Vectorization with multiple conditionals

How can this be vectorized?

t is a monotonically increasing vector of floats. I'm basically dividing the array up into 5 regions and doing different calculations in each region.

out = zeros(length(t), 1);
for i = [1:1:lenght(t)]
    if t(i) < t1
        out(i) = 0;
        continue;
    elseif t(i) >= t1 && t(i) <= t2
        out(i) = 2 * t(i) + 3;
        continue;
    elseif t(i) > t2 && t(i) < t3
        out(i) = 1;
        continue;
    elseif t(i) >= t3 && t(i) <= t4
        out(i) = -5 * t(i) - 4
        continue;
    else % t > t4
        out(i) = 0;
        continue;
    end
end

Answer 1

[Star Strider]

Try this:

t1 = -5;
t2 = -1;
t3 =  5;
t4 =  8;
fcn = @(t) (t < t1).*0 + ((t >= t1) & (t <= t2)).*(2*t+3) + ((t > t2) & (t < t3)).*1 + ((t >= t3) & (t <= t4)).*(-5*t-4); 

t = linspace(-10, 10, 500);

figure
plot(t, fcn(t))
grid

Use your own values for ‘t1’ ... ‘t4’. This is simply an illustration.

.

[Marcus Rademacher]

That works beautifully and is lightning fast. Now that I see your solution it's obvious. Thanks for your help!

[Star Strider]

I very much appreciate your compliment!

As always, my pleasure!