# tough to explain the subject...

Bram De Jong Bram.DeJong at rug.ac.be
Sat Jan 1 15:35:43 EST 2000

```Hi,

quite a while ago someone told me about a method to 'softly' go from one
value to the other:

v from a to b in N steps:

initialise:
v = a
dv = 0
ddv = c1
const = c2

loop
v += dv
dv += ddv
ddv += const

The trick is to set the right c1 and c2 (as the person said).
Well, I've been tinkering around with some equations, but I just can't
find it!!!
I've come as far as
c1 = 6*(b-a)/(N*N)
c2 = -12*(b-a)/(N*N*N)
But, it doesn't seem to work.
I've approched the problem via f(x)=ax**3 + bx**2 + cx + d but as it seems
the conversion from the continuous problem (df/dx, ...) to the discrete
problem makes my equations fail.

Can anybody help me?

Bram

<I ****think**** that it was Phil Burk who told me the method, but I am
NOT shure>

dupswapdrop -- the music-dsp mailing list and website: subscription info,
FAQ, source code archive, list archive, book reviews, dsp links
http://shoko.calarts.edu/musicdsp/

```