Interpolation and getting errors

I am trying to run the piece of code below

function output = AtheroEqn2016(t,y,e)
  fid= fopen('ifng.txt','r');
  format longg;
  A = textscan(fid, ['%s', repmat('%f', 1 , 25)], 'HeaderLines', 1);
  e= [A{2:end}];
  time=[0 30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600 630 660 690 720]

    e= (((t-time(floor(t/30)))/(time(floor(t/30)+1)-time(floor(t/30))))*e1) + (((time(floor(t/30)+1)-t)/(time(floor(t/30)+1)-time(floor(t/30)+1)))*e0)

howver when it gets to the last line I get the following error, _ * _ Subscript indices must either be real positive integers or logicals._*_

Does anyone know why this is and how I could fix it?

Thanks

Answer 1

[Jan Orwat]

Note, you are trying to access time(0) when t<30. Matlab index arrays starting with 1. Probably changing floor(t/30) to ceil(t/30) or to floor(t/30)+1 would fix this error.

[Jan Orwat]

btw. you will get the same time vector by typing time = 0:30:720;

[C Mck]

thanks