Equivalent of MATLAB's unwrap

General Usage
1

Is there a Julia function that is equivalent to MATLAB’s unwrap? It is the function that shift angles by multiples of 2π to make them look distributed continuously.

2

Util - utility functions · DSP.jl, can also do more than 1 dimension.

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3

You can also use FFTViews which will use periodic boundary conditions when indexing.

4

If you don’t want to use an external package, you can easily define an equivalent function in Julia:

function unwrap!(x, period = 2π)
	y = convert(eltype(x), period)
	v = first(x)
	@inbounds for k = eachindex(x)
		x[k] = v = v + rem(x[k] - v,  y, RoundNearest)
	end
end

And then use array views if you want to operate along a specific dimension.

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5

FFTViews sounds great, but not sure how to use it to unwrap angles. Could you show me an example?

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That v[-4:3] in the README performs unwrapping.

8

I don’t think FFTViews is doing unwrapping that I want. In my problem the periodic boundary condition is applied to the values, not the indices. @jagot’s solution works for me.

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