[gouarin]

Checklist

• The title and commit message(s) are descriptive.
• Small commits made to fix your PR have been squashed to avoid history pollution.
• Tests have been added for new features or bug fixes.
• API of new functions and classes are documented (no public API changes).

Description

xview::element returned the wrong value when a newaxis comes before an integral slice:

xt::xarray<int> a = {{0, 1, 2}, {3, 4, 5}};
auto v = xt::view(a, xt::newaxis(), 1, xt::all());
v[{0, 2}];  // 3 instead of 5

make_index finds the slice k of each underlying dimension i, then the position of that slice in the view index: k minus the number of integral slices before it. It counted the integral slices before i instead of k. operator() already did it right.

xview.element_newaxis_before_integral fails on master and passes with the fix. I found this while writing a differential test for the xview_stepper fix, which used element() as its reference.

[codspeed]

Merging this PR will not alter performance

1 warning

⚠️ Unable to measure the execution of 1 benchmark

This benchmark measured no execution time, so its result is not comparable and counts as unchanged. This usually happens when the compiler removes the code under test.

Prevent compiler optimizations

See affected benchmarks

✅ 255 untouched benchmarks

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_{Comparing gouarin:fix-xview-element-newaxis (4b4e548) with master (57f3d07)}