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Homework Help: MATLAB matrix question

  1. Jan 21, 2010 #1
    1. The problem statement, all variables and given/known data
    OK, so I have defined:

    n=[0:1:100];
    p=1.01; (but later will make this so it is inputted by user as a function)
    dx1=100*(p-1)/(p^101-1);
    dxn=p.^n*dx1;

    I need to define y1-y100 like:
    y0=1
    y1=1/(1+dxn(1))
    y2=1/(1+sum(dxn(1:2)))
    y3=1/(1+sum(dxn(1:3))) etc

    is there some way I can make this into some matrix with values up to y100 without having to write out and define each one individually? Maybe I'm being stupid but I can't see an easy way to do this. Any help would be much appreciated.
     
  2. jcsd
  3. Jan 22, 2010 #2

    Mark44

    Staff: Mentor

    I would use an intermediate array variable with 100 elements, and would store the values 1 + dxn(1), 1 + sum(dxn(1:2)), 1 + sum(dxn(1:3), etc. in it, up to 1 + sum(dxn(1:100). If you know about DO loops, you can do this very easily.

    After you have calculated all 100 values, store their reciprocals in y1, y2, ... , y100.
     
  4. Jan 22, 2010 #3

    for loop and empty 100 element long array?
    y=1/(1+sum(dxn(1:i)))
     
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