R/00_mfd.R
inprod_mfd_diag.RdInner product of two multivariate functional data objects, for each observation
inprod_mfd_diag(mfdobj1, mfdobj2 = NULL)A multivariate functional data object of class mfd.
A multivariate functional data object of class mfd,
with the same number of functional variables and observations
as mfdobj1.
If NULL, then mfdobj2=mfdobj1. Default is NULL.
It calculates the inner product of two
multivariate functional data objects.
The main function inprod of the package fda
calculates inner products among
all possible couples of observations.
This means that, if mfdobj1 has n1 observations
and mfdobj2 has n2 observations,
then for each variable n1 X n2 inner products are calculated.
However, often one is interested only in calculating
the n inner products
between the n observations of mfdobj1 and
the corresponding n
observations of mfdobj2. This function provides
this "diagonal" inner products only,
saving a lot of computation with respect to using
fda::inprod and then extracting the
diagonal elements.
Note that the code of this function calls a modified version
of fda::inprod().
mfdobj <- data_sim_mfd()
inprod_mfd_diag(mfdobj)
#> [,1] [,2]
#> rep1 0.1460100 0.1132987
#> rep2 0.6338512 0.6130826
#> rep3 0.1701702 0.4554028
#> rep4 0.3491428 1.3387283
#> rep5 0.3957713 0.6253706