# Formulas

Formulas use the values of the numeric Entries. That's to say, textual Entries are ignored in the computation, like struck ones.

**Card** → **Enable Formula**

After enabling the formula, notice the Card total and its output connector. This video uses an Auxiliary Root Card, but any kind of Card can have a Formula.

## Presets

**Card** → **Formula Presets**

To remove a preset, re-click the active preset button.

## Nested Cards are like parentheses

Deeper Cards compute before their parent(s).

Hypotenuse = (a^{2} + b^{2})^{½}

## Nested Card Operator

Like Entries, Nested Cards have an operator (unless they are the first Formula item).

## Operator Precedence

Formulas follow arithmetic rules: $1+2\times 3=7$

Exponentiation is right associative: $2^2^3=256$

## Alternatives to Formulas

The next document is about integrating JavaScript. Therefore, you can also write formulas like:

function ({ radius }) { return 2 * Math.PI * radius.value }