calc_echo_times.m

function echo_times = calc_echo_times(num_echoes)

% caculate echo times
nseq = input('Does the data acquisition use one (1) or two (2) sequences?: ');
if nseq == 1
    uneven_flag = input('Is the echo spacing un-even? (y=1 / n=0): ');
    if uneven_flag == 0
        echo_times(1)=input('Enter the first echo time in ms: ');
        ES=input('Enter the echo spacing in ms: ');
        echo_times(2:num_echoes)=echo_times(1)+ES*(1:num_echoes-1);
    elseif uneven_flag == 1
        TE1 = input('Enter the first echo time in ms: ');
        ES1 = input('Enter the first echo spacing in ms: ');
        ES2 = input('Enter the second echo spacing in ms: ');
        num_echoes_1 = input('Enter the number of echoes used for the first echo spacing: ');
        num_echoes_2 = num_echoes - num_echoes_1;
        echo_times(1)= TE1;
        echo_times(2:num_echoes_1)=echo_times(1)+ES1*(1:num_echoes_1-1);
        echo_times((num_echoes_1+1):(num_echoes_1+num_echoes_2))=echo_times(num_echoes_1)+ES2*(1:num_echoes_2); 
    end
elseif nseq == 2
    echo_times(1)=input('Enter the first echo time in ms for sequence 1: ');
    s1ES=input('Enter the echo spacing in ms for sequence 1: ');
    echo_times(2)=input('Enter the first echo time in ms for sequence 2: ');
    s2ES=input('Enter the echo spacing in ms for sequence 2: ');    
    
    echo_times(3:2:num_echoes-1)=echo_times(1)+s1ES*(1:((num_echoes/2)-1));
    echo_times(4:2:num_echoes)=echo_times(2)+s2ES*(1:((num_echoes/2)-1));
end

end