OK, simplifying it:
lat0 <- 42.61527
X <- 0.2023649
Z <- -0.9793102
Why does this give an error:
X <- X*cos(lat0) − Z*sin(-lat0)
## Error: unexpected input in "X <- X*cos(lat0) �"
and this doesn't?
X <- X*cos(42.61527) - Z*sin(-42.61527)
Here is the platform and R version:
platform x86_64-w64-mingw32
version.string R version 3.0.2 (2013-09-25)
I'm trying to implement this method