lyng/docs/math.md

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# Operators
## Precedence
Same as in C++.
| Priority | Operations |
|:----------------:|--------------------------------------|
| **Highest**<br>0 | power, not, calls, indexing, dot,... |
| 1 | `%` `*` `/` |
| 2 | `+` `-` |
| 3 | bit shifts `<<` `>>` |
| 4 | `<=>` (1) |
| 5 | `<=` `>=` `<` `>` |
| 6 | `==` `!=` |
| 7 | bitwise and `&` |
| 8 | bitwise xor `^` |
| 9 | bitwise or `\|` |
| 10 | `&&` |
| 11<br/>lowest | `\|\|` |
Bitwise operators
: available only for `Int` values. For mixed `Int`/`Real` numeric expressions, bitwise operators are not defined.
Bitwise NOT `~x`
: unary operator that inverts all bits of a 64‑bit signed integer (`Int`). It follows two's‑complement rules, so
`~x` is numerically equal to `-(x + 1)`. Examples: `~0 == -1`, `~1 == -2`, `~(-1) == 0`.
Examples:
```
5 & 3 // -> 1
5 | 3 // -> 7
5 ^ 3 // -> 6
~0 // -> -1
1 << 3 // -> 8
8 >> 3 // -> 1
```
Notes:
- Shifts operate on 64-bit signed integers (`Int` is 64-bit). Right shift `>>` is arithmetic (sign-propagating).
- Shift count is masked to the range 0..63, similar to the JVM/Kotlin behavior (e.g., `1 << 65` equals `1 << 1`).
(1)
: Shuttle operator: `a <=> b` returns 0 if a == b, negative Int if a < b and positive Int otherwise. It is necessary to
override shuttle operator to make a class comparable.
## Operators
`+ - * / % `: if both operand is `Int`, calculates as int. Otherwise, as real:
// integer division:
3 / 2
>>> 1
but:
3 / 2.0
>>> 1.5
## Round and range
The following functions return its argument if it is `Int`,
or transformed `Real` otherwise.
| name | description |
|----------------|--------------------------------------------------------|
| floor(x) | Computes the largest integer value not greater than x |
| ceil(x) | Computes the least integer value value not less than x |
| round(x) | Rounds x |
| x.roundToInt() | shortcut to `round(x).toInt()` |
## Lyng math functions
| name | meaning |
|-----------|------------------------------------------------------|
| sin(x) | sine |
| cos(x) | cosine |
| tan(x) | tangent |
| asin(x) | $sin^{-1}(x)$ |
| acos(x) | $cos^{-1}(x)$ |
| atan(x) | $tg^{-1}(x)$ |
| sinh(x) | hyperbolic sine |
| cosh(x) | hyperbolic cosine |
| tanh(x) | hyperbolic tangent |
| asinh(x) | $sinh^{-1}(x)$ |
| acosh(x) | $cosh^{-1}(x)$ |
| atanh(x) | $tgh^{-1}(x)$ |
| ln(x) | $ln(x)$, $ log_e(x) $ |
| exp(x) | $e^x$ |
| log10(x) | $log_{10}(x)$ |
| pow(x, y) | ${x^y}$ |
| sqrt(x) | $ \sqrt {x}$ |
| abs(x) | absolute value of x. Int if x is Int, Real otherwise |
For example:
assert( sin(π/2) == 1.0)
assert( cos(π/2) < 0.000001)
assert( abs(ln(exp(1))) - 1 < 0.00001)
// abs() keeps the argument type:
assert( abs(-1) is Int)
assert( abs(-2.21) == 2.21 )
>>> void
## Scientific constant
| name | meaning |
|----------------------|--------------|
| `Math.PI: Real` or π | 3.1415926... |
| | |
| | |
| | |