1. Re: Matheval (was: Dos32Lib, Win32Lib)
- Posted by Beaumont Furniss <bfurniss at IHUG.CO.NZ> Jun 07, 2000
- 498 views
On 2000-06-06 EUPHORIA at LISTSERV.MUOHIO.EDU said: EU>[snip] EU>> EU>> Are right brackets automatically appended now , or are EU>>these EU>>seen as being unnecessary clutter. EU>> EU>I'm not sure what you mean here. EU>> when I entered an expression into eval.e , it returned EU>> something like EU>> this for the expression sin(x*(a*x+ , without the closing EU>>right bracketts. EU>Hmm...I think you might be confusing matheval with David Cuny's EU>eval.e. They're two separate packages. Matheval should return all EU>parenthesis correctly (in fact, the pretty print function will EU>probably add some parenthesis). I believe I am , this is what I downloaded , quite awhile ago ; with one of your attempts at using Davids' parser. EU>> I'm having some difficulty locating matheval EU>[snip] EU>> So where can I find the most recent version , I was unable EU>> to locate EU>> this on d.cunys website , certainly not within the more EU>> recent versions of EU>> dos32lib.* or win32lib.* . EU>Yup. Completely different. :) EU>It's on the recent contributions page. In fact, I just sent an EU>update to EU>http://members.xoom.com/matthewlewis/matheval.zip EU>It's about 32K. I added a graphing feature, and polished up the EU>parser to allow more flexible variable naming. After sending this message I shall attempt to download matheval.zip from that site. My browser doesn't support frames so there's , potentially , some difficulty. Is this in the form of *.ex and *.e files or a *.exe ? EU>> As you should be aware now , I uploaded this ; via email EU>> to you ; a few EU>> days ago. I understand , you might have numerous other EU>> concerns at this EU>> time , therefore you haven't evaluated this. EU>I did take a look at it yesterday (I suspect more reason for the EU>lag is our different locations on the globe--I'm in California). EU>It took a little bit to get it to work. Mainly the math.e part, EU>since some of the functions have been defined since EU 1.5 (arcsin, EU>etc). Very interesting, though. I like the way you evaluated the EU>function over the range, although that approach is incompatible to EU>matheval's way of doing things. Were you able to , easily , comprehend what I'd done though ? What's the weather like there ; have you had any unexpected storms ? Are you close to agricultural land ? I used EU 1.5 , because this is public domain , there might be a more recent version. Most functions can be described in terms of the basic ones , once you know how they're defined and used ; power() etc. I use -1<= x <=+1 , you can then use a multiple of x to extend the domain or add a value to x to shift the domain. for instance f(5*x) is from -5 to +5 , f(x+1) is from 0 to 2 ; f((x+1)/2) is from 0 to 1 and f(5*(x+1)/2) is from 0 to 5. Pre-assigning the domain to a sequence can , obviously , be extended to a number of dimensions. If you're attempting to actively select a region of the domain then your approach might well differ. EU>Take a look at the new graphing routines. They seem to run fairly EU>fast (at least on my PII 300), as long as you don't have too EU>complicated a function, and not too many iterations to calculate EU>(10000 goes pretty quickly). EU>Matt Lewis How fast did you find my software to be on your computer , you can put all of the files on ramdrive to gain a further increase in speed of evaluation. I'm hoping that the ability to evaluate complicated functions can be retained , while improving upon the speed of evaluation. To do so I need to expand my understanding of this whole area , we appear to have taken quite differing approaches ; this seems encouraging to me. I'd also like to put all of the software into one package that's platform independent. In the meantime I require some assistance on redirection . Net-Tamer V 1.11 - Test Drive