Context API

MathFlow configuration is managed through the properties of a context.

This provides a simple interface for solving, rendering, and managing variables/functions/constants.

Creating a context

• Type: function createContext(options?: Partial<ContextOptions>): ContextAPI

Use createContext to manage isolated or persistent variable scopes:

import { createContext } from "@mathflowjs/mathflow";

const ctx = createContext({
	// ...
});

preferences

You can set preferences when creating a context, or update them at any time.

const ctx = createContext({
	preferences: {
		// key: value
	},
});

type Preferences = {
	angles: "rad" | "deg";
	fractionDigits: number;
	precision: number;
};

angles

• Type: rad - radians | deg - degrees
• Default: rad

Mode of angles - trignometric functions depend on angles to handle arguments and return values.

const ctx = createContext({
	preferences: {
		angles: "deg",
	},
});

// or

ctx.preferences.angles = "deg";

// example: sin(30) = 0.5 in degrees mode

fractionDigits

• Type: number
• Default: 15

Number of digits after the decimal point. Must be in the range 0 - 20, inclusive.

const ctx = createContext({
	preferences: {
		fractionDigits: 10,
	},
});

// or

ctx.preferences.fractionDigits = 10;

precision

• Type: number
• Default: 15

Number of significant digits. Must be in the range 1 - 21, inclusive.

const ctx = createContext({
	preferences: {
		precision: 20,
	},
});

// or

ctx.preferences.precision = 20;

variables

You can provide predefined variables and constants to the context at its creation:

• Type: Record<string, number>

const ctx = createContext({
	variables: {
		x: 1,
	},
	constants: {
		g: 9.81,
	},
});

For an existing context, use:

• Type: Map<string, number>

ctx.variables.set("x", 1);

ctx.constants.set("g", 9.81);

Managing variables using:

// Check if variable exists
ctx.variables.has("x"); // true/false

// Get variable value
ctx.variables.get("x"); // Returns value

// Set variable value
ctx.variables.set("x", 10);

// Delete variable
ctx.variables.delete("x");

// Clear all variables
ctx.variables.clear();

functions

Add custom functions to a context.

• Type: (...args: number[]) => number

const ctx = createContext({
	functions: {
		double: (x) => 2 * x,
	},
});

For an existing context, use:

• Type: Map<string, number>

ctx.functions.set("double", (x) => 2 * x);

Solving expressions

solve

Evaluate a single mathematical expression string

• Type: (code: string) => ({ value: number, solution: string[] })

ctx.solve("1 + 3 + 5");
// { value: 9, solution: ['4 + 5', '9'] }

solveBatch

Evaluate multiple mathematical expressions at once

• Type: (code: string) => ({ value: number, solution: string[] }[])

ctx.solveBatch(`x=2\ny=3x\nz=x+y`);
// [
//   { value: 2, solution: ['x = 2'] },
//   { value: 6, solution: ['y = 3 * 2', 'y = 6'] },
//   { value: 8, solution: ['z = 2 + 6', 'z = 8'] },
// ]