# NOT RUN {
inner(diag(7))
inner(matrix(1:9,3,3))
## Compare the following two:
Alt(inner(matrix(1:9,3,3))) # An alternating k tensor
as.kform(inner(matrix(1:9,3,3))) # Same thing coerced to a kform
f <- as.function(inner(diag(7)))
X <- matrix(rnorm(14),ncol=2) # random element of (R^7)^2
f(X) - sum(X[,1]*X[,2]) # zero to numerical precision
## verify positive-definiteness:
g <- as.function(inner(crossprod(matrix(rnorm(56),8,7))))
stopifnot(g(kronecker(rnorm(7),t(c(1,1))))>0)
# }
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