Analysing Equation in matlab

I am new to matlab and I made a graph of flight score against payload to find apoint where we can get max flight score but i ended up getting blank graph.

This is a code I used. Thank you very much for your time.

 nl = [1 , 2];
 ns = [2 , 3];
 payload = [300 , 400];
 x = 1*nl;
 y = 0.4*ns;
 bonus = [0.5 + (1 *nl) + (0.4 * ns)];
 T = [ 5 , 8];
 d = payload .* bonus;
 e = sqrt(d); 
 f = 80 * e;
 fs = f/T;
 plot(fs,payload)
 

[Johannes Hougaard]

I think this may well be one of the cases where it's kinda counterintuitive that / doesn't do what you think it does.

the '/' operator (mrdivide) is not identical to the './' operator (rdivide). I believe what you're looking for is the element-wise division (rdivide) and that your code should be

 nl = [1 , 2];
 ns = [2 , 3];
 payload = [300 , 400];
 x = 1*nl;
 y = 0.4*ns;
 bonus = [0.5 + (1 *nl) + (0.4 * ns)];
 T = [ 5 , 8];
 d = payload .* bonus;
 e = sqrt(d); 
 f = 80 * e;
 fs = f./T;
 plot(fs,payload)
 

Answer 1

[Ollie A]

Be careful when multiplying and dividing arrays; you will need to use the dot notation.

You remembered it for

d = payload .* bonus;

but it is also needed when dividing

fs = f./T;

I also find it helpful to plot data points as crosses:

plot(xdata,ydata,'x')
hold on
plot(xdata,ydata)

that way if you only have 1 data point it will still appear on the plot as a cross.

Also note: if you want flight score on the y-axis and payload on the x-axis, it will be

plot(payload,fs)

[Johannes Hougaard]

if you like the 'line with cross notation' it's not necessary to call the hold on and a second call to plot you can simple do that by

plot(xdata,ydata,'-x');