Overview

Cl Calc is an open-source, lightweight, command-line style online calculator. While it has clean and simple interface, it can perform some advanced calculations because it is based on powerful MathJS library.

Some of the Cl Calc features include:

• Arbitrary precision (long arithmetic) math expression evaluation.
• Variety of built-in mathematical, scientific, programming and utility functions. This includes algebra, arithmetic, combinatorics, probability, matrix, statistics, trigonometry, logical, encoding functions and more.
• User defined variables and functions.
• Many built-in datatypes, including complex numbers, fractions, vectors, matrices and colors.
• Base64 Encoding, Unicode, hexadecimal, octal and binary numbers support.
• Persistent links to store or share your calculations.
• Pretty-printing expressions with TeX.
• Simple 2d functions plotting.

Cl Calc is written purely in JavaScript and it evaluates all expressions directly in your browser. This means that your data is never sent to the server for processing or storage. Cl Calc can be installed as a progressive web application (PWA) and can work fully offline.

Cl Calc is completely open-source (source is available on GitHub) and licensed under MIT license. It is hosted in transparent manner through GitHub Pages.

DISCLAIMER: Since Cl Calc uses floating-point arithmetic rounding errors and other errors that lead to precision loss are inevitable. Never use Cl Calc for scientific, financial and any other calculations that need precise results. Also remember that as any software product Cl Calc and libraries it uses may have bugs and may produce incorrect results. Always double-check your calculations using multiple tools.

Quick Start

Simply type an expression and hit enter to calculate the result:

You can use some of the built-in constants:

or you can define your own:

You can also use some of the built-in functions:

or define your own as well

You can work with vectors (aka lists):

matrices:

units:

colors:

and much more!

To get general help inside the calculator you can use help command:

Or to get help on a specific function or constant you can use help as a function with one argument, for example:

User Interface

Cl Calc user interface is designed to resemble the interface of a traditional UNIX terminal. You type expression or command into the command line and press Enter key to evaluate it.

Terminal

Terminal user interface is based on jQuery Terminal library. It supports a variety of key combinations that are described in the documentation section. Below is a brief overview of these key combinations:

Persistent Links

If you need to save your Cl Calc session for later use, or to share it with someone else you can click create link button () in the top left corner of the window. It will open a pop-up with the generated link that you can copy. If you open this link later, the whole content of your Cl Calc window will be restored.

Alternatively, you can create link that will only contain a single command from Cl Calc, by clicking on corresponding create expression link button () on the right side of the window. When you open this link, it will only restore its command and not the whole command log.

Please note that since Cl Calc doesn't store or send your commands to the server, all information required to restore your session is encoded directly in the link itself. This means that these links can get quite long.

Pretty Printing

You can view "pretty-printed" version of your calculations logs by clicking on the Toggle TeX Panel button (). Pretty-printing can be especially useful if you work with matrices or vectors as they will be displayed in more recognizable form compared to what terminal displays.

Settings

Cl Calc settings are configured through the settings dialog which can be accessed by pressing () button. Settings are saved in the browser local storage. The available settings are: output number format, thousands separator, precision and color theme.

The output number format setting sets the base and the format for all numbers in the result of a calculation:

• "Decimal: Fixed": decimal base, fixed number format. Example: 123.4. This is the default value.
• "Decimal: Exponential": decimal base, exponential number format. Example: 1.234e+2.
• "Decimal: Engineering": decimal base, engineering number format - always have exponential notation, and select the exponent to be a multiple of 3. Example: 123.4e+6.
• "Decimal: Auto": decimal base, auto number format - switch between fixed and exponential notation automatically, based on the value.
• "Hexadecimal: Fixed": hexadecimal base, fixed number format. Example: 0x123.A.
• "Octal: Fixed": octal base, fixed number format. Example: 0o123.4.
• "Binary: Fixed": binary base, fixed number format. Example: 0b101.1.

Enabling thousands separator will group digits in thousands (i.e. by three digits) and use empty space as a delimiter. Selection and copying behavior is unchanged, so the delimiters won't be copied into the clipboard. Thousands separator only supported for default "Decimal: Fixed" number format.

Precision setting allows to configure maximum number of significant digits for calculations using big numbers. It can be set in a range of 8 - 4096. Be careful with using high precision as it may decrease responsiveness of Cl Calc. See Precision for more information about precision.

Color theme can be changed by selecting Light (default) or Dark color theme in the settings dialog.

MathJS Overview

Cl Calc uses MathJS library for expression parsing and evaluation. It is an extensive math library for JavaScript with a rich set of features and active community. Since Cl Calc only extends MathJS with some additional features, everything that is available in MathJS is available in Cl Calc.

You can find exhaustive MathJS Documentation and Examples on the MathJS website. Below is just a brief overview of its main features.

Data Types

The data types suported by MathJS are:

Number/BigNumber:

Complex:

Fraction:

Boolean:

String:

Array (vector):

Matrix:

Unit:

Built-In Constants

Below are some of the built-in constants. For the complete list please refer to MathJS Documentation.

Built-In Functions

Below are some of the more common built-in functions. For the complete list please refer to MathJS Documentation.

Operators

Below are some of the MathJS operators, for the complete list please see MathJS Documentation.

