if statement with for loop

I am writing a function to calculate a value of p.

The formula is p=r*q + pa. The pa value is column vector which i have got from the ode45 function. I have to change the value of q w.r.t time i.e from 0 to 1 sec q=500, from 1 to 2 sec q=0.

I have written this program:

function [p] = fom(t,pa)
r=0.007;
tin=1;
t=0:0.01:2;

if t <=tin
    q = 600;
else t <= 2
    q = 0;
end

[t,pa]=ode45('FOM1',[t],[0])

for i=[palv]
    p=(r*q)+(i);
end

end

The problem is I am getting correct values after 1 sec in my output but before 1 sec where q is 0 values are not changing. Is this if statement correct?