Inner product of functions on an interval with Trapz.jl

General Usage
1 
x = range(0.,π,length = 1000)
u1 = sin.(x)
u2 = cos.(x)
ip = trapz(x,prod(hcat(u1,u2),dims=2))

AssertionError: Integration axis over yis incompatible withx. Make sure their length match!

Can’t figure out why it’s not compatible!

2

Works using NumericalIntegration with exact same syntax (defaults to trapezoid rule), changing trapz to integrate.

3

Trapz.jl works with input vector instead of 1000×1 Matrix:

trapz(x,prod(hcat(u1,u2),dims=2)[:])

However, it would be simpler to broadcast the product of two arrays:

trapz(x, u1 .* u2)
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4

Note that gaussian quadrature will likely be significantly faster.

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