Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Topic: sum of exponentials
Replies: 9   Last Post: Nov 24, 2012 7:16 PM

 Messages: [ Previous | Next ]
 dwi Posts: 17 Registered: 10/18/12
sum of exponentials
Posted: Nov 22, 2012 7:47 AM

I have a matrix whose data are interrupted by sequences of zeros. I need every time that there's a zero value to substitute it with a sum of exponentials using the previous data, eg:
x=[x1 x2 x3 0 0 0 x7 0 0]
When i find the first zero in the element x4 I want:
x4=(x3*e^(-1)+x2*e^(-2)+x1*e^(-3))/(e^(-1)+e^(-2)+e^(-3));
However, when I find the second zero value I need to calculate the same expression but without using the previous recalculated values. That is,
x4=x5=x6
and for x8 I will use only the values in x7,x3,x2,x1 and then x8=x9 etc
And all this for a 180000-length data.
Any ideas on how to do this?

Date Subject Author
11/22/12 dwi
11/22/12 Roger Stafford
11/23/12 dwi
11/23/12 dwi
11/23/12 dwi
11/23/12 dwi
11/23/12 Roger Stafford
11/24/12 dwi
11/24/12 Roger Stafford
11/24/12 dwi