utils

Documentation

Overview

Package utils provides utility functions for the Charta graph system. This file specifically handles Braille character mapping for condensed graph mode.

Package utils provides utility functions for the Charta graph system.

This package contains helper functions used across multiple graph types:

• Mathematical operations: Sum, Average, Mod
• Scale calculations: GetMaxScale
• Type conversions: ToSliceOfAny
• Terminal detection: IsTrueColor
• Braille character mapping: GetBraille (in braille.go)

These utilities are designed to be lightweight and focused on specific tasks needed by the graph rendering system.

Index

• func Average(tab []float64) float64
• func GetBraille(l [4]float64) string
• func GetMaxScale(v float64) int
• func IsTrueColor() bool
• func Mod(a int, b int) int
• func Sum(tab []float64) float64
• func ToSliceOfAny[T any](s []T) []any

Functions

func Average

func Average(tab []float64) float64

Average calculates the arithmetic mean of a slice of float64 values. This is a utility function used by graph types that need to compute averages.

Parameters:

• tab: Slice of float64 values to average

Returns:

• avg: The arithmetic mean of the input values

func GetBraille

func GetBraille(l [4]float64) string

GetBraille returns the Braille character corresponding to the given array of values. This function is used in condensed graph mode to represent multiple data points within a single character position.

Parameters:

• l: Array of 4 float64 values representing normalized positions (-0.5 to 1)

Returns:

• string: The corresponding Braille Unicode character

Example:

• GetBraille([4]float64{0.5, 0.5, 0.5, 0.5}) returns "⡇"
• GetBraille([4]float64{1, 1, 1, 1}) returns "⣿"

func GetMaxScale

func GetMaxScale(v float64) int

GetMaxScale calculates an appropriate scale maximum for a given value. It determines a "nice" round number that is greater than the absolute value, using multiples of 2, 5, or 10 for better readability on graphs. The function preserves the sign of the input value.

Parameters:

• v: The value to calculate a scale for

Returns:

• int: A rounded scale value (2, 5, 10, 20, 50, 100, etc.) with appropriate sign

Example:

• GetMaxScale(75.0) returns 100
• GetMaxScale(-75.0) returns -100
• GetMaxScale(35.0) returns 50

func IsTrueColor

func IsTrueColor() bool

IsTrueColor checks if the terminal supports 24-bit true color. This is determined by checking the COLORTERM environment variable for "truecolor" or "24bit" values.

True color support enables:

• Smooth color gradients in heatmaps
• RGB color specifications
• Condensed mode with Braille characters

Returns:

• bool: true if the terminal supports 24-bit color, false otherwise

func Mod

func Mod(a int, b int) int

Mod calculates the modulo (remainder) of integer division. This function provides a custom modulo implementation that may handle edge cases differently than the built-in % operator.

Parameters:

• a: The dividend (number to be divided)
• b: The divisor (number to divide by)

Returns:

• int: The remainder of a divided by b

Example:

• Mod(10, 3) returns 1
• Mod(15, 5) returns 0
• Mod(7, 4) returns 3

func Sum

func Sum(tab []float64) float64

Sum calculates the sum of a slice of float64 values efficiently. This optimized version uses direct pointer access and avoids bounds checking where possible for better performance with large slices.

Parameters:

• tab: Slice of float64 values to sum

Returns:

• sum: The arithmetic sum of the input values

func ToSliceOfAny

func ToSliceOfAny[T any](s []T) []any

ToSliceOfAny converts a typed slice to a slice of any (interface{}). This is a generic utility function useful for working with functions that require []any parameters while maintaining type safety in the calling code.

Parameters:

• s: Slice of any type T to convert

Returns:

• []any: A new slice containing the same elements as interface{} values

Example:

• ToSliceOfAny([]int{1, 2, 3}) returns []any{1, 2, 3}
• ToSliceOfAny([]string{"a", "b"}) returns []any{"a", "b"}