search for: derivy

Dear R Helpers: I am trying to annotate a plot. The following code snippet works, but it is kind of a kludge since it adds the partial derivative symbols after creating the plotmath frac(). Is there a more elegant way to write a partial derivative? dev.off() plot(NA, xlim=c(-3,3), ylim=c(0,1.6), xlab="", ylab="", tck=-0.015) text(1.6, 1, expression(paste("slope =

What functions exist for differentiating a numeric vector (in my case spectral data)? That is, experimental data without an analytical function. ie, > x <- seq(1,10,0.1) > y=x^3+rnorm(length(x),sd=0.01) #although the real function would be nothing simple like x^3... > derivy <- .... I know I could just use diff(y) but it would be nice to estimate derivatives at the endpoints, calculate higher-order derivatives, and maybe have some smoothing options ie by differentiating a spline or something like that.

Hello. I had previously posted a question concerning the optimization of a nonlinear function conditional on equality constraints. I was pointed towards the contrOptim function. However, I do not understand the syntax of this function with respect to specifying the constraints and so I don’t know if it is what I need. The command is: constrOptim(theta, f, grad,ui,ci,…). “theta” is the

A few days ago, I sent a question to the r-help list enquiring about the *** LEGALITY *** of porting a function from Splus into R. As a particular example, I referred to error.bar. Several people posted code for various versions of error.bar which they had written, but that was NOT WHAT I WAS ASKING FOR/ABOUT!!! [Can't anybody ***read*** these days?] I asked: IS IT

We have had some conversation within R core, lead by Duncan Murdoch and me, about a proposal to extend the current tracingState() functionality by something tentatively called debuggingState(). Duncan has allowed me to copy the previous conversation (after very minor editing): The following is quite technical and assumes you know more about R's debug()ing and trace()ing than an estimated

From: Matt Fleming <matt.fleming at intel.com> Since we can't use __intcall() for EFI, and since we can now have the ELF module code resolve all our symbols at runtime, we should delete as many references to __intcall() as possible and just access the symbols directly. The most interesting patch is the support for weak symbols. We need to be able to reference derivative-specific