All Questions
Tagged with numpy python-c-api
120 questions
0
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Python's C-extension with numpy randomly crashes after a few calls (5~10) from python code
To speed up custom MFCC calculations, I had to write some code in C, wrap it with Python's C API & numpy's C API, and compile it with disutils.core in order to import it from python code.
I was ...
- 33
1
vote
1
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94
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generalized ufunc on two arrays with one non-matching dimension
I want to write a numpy gufunc python extension using the numpy C-api that takes two matrices of arbitrary dimensionality, takes the mean across one dimension, and then subtracts one result from the ...
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36
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What is the standard method to numpy extension create modules that support different array datatypes?
Assuming I have a C function I would like to wrap by the Nympy(Python)-C API to create a Python extension module. This module should be capable of accepting Numpy array that can have multiple types ...
- 763
0
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65
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How to Import .py file with third-party package(like numpy) from C?
I'm using visual studio to import a python file from a c/c++ file to use a function(named lalala) defined in PythonApplication7.py. I'm trying to use Python-C-API to do this.
The C file is:
#include &...
- 1
0
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47
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Recursive Datatypes w/ Numpy C-API?
I'd like to use the numpy c-api to write a datatype that's a tree structure, with pointers to children. I initially thought this possible without being a flexible datatype, since I don't need a ...
- 31
-1
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2
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401
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What is the corresponding C-api name of the following numpy function in Python
I would like to write a C extension lib for Python, aiming to replace Python code with C.
The Python codes has several lines like below:
import numpy as np
a = np.array([1,3,12,0.43,234,-3,-4])
b = a[[...
- 319
4
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1
answer
226
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Linking to numpy's linear algebra libraries in C extension
I am writing a C extension and would like to take advantage of the linear algebra routines that the numpy libraries are linked to. Is there a cross platform method of getting the path for these? I've ...
- 300
0
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1
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283
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Include <arrayobject.h> header path to compile C python extension in build pipeline using cibuildwheels
I'm developing a python package that contains a C extension. I want to deploy a release for each operating system (linux, windows, macOS) using cibuildwheel. The C extension uses the arrayobject.h ...
- 1,198
1
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1
answer
1k
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Operate on Numpy array from C extension without memory copy
I'm new to C extensions for NumPy and I'm wondering if the following workflow is possible.
Pre-allocate an array in NumPy
Pass this array to a C extension
Modify array data in-place in C
Use the ...
1
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1
answer
532
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How to acquire GIL for the new thread state created using embed python in C++ application
I have a C++ application where we provide a python editor(which uses python 3.7), users can input and execute the python code in the editor. Following is the sample code where we are creating a new ...
- 69
4
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68
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Dymola Segfault in external C function with Python API when using time and numpy [duplicate]
We execute Python code from Dymola via the C/Python API. Therefore we used that tutorial. The tutorial works as shown, but when we combine Dymolas built-in time variable and Pythons Numpy library, we ...
- 51
0
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0
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447
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Numpy Python/C API - PyArray_SimpleNewFromData hangs
I'm figuring out the Python/C API for a more complex task. Initially, I wrote a simple example of adding two ndarrays of shape = (2,3) and type = float32.
I am able to pass two numpy arrays into c ...
- 493
1
vote
0
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146
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Writing my own ufunc; ufunc not supported for the input types
I'm trying to write a C function that coverts numpy string array to a float array. How can I receive numpy's array in C as const char *?
static void double_logitprod(char **args, npy_intp *dimensions,...
2
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2
answers
248
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Precomputing strided access pattern to array gives worse performance?
I have a written a c-extension for the numpy library which is used for computing a specific type of bincount. From the lack of a better name, let's call it fast_compiled and place the method signature ...
- 3,398
3
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0
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84
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No objects of __all__ are defined in numpy.random subpackage, but no errors are thrown upon importing
Why all the functions listed in __all__ (of the init file) of numpy.random subpackage work even though they aren't defined there?
I can imagine that they are written in C, but still when I do
from ...
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