Variables

Variables can be defined using assignment operator and used in the same way as constants:

Variable value can also be changed using the assignment operator:

Please note that inside a function, function arguments take precedence over global variables:

Functions

Functions can be defined using following format:

where

• name is the name of the function
• arg1, arg2, ..., argN are the function arguments
• body is an expression used to calculate the result of the function for given arguments

For example:

All global variables (including user-defined variables), functions and constants can be accessed in the function body:

Help

You can use built-in function help(...) to get information about built-in functions and constants. For examply, try:

Linear Interpolation

To calculate linear interpolation between two values (a, b) for a parameter (t) in the closed unit interval [0, 1] you can use lerp(...) function:

Resulting value is calculated as

a, b - can be numbers or colors, while t must always be a number:

Please note that ARGB representation is used for colors interpolation. If this is not desirable, you can define your own color interpolation based on HSV or HSL color representation. Please refer to Colors section for more information.

Hex/Bin/Oct Numbers

Cl Calc supports hexadecimal, octal and binary numeric literals and provides functions to convert numbers to/from these representations.

Hexadecimal literals are prefixed with '0x', octal literal are prefixed with '0o' and binary literals are prefixed with '0b'. The literals can include decimal point. On evaluation hex and binary literals are automatically converted to decimal numbers. For example:

To convert numbers to hexadecimal, octal or binary representation use hex(...), oct(...) and bin(...) functions respectively.

By default, hexadecimal, octal and binary numbers maintain the same precision as regular numbers (i.e. they are BigNumbers as well):

To restrict hexadecimal, octal or binary literal to a specific signed (2's complement) integer and a specific word size append i suffix and a desired word size in bits.

To covert a decimal number to hexadecimal, octal or binary representation as a signed integer with a given word size use a second parameter with the desired word size (in bits) to hex, oct and bin functions.

Unicode

Cl Calc provides a few functions to work with Unicode encoding.

To convert a string to list of Unicode code points corresponding to each character use toCodePoints(...) function:

To convert back from code points list to string use fromCodePoints(...) function:

Similarly, to convert a string to UTF8 you can use toUtf8(...) function:

To convert from UTF8 to string use fromUtf8(...) function:

Base64 Encoding

To encode array of bytes to string using Base64 Encoding use base64Encode(...) function:

To decode Base64 encoded string back to byte array use base64Decode(...) function:

You can encode string to Base64 by encoding it to UTF8 first:

Hash Functions

Cl Calc supports the following hash functions: md5, sha1, sha224, sha256. Each hash function accepts an array of bytes as its argument and produces hash string as the result. Below are some examples:

Colors

Cl Calc supports some operations with colors by introducing Color data type, color literals and some functions that work with colors.

There are few ways to construct a Color. The easiest one is to use color literals. Color literals resemble web color format, where literal starts with hash character '#' followed by three bytes in hex representing RGB components, or four bytes in hex representing ARGB components (where A is an alpha component). If RGB format is used, alpha component is set to 255 (i.e. opaque). For example:

As you may notice, when Cl Calc outputs color as a result of an expression, it is displayed as a color preview square. You can click it to see color value. Checkerboard background used to preview opacity.

You can also construct color explicitly by calling any of the following functions:

You can add, subtract, divide and multiply colors in the same way as regular numbers. For these operations ARGB representation is used, and operation performed on each component individually:

You can also multiply and divide colors by a number:

You can convert color to different representations using following functions:

Function Plot

Cl Calc can plot a two-dimensional graph of a function with plot2d(...) function.

where

• expression an expression of a function to plot
• variable variable name that will be used as an 'x' variable (horizontal axis)
• from, to numbers representing begin and end of the interval that will be plotted

For example:

You can zoom function graph with a mouse wheel and drag it by holding left mouse button.

Please note that in its current implementation plot2d function doesn't detect vertical asymptotes. If you are plotting function that has vertical asymptotes you may see vertical lines appear where the function value "jumps".

Precision

Cl Calc is configured to use big numbers when possible with the default precision of 64 significant digits (you can read more about underlying long arithmetics library on Decimal.js GitHub Page). The precision can be adjusted in Settings.

While most of the MathJS functions and operators support big numbers, there are still some that don't and will degrade precision to 64-bit floating-point numbers. For example, complex numbers do not support long arithmetics and will degrade precision:

Aliases

For convenience, Cl Calc introduces some function aliases to built-in MathJS functions:

Last Evaluated Expression

For convenience, Cl Calc stores a reference to the result of the last evaluated expression in a special built-in variable '$'. It can then be used in the same manner as a regular variable.

While it can be useful for simple calculations, the '$' variable should be avoided in more complex calculations and especially calculations with statements. Because it holds a reference to the last result and not a copy of the result, it can observe the modifications to the value, which may sometimes appear unexpected:

About

Cl Calc is licensed under MIT license and its source code is available on the GitHub.

For contributing, reporting bugs or suggesting features please visit issues page.

Third party libraries:

• MathJS 10.1.0
• jquery.terminal 2.17.6
• KaTeX 0.12.0
• jQuery 3.5.1
• Bootstrap 3.4.1
• jquery-mousewheel 3.1.13