Resources for OOP in Matlab.

Hi,

I started looking into OOP matlab, and I'm fairly confused.

Could you share any useful resaurses to help me learn the classes within matlab?

Below I have a demonstration of what I'm trying to do, if you think the resoucrse I might need are specific. But, other than that it can be ignored.

Overall, the resources I found are very vain, don't have enough code examples, or jump too far ahead for starting to learn. Using matlab 2019a.

Currently I'm trying to make a programs into which you input a value you want find, let sat 'Velocity2', and input a range of known value by the use of an specific equation.

The equation is the Energy balance for steady flow: Q1-Q2+W1-W2=m(h2-h1 + V1^2/2 - V2^2/2 + g(z2-z1))

Where h2-h1 can be replaced with cp(t2-t1) or g(z2-z1) can be replaced with GE, depending on what is imputed into the equation.

This means the program will ask you for:

Value to solve for:

what is the value for X:

In the second question you can answer a double to input a know value or assumption, or n saying it is unknown. This would change the value of an objects property to the said value or leave/change it to empty if n was inputted. However, I cannot get it to work yet as I'm struggling with the Object and classes part and I'm uncertin if I should use a method for somethin or not.

For example below is a set of code I have but it gives me one of two problems.

Data; % The Class name with properties inside it
props = properties(Data);
for iprop = 1:length(props)
    thisprop = props{iprop};
    R = input( "value for " + thisprop + "? ", 's');
    if ((R ~= 'N') || (R ~= 'n')) && (isnumeric(double(R)))
        Data.(thisprop) = double(R);
    end
end

Problem one, if you enter the value 'n' it will still set the specific property value as 'n'. Whereas I would prefer it to be left empty or set to empty (not yet code the elseif).

Problem two, it does not go through all the value after 'n' or a larger number is written and gives the message:

"Operands to the || and && operators must be convertible to logical scalar values.

Error in Energy_equation (line 22)

if (((R ~= 'N') || (R ~= 'n')) && (isnumeric(double(R))))"

Once, again I'm mainly looking for resource rather than a specific solution.

Answer 1

[Samatha Aleti]

Hi,

You may refer the following MATLAB document links to have a good understanding on developing classes in MATLAB:

Simple example

Typical workflow

Refer the following link to understand how to deal with dependent properties in MATLAB:

Dependent properties

Hope this helps!