Re: Inverse, numerical precision, simulation dynamical system

*To*: mathgroup at smc.vnet.net*Subject*: [mg77313] Re: [mg77211] Inverse, numerical precision, simulation dynamical system*From*: DrMajorBob <drmajorbob at bigfoot.com>*Date*: Wed, 6 Jun 2007 07:28:59 -0400 (EDT)*References*: <5452490.1181096373813.JavaMail.root@m35>*Reply-to*: drmajorbob at bigfoot.com

We haven't seen any of your code, so how could we know where to improve it? Certainly N[Inverse[x],1000] can't be faster than Inverse[x], since both require computing the Inverse. Bobby On Tue, 05 Jun 2007 06:01:17 -0500, kristoph <kristophs.post at web.de> wrote: > Dear Experts, > I am quiet new at the subject and would be grateful for a hint. > > I'm simulating a stochastic dynamical system which includes > calculating the inverse of (for now) a 2-by-2 matrix. At each > iteration these values are inputs for the next. Simply using > Inverse[.] does a very poor job considering timing. > > To speed up the process I used N[Inverse[.],1000]. It is better but > sometimes even a precision of 1000 is not enough resulting in an > "significant numerical error". > The dynamical system consists of 1000 iterations and I'm simulating it > 500-800 times for statistical reasons thus, time is an issue. > > Instead of using N[Inverse[.],1250] and so on for all iterations it > would be great if there is a way to speed up time and avoiding the > error. > > Thank you very much and all the best. > Kristoph > > > -- DrMajorBob at bigfoot.com