logarithm

[PerBorgvad]

I need to compute the exponential of a arbitary logarithm in CVI.

In the term x=aö  x and a is known.

Can not find a function the computes n 

I do find log functions on bases 2 and 10, but n in my case differ from that.

Anyone ?

Regards Per Borgvad

[pincpanter]

This is a LabView forum, not CVI.
Anyway, let logn(x) be the logarithm of x, base n:
logn(x) = log(x)/log(n) = log10(x)/log10(n)

[PerBorgvad]

At the wrong place at the right time.

Anyway I do not follow, let me rephase :

(p0/p1) - (p0/p2) = a   known value

x = (dv/v)^n   also a known value

n= Help me out ?        

[pincpanter]

Sorry I'm not catching you. You mean that x is known? What are the variables here? And what's the relation between the two equations - they don't share any term...

[pincpanter]

I will make a guess for 2nd eq: you know x and (dv/v), you want to know n:

n = logbasedv/v (x) = log(x)/log(dv/v) = log10(x)/log10(dv/v)

is this what you need?

[PerBorgvad]

Thank you for your respons.

To clearify my problem

(p0/p1)-(p0/p2) = (dv/v)^n

p0,p1,p2,dv and v are known.

This is an hydraulic accumulator calculation where the intention is to see the effect

on n by varying the others.

Still n= ???

Regards Per

[pincpanter]

ok I understand now; the answer is in message 5, replacing x with (p0/p1)-(p0/p2):

n = log((p0/p1)-(p0/p2))/log(dv/v)