Вячеслав Безбородов. Julia vs. Python

Я расскажу об особенностях использования языка Julia и языка Python для решения вычислительных задач большой размерности, с примерами кода и комментариями.

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2. Julia vs. Python
   Doing your math
   

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3. What is Julia?
   

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4. A language for technical computing
   Julia features
   ● Multiple dispatch
   ● Dynamic type system
   ● Call Python functions
   ● Call C functions directly (no wrappers or special APIs needed)
   ● Designed for parallelism and distributed computation
   ● Efficient support for Unicode, including but not limited to UTF-8
   ● Free and open source (MIT licensed)
   History remark
   Julia was first appeared in 2012. It’s a young language with quite small, but quickly
   growing community.
   WIKI
   It is a flexible dynamic
   language, appropriate for
   scientific and numerical
   computing, with performance
   comparable to traditional
   statically-typed languages.
   

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6. Travis CI
   

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7. REPL
   

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11. Julia is not Python
    

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12. 1-based indexing
    In Julia, indexing of arrays, strings, etc. is 1-based not 0-based.
    Julia does not support negative indexes.
    In particular, the last element of a list or array is indexed with end in Julia, not -1 as in Python.
    Indentation level is not significant as it is in Python.
    Julia's for, if, while, etc. blocks are terminated by the end keyword.
    Julia arrays are column major (Fortran ordered) whereas NumPy arrays are row major
    (C-ordered) by default
    To get optimal performance when looping over arrays, the order of the loops should be reversed in Julia relative to NumPy.
    Julia requires end to end a block.
    Unlike Python, Julia has no pass keyword.
    In Julia % is the remainder operator, whereas in Python it is the modulus.
    Noteworthy differences from Python
    

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13. Calculations
    

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18. Going parallel
    

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27. Networking
    

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28. Nothing is impossible. Let’s write a server!
    

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31. Further reading
    ● https://julialang.org/
    ● http://www.laketide.com/julia-vs-r-vs-python/
    ● https://www.quora.com/What-are-the-disadvantages-of-Julia-compared-to-Python
    ● https://medium.com/@Jernfrost/python-vs-julia-observations-e61ee667fa95
    ● https://modelingguru.nasa.gov/docs/DOC-2625
    

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32. VYACHESLAV BEZBORODOV
    PROGRAMMER
    +7 919 407 10 66
    vyacheslav.bezborodov@gmail.com
    v.bezborodov@pressfoto.ru
    THANK YOU!
    

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