Installation

pip install cython

Using inside Jupyter notebook

Load th cythonmagic extension.


In [1]:
%load_ext cython

Then, simply use the magic function to start writing cython code.


In [2]:
%%cython

cdef int a = 0
for i in range(10):
    a += i
print(a)


45

Add --annotate or -a for showing a code analysis of the compiled code


In [3]:
%%cython --annotate

cdef int a = 0
for i in range(10):
    a += i
print(a)


45
Out[3]:
Cython: _cython_magic_6ba45f17d130910db2606828f4326b2d.pyx

Generated by Cython 0.25.2

Yellow lines hint at Python interaction.
Click on a line that starts with a "+" to see the C code that Cython generated for it.

 1: 
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/* … */
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