One problem with using global variables is they could be accidentally deleted from the workspace, so it may be good to have the routine that checks if the block needs to be updated also check that the required global variables are still present in the workspace, and if not, regenerate them. I thought about just rounding the coefficients, but it seemed like it would only allow another power of two or so in spectrum length. Glenn
On 5/21/08, Jason Manley <[email protected]> wrote: > haha! Funny you should suggest this now. We've just had a meeting about this > string length limitation and the porting teams has decided that we will use > global variables to solve it. As a stop-gap (and to prevent matlab from > dying for unknown reasons), I've checked-in a version of the PFB to SVN that > brings up a warning box when the maximum string length is exceeded. There is > also an option to round-off coefficients now and save some space (else the > string contains 15 significant decimal places, which is excessive for most > 8-bit applications). > > Andrew Martens will be writing a guide for building future blocks, which > will mandate global variables for long strings and scripts to build the > blocks from scratch. It will probably include a template to help guys get > started. This will demonstrate the preferred method of passing variables to > sub-blocks etc. Also, I think safety checks (like the afore-mentioned string > length limit) are essential. Crashing Matlabs are not cool. > > Any further ideas? > > Jason > > > > > On 21 May 2008, at 02:05, G Jones wrote: > > > > > > Hi, > > This code seems to work for making long PFBs with the green blocks. It > > could probably be improved, but at least it's functional. Basically it > > assigns the 'buf' variable that contains the PFB coefficients to a > > unique name in the base Matlab workspace. I couldn't manage to get it > > to work assigning it in any other namespace. The unique name I chose > > is just related to the current time, so is meaningless. A more > > meaningful unique name could probably be constructed, but this was > > easy. Let me know if anyone has a better fix for this problem. > > Glenn > > <pfb_coeff_gen_init.m> > > > >
