Add bswap method for complex numbers. #21346
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It byte-swaps the real and imaginary parts individually, following what Fortran compilers do. The tests read the binary test data from an ad-hoc IOBuffer, because reinterpret doesn't work for complex numbers.
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Should this be documented e.g. in the docstring? The docstring currently only speaks about byte-swapping integers, but one can easily guess what it does for floating points. For complex numbers, OTOH, it could reasonably also swap real and imaginary parts (reading the whole thing backwards), no? |
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No, it wouldn't be reasonable to swap real and imaginary parts. endian-ness is a concept that applies only to real values taken individually. |
| @@ -167,6 +167,9 @@ function write(s::IO, z::Complex) | |||
| write(s,real(z),imag(z)) | |||
| end | |||
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| ## byte order swaps: real and imaginary part are swapped individually | |||
| bswap(z::Complex) = Complex(bswap(real(z)), bswap(imag(z))) | |||
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Actually, shouldn't this be Complex{<:Integer}?
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Not sure if we defined them but floating points have endianess too.
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bswap is defined for hardware floating-point values as well. I think it is appropriate to define this method for all Complex{T}, and let it fail with a bswap methoderror if the latter is not defined for T.
It byte-swaps the real and imaginary parts individually, following what Fortran compilers do.
The tests read the binary test data from an ad-hoc IOBuffer, because reinterpret doesn't work for complex numbers.
Originally I had this method in my own package FortranFiles.jl, but because this defines a Base method for a Base datatype, @tkelman suggested it might go into Base.