# Gaia/Calculator

From MozillaWiki

< Gaia

## Contents

## Design Specs

#### Interaction

#### Visual

## Requirements

#### General

- I can see the equation I've entered
- I can see the results of the current calculation

#### Basic Operations & Calculator functions

- I can enter in a number with a maximum of N digits
- I can change the sign of a number
- I can enter in a decimal number
- I can add two numbers together
- I can subtract one number from the other
- I can multiply two numbers together
- I can divide a non-zero number from another number
- I can clear an equation from the screen
- I can clear the last digit of a number I just entered, as long as I haven't pressed an operator key yet

#### Extended Calculator functions (Might not need or want these features for v1)

- I can perform an operation a second time by pressing the equals sign a second time.
- I can convert the result from a percentage to a decimal value.
- I can store a result in the calculator's memory
- I can retrieve a result from the calculator's memory
- I can clear the value in the calculator's memory
- log/ln/e
- ^
- squareroot and root
- Pi/tau
- cos/sin/tan

#### Computation Cases

- I'm informed that I can't divide a number by zero (cannot divide by zero)
- I'm informed that I can't divide zero by zero (result is undefined)
- I can view the result in exponential notation if the number is too large or too small to be displayed