Quickstart

kalker Quickstart

Kalker is a calculator program with support for user-defined variables, functions, differentiation, integration, vectors, matrices, and more. Use this skill when you need to:

• Evaluate mathematical expressions with advanced features
• Perform differentiation and integration
• Work with vectors and matrices
• Define custom functions and variables
• Use different number bases (binary, octal, hexadecimal)
• Perform calculations with syntax highlighting

Installation

cargo install kalker
kalker --version

Also available via Homebrew: brew install kalker

Core Usage

Interactive Mode

kalker

Starts an interactive calculator session. Type expressions and press Enter to evaluate.

Evaluate Single Expression

kalker "2 + 2"

Load File with Predefined Functions

kalker -i physics.kalk

Loads a file containing predefined functions and constants before starting the interactive session.

Mathematical Features

Basic Operations

2 + 2
10 - 3
4 * 5
20 / 4

Functions

sin(pi/2)
cos(0)
tan(pi/4)
sqrt(16)
log(100)

Variables

x = 5
y = 10
x + y

User-Defined Functions

f(x) = x^2
f(5)

g(x, y) = x * y
g(3, 4)

Differentiation

f'(2)
sin'(-pi)

Integration

∫(0, pi, sin(x) dx)
∫(0, π, cos(x) dx)

Vectors

(1, 2, 3)
(1, 2, 3) + (4, 5, 6)

Matrices

[1, 2, 3; 4, 5, 6; 7, 8, 9]

Sum Function

sum(1, 3, 2n+1)

Equivalent to: 21+1 + 22+1 + 2*3+1 = 15

Piecewise Functions

f(x) = { f(x + 1) if x <= 1; x otherwise }

Press Enter before typing the final } to create a new line without submitting.

Number Bases

Binary

0b1101
1101_2

Octal

0o5.3

Hexadecimal

0xff

Special Features

Previous Result

ans

Access the value of the previously calculated expression.

Multiple Expressions

2 + 2; 3 + 3

Separate expressions with semicolons to write them on the same line.

Special-Symbol Completion

Type a function name and press Tab to convert to special symbols:

sqrt → √

Advanced Features

Root Finding

x^2 = 64

Uses Newton's method to find roots (estimation and limited to one root).

File Loading

Load files with predefined functions and constants:

kalker -i filename.kalk

Or within the interactive session:

load filename

Useful for domain-specific calculations (e.g., physics constants).

Examples

Physics Calculation

# Define variables
m = 10  # mass in kg
a = 9.8  # acceleration in m/s²

# Calculate force
F = m * a

Geometry

# Area of circle
r = 5
A = pi * r^2

# Volume of sphere
V = (4/3) * pi * r^3

Calculus

# Derivative
f(x) = x^3
f'(2)

# Integral
∫(0, 1, x^2 dx)

Tips

• Use ans to reference the previous result
• Press Tab after function names for special symbols
• Load domain-specific files for specialized calculations
• Use semicolons for multiple expressions on one line
• Supports ambiguous syntax (e.g., 2sin50 + 2xy)
• Available as CLI, mobile app (Android), and web interface (https://kalker.xyz)