Hello all, I would like to maximize or minimize a given math function over a specific set of values.
I was checking out Wolfram Alpha (http://www70.wolframalpha.com/) and it can do simple optimization problems in math, such as maximize 15*x - x**2 over 0 to 15 (http://www70.wolframalpha.com/input/?i=maximize+15*x+-+x**2+over+0+to+15) which finds the maximum value and input for x in the range 0 to 15. Very cool. (This is of course a very simple example). Reading the R documentation I found out that with R I can do this: f<-function(x) (15*x)-x**2 optimize(f, c(0,15), lower=0,upper=15, maximum=TRUE) which works very nicely too! What I would like to do, but what Wolfram Alpha apparently can't do (according to a post in their community forum) is to maximize (or minimize) functions that contain two variables, x and y, or more. So for example a very simple example would be minimize x**2 + y**2 over x:0 to 15, y:0-12 -- this does not work -- though I'm unclear about -- the correct syntax too. Is there a way to do this in R in just a neat and easy way as R optimizes a 1-D function? For this particular instance I am interested in the minimum of x * sin(4*x) + 1.1 * sin(2*y), where x,y in range 0-10 so an example of this in R would be great, though in other problems the range may not be identical for x and y. Thanks, Esmail ps: Has anyone written any programs in Python that they then have used to call R functions? I am thinking of writing some of my scripts in Python, but then accessing some of R's functions. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
