Compute the inner product of two functional data objects.
<f, g> = integral(f(t) * g(t) dt)
Usage
inprod.fdata(fdata1, fdata2 = NULL)
Arguments
- fdata1
First functional data object.
- fdata2
Second functional data object. If NULL, computes inner
products of fdata1 with itself.
Value
A matrix of inner products. If fdata1 has n1 curves and fdata2
has n2 curves, returns an n1 x n2 matrix.
Examples
t <- seq(0, 1, length.out = 100)
X1 <- matrix(sin(2*pi*t), nrow = 1)
X2 <- matrix(cos(2*pi*t), nrow = 1)
fd1 <- fdata(X1, argvals = t)
fd2 <- fdata(X2, argvals = t)
# Inner product of sin and cos over [0,1] should be 0
inprod.fdata(fd1, fd2)
#> [,1]
#> [1,] 2.218175e-17