imaginary | ready HTTP microservice for high-level image processing | Computer Vision library

As stated in this answer, by creating a new table using the result of table.unpack:

There seem to be two points of confusion here:

1. What find_peaks is returning.
2. How to interpret complex values that the FFT is returning.

I will answer them separately.

find_peaks returns the indices in "a" that correspond to peaks, so I believe they ARE values you seek, however you must plot them differently. You can see the first example from the documentation here. But basically "peaks" is the index, or x value, and a[peaks] will be the y value. So to plot all your frequencies, and mark the peaks you could do:

The problem was that matplotlib changes its plotting strategy from 3.0.3 which ignores points with negative radius to 3.4.3 in which they're plotted.

I couldn't find this using compare release notes and it was so confusing for me. Hope there will be an warning for this situation avoiding future issues.

I tested bellow code which is way simpler:

In practice the backward reinterpreting will probably work most of the time, in view of the strong constraints of the forward reinterpreting impose (see on cppreference, std::complex, implementation notes).

However, I'm not totally sure that such backward reinterpreting would in always work in theory:

• Let's imagine an absurd and hypothetical implementation of a complex library that would maintain a list of addresses of active complex objects (e.g. for debugging purpose). This (probably static) list would be maintained by the complex constructor and destructor.
• Every complex operation in this library would verify if its operands are in the list.
• While forward reinterpreting would work (the complex objects were well constructed and its parts can be used as doubles), the backward reinterpretation would not work (e.g. despite a compatible layout, you would reinterpret as complex a pair of doubles and if you'd perform any complex operation on them, it would fail since the complex was not properly constructed, i.e. its address is not in the list).

As said, this complex library would probably be a stupid idea. But such a library could be implemented and compliant with the standard specs. This is sufficient to prove that there is no reverse guarantee in theory.

The last point of your question is easier and more obvious to answer, supposing we would have an implementation where the reverse reinterpretation works. The missing last column would lead to an access of a part that is out of bounds. This would therfore lead to UB.

Additional readings: This working paper of the standard committee requests a general convertability feature that would generalize the bahavior of reinterpret_cast on complex for other types. It explains the complex case in section 4 and the special handling required from the compiler to make it work if complex is not itself implemented by an array.

I edited your display_data function as below:

You can consider this example (it illustrates what Robert Dodier wrote in comments).

The following is an alternative approach, which does not use SUBQUERY, but should ultimately have the same results. I've no idea whether this would in practice be more or less efficient than using SUBQUERY.

Your specific concern is the inefficiency of counting all the matching Authors, rather than just stopping when the first matching Author is found. Bear in mind that there is a lot going on behind the scenes whenever a fetch request is processed. First, CoreData has to parse your predicate and turn it into an equivalent SQLite query, which will look something like this:

Neither the SE API nor SEDE provide such field. Instead, you can

One option is to create a logical array and then call Eigen::select on it. Inspired by https://forum.kde.org/viewtopic.php?f=74&t=91378

In this case: