General polynomial in VB6 without Excel?

[acjeff]

Hi,

Is it possible? I have 2 sets of data for X and Y. I want a VB6 program to general a trendline with 4th order polynomial equation automatically and then take all the coefficients for other purposes. However, the machine do not have Excel installed. Can I still do that?

Jeff

 

[EBGreen]

Can I do that?"

Yes

How?

No clue. You would have to essentially re-write the same algorithm that Excel uses in your own code.

[red]"... isn't sanity really just a one trick pony anyway?! I mean, all you get is one trick, rational thinking, but when you are good and crazy, oooh, oooh, oooh, the sky is the limit!" - The Tick[/red]

 

[HughLerwill]

acjeff,

I got my answer back in the 1980's from a book called BASIC PROGRAMS FOR SCIENTISTS AND ENGINEERS (specifically Figure 7.5) by Alan R. Miler - Pub Sibex 1981 - ISBN 0-89588-073-3 - the code in in BASICA but conversion to vb6 is pretty straight-forward.

I still have that answer running in vb6 but it is not easy and the code is too lengthy to post here. If you are serious and you email me via the address given at

http://www.gradlab.com

I will send you some stuff. I hope this does not break any forum rules.

Otherwise checkout 'Gauss-Jordan Parabolic Least Squares fit' in books or Google (although I have'nt tried the latter yet)

regards Hugh

 

[HughLerwill]

It looks as if a copy of the old book is available at

http://www.abebooks.co.uk/abe/BookDetailsPL?bi=622277544&isbn=0895880733

Hugh