Prev: Figure popunder?
Next: Making A Transfer Function Denominator Variable With Time
From: Ali Haider on 29 Apr 2010 07:05
I have written a function that calculates some variable "t":

function t=t_from_phi(phi, far)
i = 0;
t = exp((phi - 2.81661)/3.648659);
error = phi - phi(t, far);
while (abs(error) < 1e-06) || (i > 30)
i = i + 1;
error = phi - phi(t, far);
if(abs( error1) > 1e-06);
error2 = phi - phi((t+5), far);
t = t - error1 * 5/(error2 - error1);
end
end
end

the above function uses one more function "phi(t,far)" i.e.

function phig = phi(t,far)
phi_prod = 0.921799*log(abs(t)) + ...
((((((9.26961630e-23*t-1.1024117e-18)*t + ...
5.6284307e-15)*t-1.6093578e-11)*t + ...
2.8260446e-08)*t-3.2535245e-05)*t + ...
0.03217804 )*t+10.276527;

phi_air = 3.650244*log(abs(t)) + ...
((((((1.28948870e-23*t-1.2002500e-19)*t + ...
4.1981343e-16)*t-5.7867935e-13)*t - ...
1.9034645e-10)*t+1.5470500e-06)*t - ...
1.3521020e-03)*t+2.81661;

if (far == 0)
phig = phi_air;
else
phig = (phi_air + far*phi_prod)/(1 + far);
end
end

the values used in function 1:
phi = 23
the result value of t around 287.

when I tries to run the code it gives the error:
??? Subscript indices must either be real positive integers or
logicals.

Error in ==> t_from_phi at 5
error = phi - phi(t, far);

please help me out.

Check my first function!

Best Regards
Basharat
 | 
Pages: 1
Prev: Figure popunder?
Next: Making A Transfer Function Denominator Variable With Time