Problem with contour(): typo
On 29/09/2020 5:37 a.m., Helmut Sch?tz wrote:
Dear Duncan, Duncan Murdoch wrote on 2020-09-28 21:47:
You're doing a lot of manipulation of the z matrix; I haven't followed all of it, but that's where I'd look for problems.? Generally if you keep your calculation of the z matrix very simple you are better off. For example, once you have xs and ys in the form you want, calculate z as z <- outer(x,y, function(x,y) ...)
>> >> and then plot it using contour(x, y, z, ...) Sorry, that was a typo, should have been z <- outer(xs,ys, function(x,y) ...) contour(xs, ys, z)
The only tricky issue here is that the function needs to be vectorized, so if your power.TOST function doesn't accept vectors for CV and theta0, you'll need to put it in a wrapper that does (perhaps using the Vectorize function).
Here I'm lost. power.TOST(theta0, CV, ...) vectorizes properly for theta0 _or_ CV but no _both_. Hence library(PowerTOST) power.TOST(theta0 = c(0.9, 0.95, 1), CV = 0.25, n = 28) and power.TOST(theta0 = 0.95, CV = c(0.2, 0.25, 0.3), n = 28) work, whereas power.TOST(theta0 = c(0.9, 0.95, 1), 0.95, CV = c(0.2, 0.25, 0.3), n = 28) not. Of note, we will throw an error in the next release if both arguments are vectors.
I wouldn't do that, because it doesn't fit the usual R style. It's very common for functions to allow vector inputs in several arguments, and match up corresponding values to form a vector result.
I tried
f <- function(x, y) {
? power.TOST(theta0 = x, CV = y, n = 28)
}
x <- unique(sort(c(0.95, seq(0.95*0.95, 1, length.out = 28))))
y <- unique(sort(c(0.25, seq(0.25*0.8, 0.25*1.2, length.out = 28))))
Vectorize(f, c("x, y"), SIMPLIFY = "array")
which is obviously not correct.
If you want to use Vectorize, the command would be
power.TOST.vectorized <- Vectorize(power.TOST, c("theta0", "CV"))
A roughly equivalent version (without the recycling that Vectorize does)
would be
power.TOST.vectorized <- function(theta0, CV, ...) {
result <- length(theta0)
for (i in seq_along(theta0))
result[i] <- power.TOST(theta0[i], CV[i], ...)
result
}
Duncan Murdoch