How do I fix my code when the index exceeds the number if array elements?

drag(t)=findDrag(velocity(t),dragCoefficient,density(t),surfaceA);

function [DRAG] = findDrag (velocity,density,dragCoefficient,surfaceA)

%findDrag Calculate the force of Drag on the rocket

%Detailed explanation goes here

DRAG = (1/2)*((velocity)^2)*(density)*dragCoefficient*surfaceA;

end

Answer 1

[Image Analyst]

What is the value of t when you call it?

What are the lengths of the velocity and density vectors?

t must be less than the length of the velocity and density vectors.

[madhan ravi]

+1 made it clear

Answer 2

[madhan ravi]

change drag(t) to drag

[Image Analyst]

If t is valid, then drag(t) should be okay. What we need to know is the value of t. If it's undefined, or zero, or a negative number, or a fractional number, then that's a problem. It sounds like t is some positive number, like 10 or whatever, but that the velocity and density arrays do not have t elements in them, like velocity and density have only 4 elements in them instead of 10.

[madhan ravi]

Exactly sir Image Analyst but as I can see the operator * inside the function DRAG returned is just a scalar so there‘s no point in indexing drag(t) although maybe it should be .* only the OP can clarify it

[Image Analyst]

madhan, this code works just fine:

vec = zeros(1, 10) 
vec(8) = MyFunction(999)

function output = MyFunction(inputArg)
output = inputArg;
end

It will assign 999 to the 8th element of vec. You don't even need to initialize vec if you don't want to. This also works just fine:

vec(8) = MyFunction(999)

function output = MyFunction(inputArg)
output = inputArg;
end

It will create a vector of 8 elements and assign 999 to the 8th element.

However, this doesn't

v = zeros(1, 5);
t = 55;
vec(8) = MyFunction(999, v(t))

function output = MyFunction(inputArg, d)
output = inputArg;
end

and that is the problem he is having.

[madhan ravi]

yes , thank you for making it clear , really an expert advice! :)