 (CPython)........................................... 19 9.3 Python 3 (CPython)........................................... 19 9.4 Stackless Python............................................. 20 10 goless and the GIL 21 11 References 23 12 Contributing 25 13 Miscellany 27 14 Indices and tables 29 i ii goless Documentation, Release 0.6.0 • Intro • Goroutines • Channels • The select function • Exception Handling • Examples • Benchmarks • Backends • Compatibility Details • goless and the GIL • References • Contributing • Miscellany • Indices and tables Contents 1 goless Documentation, Release 0.6.0 2 Contents CHAPTER 1 Intro The goless library provides Go programming language semantics built on top of gevent, PyPy, or Stackless Python. For an example of what goless can do, here is the Go program at https://gobyexample.com/select reimplemented with goless: c1= goless.chan() c2= goless.chan() def func1(): time.sleep(1) c1.send(’one’) goless.go(func1) def func2(): time.sleep(2) c2.send(’two’) goless.go(func2) for i in range(2): case, val= goless.select([goless.rcase(c1), goless.rcase(c2)]) print(val) It is surely a testament to Go’s style that it isn’t much less Python code than Go code, but I quite like this. Don’t you? 3 goless Documentation, Release 0.6.0 4 Chapter 1. Intro CHAPTER 2 Goroutines The goless.go() function mimics Go’s goroutines by, unsurprisingly, running the routine in a tasklet/greenlet. -
IMPLEMENTING OPTION PRICING MODELS USING PYTHON and CYTHON Sanjiv Dasa and Brian Grangerb
JOURNAL OF INVESTMENT MANAGEMENT, Vol. 8, No. 4, (2010), pp. 1–12 © JOIM 2010 JOIM www.joim.com IMPLEMENTING OPTION PRICING MODELS USING PYTHON AND CYTHON Sanjiv Dasa and Brian Grangerb In this article we propose a new approach for implementing option pricing models in finance. Financial engineers typically prototype such models in an interactive language (such as Matlab) and then use a compiled language such as C/C++ for production systems. Code is therefore written twice. In this article we show that the Python programming language and the Cython compiler allows prototyping in a Matlab-like manner, followed by direct generation of optimized C code with very minor code modifications. The approach is able to call upon powerful scientific libraries, uses only open source tools, and is free of any licensing costs. We provide examples where Cython speeds up a prototype version by over 500 times. These performance gains in conjunction with vast savings in programmer time make the approach very promising. 1 Introduction production version in a compiled language like C, C++, or Fortran. This duplication of effort slows Computing in financial engineering needs to be fast the deployment of new algorithms and creates ongo- in two critical ways. First, the software development ing software maintenance problems, not to mention process must be fast for human developers; pro- added development costs. grams must be easy and time efficient to write and maintain. Second, the programs themselves must In this paper we describe an approach to tech- be fast when they are run. Traditionally, to meet nical software development that enables a single both of these requirements, at least two versions of version of a program to be written that is both easy a program have to be developed and maintained; a to develop and maintain and achieves high levels prototype in a high-level interactive language like of performance. -
Faster Cpython Documentation Release 0.0
Faster CPython Documentation Release 0.0 Victor Stinner January 29, 2016 Contents 1 FAT Python 3 2 Everything in Python is mutable9 3 Optimizations 13 4 Python bytecode 19 5 Python C API 21 6 AST Optimizers 23 7 Old AST Optimizer 25 8 Register-based Virtual Machine for Python 33 9 Read-only Python 39 10 History of Python optimizations 43 11 Misc 45 12 Kill the GIL? 51 13 Implementations of Python 53 14 Benchmarks 55 15 PEP 509: Add a private version to dict 57 16 PEP 510: Specialized functions with guards 59 17 PEP 511: API for AST transformers 61 18 Random notes about PyPy 63 19 Talks 65 20 Links 67 i ii Faster CPython Documentation, Release 0.0 Contents: Contents 1 Faster CPython Documentation, Release 0.0 2 Contents CHAPTER 1 FAT Python 1.1 Intro The FAT Python project was started by Victor Stinner in October 2015 to try to solve issues of previous attempts of “static optimizers” for Python. The main feature are efficient guards using versionned dictionaries to check if something was modified. Guards are used to decide if the specialized bytecode of a function can be used or not. Python FAT is expected to be FAT... maybe FAST if we are lucky. FAT because it will use two versions of some functions where one version is specialised to specific argument types, a specific environment, optimized when builtins are not mocked, etc. See the fatoptimizer documentation which is the main part of FAT Python. The FAT Python project is made of multiple parts: 3 Faster CPython Documentation, Release 0.0 • The fatoptimizer project is the static optimizer for Python 3.6 using function specialization with guards. -
Jupyter Tutorial Release 0.8.0
Jupyter Tutorial Release 0.8.0 Veit Schiele Oct 01, 2021 CONTENTS 1 Introduction 3 1.1 Status...................................................3 1.2 Target group...............................................3 1.3 Structure of the Jupyter tutorial.....................................3 1.4 Why Jupyter?...............................................4 1.5 Jupyter infrastructure...........................................4 2 First steps 5 2.1 Install Jupyter Notebook.........................................5 2.2 Create notebook.............................................7 2.3 Example................................................. 10 2.4 Installation................................................ 13 2.5 Follow us................................................. 15 2.6 Pull-Requests............................................... 15 3 Workspace 17 3.1 IPython.................................................. 17 3.2 Jupyter.................................................. 50 4 Read, persist and provide data 143 4.1 Open data................................................. 143 4.2 Serialisation formats........................................... 144 4.3 Requests................................................. 154 4.4 BeautifulSoup.............................................. 159 4.5 Intake................................................... 160 4.6 PostgreSQL................................................ 174 4.7 NoSQL databases............................................ 199 4.8 Application Programming Interface (API).............................. -
High-Performance Computation with Python | Python Academy | Training IT
Training: Python Academy High-Performance Computation with Python Training: Python Academy High-Performance Computation with Python TRAINING GOALS: The requirement for extensive and challenging computations is far older than the computing industry. Today, software is a mere means to a specific end, it needs to be newly developed or adapted in countless places in order to achieve the special goals of the users and to run their specific calculations efficiently. Nothing is of more avail to this need than a programming language that is easy for users to learn and that enables them to actively follow and form the realisation of their requirements. Python is this programming language. It is easy to learn, to use and to read. The language makes it easy to write maintainable code and to use it as a basis for communication with other people. Moreover, it makes it easy to optimise and specialise this code in order to use it for challenging and time critical computations. This is the main subject of this course. CONSPECT: Optimizing Python programs Guidelines for optimization. Optimization strategies - Pystone benchmarking concept, CPU usage profiling with cProfile, memory measuring with Guppy_PE Framework. Participants are encouraged to bring their own programs for profiling to the course. Algorithms and anti-patterns - examples of algorithms that are especially slow or fast in Python. The right data structure - comparation of built-in data structures: lists, sets, deque and defaulddict - big-O notation will be exemplified. Caching - deterministic and non-deterministic look on caching and developing decorates for these purposes. The example - we will use a computionally demanding example and implement it first in pure Python.