FREE MATLAB Functions and Flow Control Questions and Answers

Question 1

A function `calculateArea` is defined as follows:

```matlab
function area = calculateArea(width, height)
    if nargin == 1
        % Assume a square if only one input is given
        height = width;
    end
    area = width * height;
end
```

What is the output of the command `calculateArea(5)`?

Accepted Answer

25

Answer

Error: Not enough input arguments.

Answer

0

Answer

5

Question 2

A script `mainScript.m` contains the following code:

```matlab
% mainScript.m
value = 10;
modifyValue(value);
disp(value);
```

The function `modifyValue` is defined in a separate file `modifyValue.m`:

```matlab
function modifyValue(inputArg)
    inputArg = inputArg + 5;
end
```

Assuming both files are in the current directory, what is displayed in the Command Window when `mainScript` is run?

Accepted Answer

10

Answer

15

Answer

An error is thrown because `value` is not returned.

Answer

5

Question 3

After executing the following code, what is the final value of `x`?

```matlab
x = 1;
n = 10;
while x <= n
    x = x * 2;
    n = n - 1;
end
```

Accepted Answer

8

Answer

16

Answer

4

Answer

10

Question 4

Consider the following function `countCalls`:

```matlab
function currentCount = countCalls()
    persistent callCounter;
    if isempty(callCounter)
        callCounter = 1;
    else
        callCounter = callCounter + 1;
    end
    currentCount = callCounter;
end
```

If the following commands are executed sequentially in the Command Window, what is the final value of `c`?

```matlab
countCalls();
countCalls();
c = countCalls();
```

Accepted Answer

3

Answer

1

Answer

2

Answer

An error occurs because `callCounter` is not initialized.

Question 5

A programmer needs to search a numeric vector `V` for the first element greater than 100 and store its index. Which code snippet correctly and most efficiently accomplishes this?

Accepted Answer

```matlab
targetIndex = -1;
for k = 1:length(V)
    if V(k) > 100
        targetIndex = k;
        break;
    end
end
```

Answer

```matlab
targetIndex = -1;
for k = 1:length(V)
    if V(k) > 100
        targetIndex = k;
    end
end
```

Answer

```matlab
targetIndex = -1;
for k = 1:length(V)
    if V(k) <= 100
        continue;
    end
    targetIndex = k;
end
```

Answer

```matlab
targetIndex = find(V > 100, 1, 'first');
continue;
```

Question 6

What is the value of `result` after this code is executed?

```matlab
value = 'medium';
switch value
    case {'low', 'minimum'}
        result = 1;
    case 'medium'
        result = 2;
    case 'high'
        result = 3;
    otherwise
        result = 0;
end
```

Accepted Answer

2

Answer

1

Answer

0

Answer

An error occurs because 'medium' is a string.

A function `calculateArea` is defined as follows:```matlabfunction area = calculateArea(width, height) if nargin == 1 % Assume a square if only one input is given height = width; end area = width * height;end```What is the output of the command `calculateArea(5)`?

A function `calculateArea` is defined as follows:
```matlab
function area = calculateArea(width, height)
if nargin == 1
% Assume a square if only one input is given
height = width;
end
area = width * height;
end
```
What is the output of the command `calculateArea(5)`?