5,338 questions
Score of 0
0 answers
75 views
Cython profile fails when using a ctuple containing a pointer
Cython was failing to compile with profile = True and I narrowed it down as far as I could.
%%cython -a
#cython: profile=True
cdef class Foo:
cdef:
int bar
def __init__(self):
...
- reputation score 326
Score of 2
1 answer
37 views
How to extern templated version of std::bitset
I have successfully externed from std::bitset a specific-sized bitset type using the cython extern API:
cdef extern from "<bitset>" namespace "std" nogil:
cdef cppclass ...
- reputation score 326
Score of 0
4 answers
170 views
How do I convert .py file to a .pyd properly?
I have a simple .py file in a directory called core_app\functions\my_function.py like this:
from typing import Optional
from core_app.routes.models import (Model1, Model2, Model3)
from core_app.routes....
- reputation score 14341
Score of 4
1 answer
83 views
Cython memoryview pointer to empty array
The Cython docs discuss passing a pointer to a memoryview by using, e.g.:
cdef double[::1] x_view = x # some array
cdef double* ptr = &x_view[0]
however, when that array x has no elements (x....
- reputation score 404
Score of 0
1 answer
58 views
Cython memoryviews of Python object members with fused types
I am writing cython code with cython v3.1.5.
I have defined these fused types:
ctypedef fused index_t:
int32_t
int64_t
ctypedef fused value_t:
double
double complex
and am trying to ...
- reputation score 404
Score of 0
1 answer
54 views
Empty object instantiation in Cython
I am working on a Cython interface to a C library. I have this class:
cdef class CholeskyFactor:
cdef cholmod_factor *_factor
# ... etc.
def __cinit__(self, A, *, order=None, **kwargs):
...
- reputation score 404
Score of 20
2 answers
1587 views
How to set up a simple hello-world example where a C function calls a Cython function calling a Python function?
I am having trouble making a simple "Hello World" python function which I can call from a C program.
Here is the contents of my helloworld.py file:
def hw():
print("Hello World")
...
- reputation score 645
Score of 0
0 answers
45 views
Cython no module named error of own module
I am trying to compile a standalone executable from a Python project. It consists of several Python files written by me, with one Module being the "main" with the main function as the entry ...
- reputation score 145
Score of 3
2 answers
156 views
Cython Multiple Definitions of Function
I am using Cython to generate multiple C files from multiple Python files and then compile them using GCC. Using Python3.10 on Ubuntu 22.04 my tool flow works fine. When I switch to Kubuntu 20.04 with ...
- reputation score 145
Score of 0
0 answers
40 views
Cython: getline - unresolved externals?
I tried to use Cython to read a binary file line by line, but got errors during compiling the codes, due to, probably, getline. Simple test codes are as follows:
# test_getline_cython.pyx
cimport ...
- reputation score 648
Score of 1
2 answers
101 views
How to exploit sparsity with lists in a Cython function
I have a function I need to implement which does not vectorize well, and so I am implementing it in Cython to make the nested for-loops workable. My problem is of a similar complexity as naive matrix-...
- reputation score 53
Score of 0
0 answers
96 views
How to freeze Python build tools for repeatable builds?
TL;DR: When pip install builds and installs wheels, how do I determine which versions of build tool packages (e.g. Cython) it used? How do I force it to use the same versions of those packages in the ...
- reputation score 683
Score of 1
1 answer
89 views
profile=True not working on my machine, but is working in google colab
I am trying to get profile=True and %%prun to give a profile of the runtime for the compiled cython program. But on my Windows machine it is not working, the same code works on google colab. Cython ...
- reputation score 326
Score of 0
1 answer
59 views
Cython *.pxd file cannot use absolute imports for Cython submodule
I am getting an Error compiling Cython file, 'myproject/utils/hdf5.pxd' not found` when trying to build my Cython project in a certain way.
My Cython project is organized this way:
myproject/
setup....
- reputation score 374
Score of -1
1 answer
689 views
Python package install fails on docker image python:3.11-alpine : Error compiling cython file [closed]
I just had a problem that started Monday 12/05/2025, i have a custom python package on a registry that i've been using since a while, the installation of this package with pip on docker base image ...
- reputation score 74
