Multiline Axis Labels¶

Multiline axis labels allow better visualization of long categorical values. Instead of overcrowding the axis, labels can now be formatted across multiple lines, enhancing readability.

To create a multiline axis label, simply add "\n" inside the string where you want the line break.

In [1]:

import kotlin.random.Random

%useLatestDescriptors
%use dataframe
%use lets-plot

Quarters & Years¶

In [2]:

// Create a DataFrame with artificial income and expenses
val years = listOf(2022, 2023, 2024)
val quarters = listOf("Q1", "Q2", "Q3", "Q4")

val quarterYears = mutableListOf<String>()
val types = mutableListOf<String>()
val amounts = mutableListOf<Int>()

for (year in years) {
    val baseIncome = Random.nextInt(5000, 15000)
    val baseExpenses = baseIncome * Random.nextDouble(0.6, 0.9)
    
    for (quarter in quarters) {
        val income = baseIncome + Random.nextInt(-2000, 2000)
        val expenses = baseExpenses + Random.nextInt(-1500, 1500)
        val quarterYear = "$quarter-$year"
        
        quarterYears.add(quarterYear)
        types.add("Income")
        amounts.add(income.toInt())
        
        quarterYears.add(quarterYear)
        types.add("Expenses")
        amounts.add(expenses.toInt())
    }
}

val df = dataFrameOf("Quarter_Year" to quarterYears, "Type" to types, "Amount" to amounts)
df.head(4)

Out[2]:

DataFrame: rowsCount = 4, columnsCount = 3

Quarter_Year	Type	Amount
Q1-2022	Income	15425
Q1-2022	Expenses	7232
Q2-2022	Income	13012
Q2-2022	Expenses	8337

In [3]:

// Multiline labels for X-axis
val xLabelsMapping = years.flatMap { year ->
    quarters.map { quarter -> if (quarter == "Q1") "$quarter\n$year" else quarter }
}

In [4]:

letsPlot(df.toMap()) {
    x = "Quarter_Year"
    y = "Amount"
    color = "Type"
} +
    geomLine(size = 1.5) +
    geomPoint(size = 4.0) +
    scaleXDiscrete(labels = xLabelsMapping) +
    ggtitle("Quarterly Income vs Expenses") +
    xlab("Quarters") +
    ylab("Amount ($)") +
    theme(axisTextX = elementText(angle = 30))

Out[4]: