How to Sum a loop and Then Loop that Sum

Sorry for the confusing title,

So lets say i have 2 sets of data;

a= 4, 8, 9, 11, 13

d = 0.2, 0.3, 0.5, 0.6, 0.8

the equation i want results from is: a * d * (1 - (d / (2 * a) ))

so i want to get the sum of all these equations together:

a1 * d1 * (1 - (d1 / (2 * a1) ))

a2 * d1 * (1 - (d1 / (2 * a2) ))

a3 * d1 * (1 - (d1 / (2 * a3) ))

a4 * d1 * (1 - (d1 / (2 * a4) ))

a5 * d1 * (1 - (d1 / (2 * a5) ))

so the sum of all of these would be my first value.

The next value would be the sum of all these equations:

a1 * d2 * (1 - (d2 / (2 * a1) ))

a2 * d2 * (1 - (d2 / (2 * a2) ))

a3 * d2 * (1 - (d2 / (2 * a3) ))

a4 * d2 * (1 - (d2 / (2 * a4) ))

a5 * d2 * (1 - (d2 / (2 * a5) ))

The next value the sum of these:

a1 * d3 * (1 - (d3 / (2 * a1) ))

a2 * d3 * (1 - (d3 / (2 * a2) ))

a3 * d3 * (1 - (d3 / (2 * a3) ))

a4 * d3 * (1 - (d3 / (2 * a4) ))

a5 * d3 * (1 - (d3 / (2 * a5) ))

and so on.. until i have 5 values

Thank you

Answer 1

[Guillaume]

a = [4, 8, 9, 11, 13];
d = [0.2, 0.3, 0.5, 0.6, 0.8];

d = d.';  %transpose d so it's a column vector
result = a .* d .* (1 - d ./ (2*a))

columns of result correspond to the elements of a, rows to the elements of d. This uses the implicit expansion introduced in R2016b

[Todd Trainor]

Hello thank you for your answer,

If i were to sum these up using this code, how could i then put these 5 values into a vector?

for x = 1:5
    sum(result(x,1:5))
end

[Guillaume]

You don't need a loop

result = a .* d .* (1 - d ./ (2*a));
sumresult = sum(result, 2)  %sum across the columns