How can I properly enter this function in MATLAB

I keep trying to enter an equation in my MATLAB code, and i keep getting array indec errors or mismatched delimeters errors and I was wondering if someone could tell me how I could enter this function: P=p(a+b)(3-sqrt(3*a+b)(a+3*b))/a+b)) in MATLAB.

Answer 1

[Walter Roberson]

My guess is

P = p(a+b).*(3-sqrt(3*a+b).*(a+3*b)) ./ (a+b)

Answer 2

[DGM]

Three things:

1. The expression does have imbalanced parentheses
2. MATLAB doesn't support implicit multiplication of terms
3. I don't know the size of these variables

As a consequence of 2 and 3, I don't know whether the expression is supposed to be

P = p(a + b) ... % p is an array and a+b is the index into the array

or

P = p.*(a + b) ... % p is an array (or a scalar) being multiplied by the sum of a and b

Similarly, I can't really know what the intended parentheses is.

You can start by sorting out where the extra parentheses needs to be added/removed. Assuming the remaining operations are elementwise, you need to explicitly multiply the terms. Depending on what's intended, you might wind up with something like this.

P = p.*(a + b).*(3 - sqrt(3*a + b).*(a + 3*b))./a + b;

Bear in mind that's just a guess.