sunt05 / PJLink

JLink but for python: a link between Mathematica and python with efficient data transfer

‌

PJLink

PJLink is a package developed to link python and Mathematica

---

‌

Installation

The easiest way to install PJLink is using a paclet server installation:

PacletInstall[
  "PJLink",
  "Site"->
    "http://www.wolframcloud.com/objects/b3m2a1.paclets/PacletServer"
  ]

If you've already installed it you can update using:

PacletUpdate[
  "PJLink",
  "Site"->
    "http://www.wolframcloud.com/objects/b3m2a1.paclets/PacletServer"
  ]

Alternately you can download this repo as a ZIP file and put extract it in $UserBaseDirectory/Applications

---

‌

Usage

To start you need to call InstallPython to load a python runtime (the first time this is done it may be slow as it compiles the library PJLink uses for communication):

ker=InstallPython[];

After that you can evaluate python code as a string

PyEvaluateString["import numpy as np"];
PyEvaluateString["np.random.rand(5, 5, 5)"]~Short~3

(*Out:*)

{{{0.19340495587982665`,0.04333471882108819`,0.0793674077113492`,0.6746465215828963`,0.9128377509416972`},<<3>>,{0.36109338142334146`,0.44378058193673864`,<<19>>,<<21>>,0.5244287636275622`}},<<3>>,{<<1>>}}

You can also using the PJLink symbolic processing system to evaluate python code directly from Mathematica code. This is the best way to pass data into python:

With[{arr=RandomReal[{-1, 1}, {100, 100,100}]}, PyEvaluate[test=arr,  TimeConstraint->1]]//AbsoluteTiming//First

(*Out:*)

0.102152`

PyEvaluate[test]//Dimensions//AbsoluteTiming

(*Out:*)

{0.020897`,{100,100,100}}

Errors will be returned wrapped in PythonTraceback :

PyEvaluate[nosym]

(*Out:*)

PythonTraceback["Traceback (most recent call last):\n  File \"~/Documents/Python/IDEA/PJLink/PJLink/KernelLink.py\", line 654, in __handleCallPacket\n    self.__callPython()\n  File \"/Users/Mark/Documents/Python/IDEA/PJLink/PJLink/KernelLink.py\", line 1003, in __callPython\n    res = self.__do_call_recursive(pkt)\n  File \"~/Documents/Python/IDEA/PJLink/PJLink/KernelLink.py\", line 959, in __do_call_recursive\n    res = eval(arg, self.__EXEC_ENV, self.__EXEC_ENV)\n  File \"<string>\", line 1, in <module>\nNameError: name 'nosym' is not defined\n"]

When done, call ClosePython to clean up the runtime and close the link:

ClosePython[]