%useLatestDescriptors
%use lets-plot

@file:DependsOn("org.apache.commons:commons-math3:3.6.1")

import kotlin.random.Random
import org.apache.commons.math3.distribution.MultivariateNormalDistribution

val cov : Array<DoubleArray> = arrayOf(doubleArrayOf(1.0, 0.0),
                                        doubleArrayOf(0.0, 1.0))
val means : DoubleArray = doubleArrayOf(0.0, 0.0)
val xy = MultivariateNormalDistribution(means, cov).sample(400)

val xs = xy.map { it[0] }
val ys = xy.map { it[1] }

val p = letsPlot() + ggsize(600,200)

val scatter = p + geomPoint(color="black", alpha=.4) {x=xs; y=ys}
scatter

val histogram = p + geomHistogram(fill="dark_magenta") {x=xs}
histogram

// Set scale X limits manually because of computed automatically
// the scale used by each plot would be slightly different
// and the stacked plots wouldn't be aligned.
val scale_x = scaleXContinuous(limits=-3.5 to 3.5)
GGBunch().addPlot(histogram + scale_x, 0, 0)
         .addPlot(scatter + scale_x, 0, 200)

val upper_theme = theme(axis="blank", axisText=elementText(), axisTitleY=elementText(), panelGridMajorY="blank")
val lower_theme = theme(axis="blank", axisTextY=elementText(), axisTitle=elementText())

GGBunch().addPlot(histogram + upper_theme + scale_x, 0, 0)
         .addPlot(scatter + lower_theme + scale_x, 0, 200)

GGBunch().addPlot(histogram + upper_theme + scale_x, 0, 0, 600, 100)
         .addPlot(scatter + lower_theme + scale_x, 0, 100, 600, 300)