(from visualstudio-docs repo) "Call the DLL from Python" example not working #6931
Description
Possible bug in Call the DLL from Python, per this visualstudio-docs issue.
Here is that issue's original content:
When trying to run the Call the DLL from Python section, nothing gets printed on screen and the console simply prompts me to press any key. Upon closing the terminal, I get a Visual Studio error window, with the following description:
Could not convert to integer 3221225477, Path 'exitCode'. Value was either too large or too small for an Int32
For reference, I have only followed the PyBind11 section, and my .py and .cpp files are shown below:
main.py
from random import random
from time import perf_counter
from superfastcode import fast_tanh
COUNT = 500000 # Change this value depending on the speed of your computer
DATA = [(random() - 0.5) * 3 for _ in range(COUNT)]
e = 2.7182818284590452353602874713527
def sinh(x):
return (1 - (e ** (-2 * x))) / (2 * (e ** -x))
def cosh(x):
return (1 + (e ** (-2 * x))) / (2 * (e ** -x))
def tanh(x):
tanh_x = sinh(x) / cosh(x)
return tanh_x
def test(fn, name):
start = perf_counter()
result = fn(DATA)
duration = perf_counter() - start
print('{} took {:.3f} seconds\n\n'.format(name, duration))
for d in result:
assert -1 <= d <= 1, " incorrect values"
if __name__ == "__main__":
print('Running benchmarks with COUNT = {}'.format(COUNT))
test(lambda d: [tanh(x) for x in d], '[tanh(x) for x in d] (Python implementation)')
test(lambda d: [fast_tanh(x) for x in d], '[fast_tanh(x) for x in d] (PyBind11 C++ extension)')module.cpp:
#include <pybind11/pybind11.h>
#include <Windows.h>
#include <cmath>
const double e = 2.7182818284590452353602874713527;
double sinh_impl(double x) {
return (1 - pow(e, (-2 * x))) / (2 * pow(e, -x));
}
double cosh_impl(double x) {
return (1 + pow(e, (-2 * x))) / (2 * pow(e, -x));
}
double tanh_impl(double x) {
return sinh_impl(x) / cosh_impl(x);
}
namespace py = pybind11;
PYBIND11_MODULE(superfastcode, m) {
m.def("fast_tanh", &tanh_impl, R"pbdoc(
Compute a hyperbolic tangent of a single argument expressed in radians.
)pbdoc");
#ifdef VERSION_INFO
m.attr("__version__") = VERSION_INFO;
#else
m.attr("__version__") = "dev";
#endif
}I should not that the above error occurs during the import statement from superfastcode import fast_tanh.
Any clues? Thanks much in advance.