MartyConnelly
martyconnelly at shaw.ca
Sun Oct 30 13:08:50 CST 2005
Personally if I am using arrays or a lot of matrix math like Fourier Transforms. I develop in Intel Fortran Compiler for Windows & Visual Fortran but I can write Fortran in my sleep. It is COM compliant and callable from VBA. I have written DOS assembler a long time ago what I could do in a day in Fortran would take me 6 weeks in assembler just because I would have to relearn so much. Microsoft VB with arrays has a lot of overhead of error, type and range checking. Come to think of it IBM Fortran compilers and maybe others used to produce an optional ASM listing that might help you out. MartyConnelly wrote: >If you are working with really for sure definetely absolutely fixed size >arrays in VB6 dll you can >turn off Remove Array Bounds Checks option for about 25% speed >performance increase. >With the chance of a GPF > >Gustav Brock wrote: > > > >>Hi Fred >> >>Sounds interesting and in line with the comments from Mr. PowerBasic (Stuart). >> >>By the way, how did your brother-in-law write the Assembler version? With a tool of some sort or directly? >>Are you saying he obtained a 50:1 improvement in total compared to VB? >>I could probably handle PowerBasic without much trouble, but Assembler is far away ... >> >>/gustav >> >> >> >> >> >>>>>fahooper at trapo.com 29-10-2005 00:09 >>> >>>>> >>>>> >>>>> >>>>> >>My brother-in-law, who develops in VB6, has told me that writing his DLL's >>in PowerBasic gave him a 10:1 speed improvement. Then, for a couple of >>critical ones, he moved to Assembler for another 5:1. >> >>-----Original Message----- >>From: accessd-bounces at databaseadvisors.com >>[mailto:accessd-bounces at databaseadvisors.com] On Behalf Of Gustav Brock >>Sent: Friday, October 28, 2005 9:30 AM >>To: accessd at databaseadvisors.com >>Subject: [AccessD] Array faster in DLL? >> >>Hi all >> >>I have some routines that manipulate data in and between some arrays. >>The arrays are not large but they are recalculated about 3 mio. times which >>runs on my machine to 90 seconds. >> >>I was wondering if there would be any significant speed increase by moving >>these routines to a DLL. I have no experience in writing such libraries but >>guess I could find as the routines are uncomplicated. Variables are Long >>mostly, only one Single. >>It would take me some time to program these, of course, and if the speed >>increase only could be expected to be, say, 30%, it wouldn't hardly be worth >>it. >> >>Does anyone (Drew, Stuart?) have experience about what to expect? >> >>/gustav >> >> >> >> >> >> > > > -- Marty Connelly Victoria, B.C. Canada