Math Functions & Extensibility

SmartCal includes a comprehensive set of built-in mathematical functions and provides an extension API via FunctionRegistry.

Built-in Functions

The following standard mathematical functions are available by default in all expressions:

Function	Description	Example
abs(x)	Absolute value	abs(-15) $\rightarrow$ 15
sqrt(x)	Square root	sqrt(16) $\rightarrow$ 4
round(x)	Round to nearest integer	round(3.6) $\rightarrow$ 4
floor(x)	Round down	floor(3.9) $\rightarrow$ 3
ceil(x)	Round up	ceil(3.1) $\rightarrow$ 4
min(a, b, ...)	Minimum of a list of numbers	min(10, 5, 20) $\rightarrow$ 5
max(a, b, ...)	Maximum of a list of numbers	max(10, 5, 20) $\rightarrow$ 20
sin(x)	Sine (in radians)	sin(0) $\rightarrow$ 0
cos(x)	Cosine (in radians)	cos(0) $\rightarrow$ 1
tan(x)	Tangent (in radians)	tan(0) $\rightarrow$ 0
log(x)	Natural logarithm (base $e$)	log(1) $\rightarrow$ 0
exp(x)	Exponential ($e^x$)	exp(1) $\rightarrow$ 2.718...

Example in a formula:

import SmartCal from 'smartcal';

const hypotenuse = SmartCal('sqrt(a ^ 2 + b ^ 2)', { a: 3, b: 4 });
console.log(hypotenuse); // 5

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Registering Custom Functions (FunctionRegistry)

You can extend SmartCal by registering your own custom business functions:

import { FunctionRegistry, compile } from 'smartcal';

// 1. Register a custom function
FunctionRegistry.register('clamp', (val, min, max) => {
  return Math.min(Math.max(val, min), max);
});

// 2. Use the function in any expression
const clampSpeed = compile('clamp(speed, 0, 130)');

console.log(clampSpeed.evaluate({ speed: 150 })); // 130
console.log(clampSpeed.evaluate({ speed: -10 })); // 0
console.log(clampSpeed.evaluate({ speed: 90 }));  // 90

FunctionRegistry Utility Methods

// Check if a function is available
FunctionRegistry.has('clamp'); // true

// Get the underlying function
const fn = FunctionRegistry.get('clamp');

// Remove a custom function
FunctionRegistry.unregister('clamp');

// Reset all custom functions
FunctionRegistry.clearCustom();