math/abs
===============================================================================
%% Floating-point absolute value
1. Usage
-------------------------------------------------------------------------------
```mech:disabled
Y := math/abs(X)
```
2. Description
-------------------------------------------------------------------------------
Computes the absolute value of each element of `X`. The input `X` may be a scalar, vector, or matrix of floating-point values. The result `Y` has the same shape as the input `X`.
3. Input
-------------------------------------------------------------------------------
| Argument | Kind | Description |
|----------|--------------------------|---------------------------------------|
| `X` | `float`, `[float]` | Input floating-point value(s). Can be single or double precision. |
4. Output
-------------------------------------------------------------------------------
| Argument | Kind | Description |
|----------|--------------------------|---------------------------------------|
| `Y` | matches input | Absolute value of the input. The shape of `Y` matches the shape of `X`. |
5. Examples
-------------------------------------------------------------------------------
(a) Find the absolute value of a number
```mech:ex1
y := math/abs(-3.14)
```
(b) Find the absolute value for a vector of numbers
```mech:ex2
x := [-1.0, 0.0, 2.5]
y := math/abs(x)
```
(c) Find the absolute value for a matrix of numbers
```mech:ex3
x := [-1.0, 2.0; -3.0, 4.0]
y := math/abs(x)
```
6. Details
-------------------------------------------------------------------------------
The absolute value of a real number is defined as its distance from zero on the number line:
$$ |x| = \begin{cases} x & x \geq 0 \\ -x & x < 0 \end{cases}
This function applies element-wise to arrays and matrices of floating-point values.
For floating-point numbers, the result is always non-negative.
For complex numbers, the absolute value defined as the distance from the origin in the complex plane:
$$ |a + bi| = \sqrt{a^2 + b^2} $$
where `a` is the real part and `b` is the imaginary part of the complex number.