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"cell_type": "code",
"execution_count": 1,
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"outputs": [
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" \n",
" "
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"metadata": {},
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"source": [
"%useLatestDescriptors\n",
"%use lets-plot\n",
"\n",
"import kotlin.math.*"
]
},
{
"cell_type": "code",
"execution_count": 2,
"metadata": {},
"outputs": [],
"source": [
"// This example was found at: \n",
"// https://jakevdp.github.io/PythonDataScienceHandbook/04.04-density-and-contour-plots.html\n",
"\n",
"fun meshgridPoints(x:List, y:List):List> {\n",
" val xSer = y.flatMap { x }\n",
" var yInd = -1\n",
" val ySer = y.flatMap { \n",
" yInd++\n",
" List(x.size) {y[yInd]} \n",
" }\n",
" return xSer.zip(ySer)\n",
"}\n",
"\n",
"val gridPoints = meshgridPoints(\n",
" generateSequence(0.0, {it + 6.0/50} ).takeWhile { it <= 5.0 }.toList(),\n",
" generateSequence(0.0, {it + 6.0/40} ).takeWhile { it <= 5.0 }.toList())\n"
]
},
{
"cell_type": "code",
"execution_count": 3,
"metadata": {},
"outputs": [],
"source": [
"fun f(x:Double, y:Double): Double {\n",
" return sin(x).pow(10) + cos(10 + y * x) * cos(x)\n",
"}\n",
"\n",
"val X = gridPoints.map { it.first }\n",
"val Y = gridPoints.map { it.second }\n",
"val Z = gridPoints.map { f(it.first, it.second) }"
]
},
{
"cell_type": "code",
"execution_count": 4,
"metadata": {},
"outputs": [
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"data": {
"text/html": [
" \n",
" "
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"execution_count": 4,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"val p = letsPlot {x=X; y=Y; fill=Z}\n",
"p + geomTile() + scaleFillHue()"
]
},
{
"cell_type": "code",
"execution_count": 5,
"metadata": {},
"outputs": [
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"text/html": [
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"execution_count": 5,
"metadata": {},
"output_type": "execute_result"
}
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"source": [
"// Lets use greyscale and also remove colorbar.\n",
"val p1 = p + geomTile(alpha=.5) + scaleFillGrey(1, .2, guide=\"none\")\n",
"p1"
]
},
{
"cell_type": "code",
"execution_count": 6,
"metadata": {},
"outputs": [
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"data": {
"text/html": [
" \n",
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"execution_count": 6,
"metadata": {},
"output_type": "execute_result"
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"source": [
"// Add contours\n",
"p1 + geomContour(color=\"red\") {z=Z}"
]
},
{
"cell_type": "code",
"execution_count": 7,
"metadata": {},
"outputs": [
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"data": {
"text/html": [
" \n",
" "
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"execution_count": 7,
"metadata": {},
"output_type": "execute_result"
}
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"source": [
"// Set contour color by level\n",
"p1 + geomContour {z=Z; color=\"..level..\"} + scaleColorGradient(low=\"dark_green\", high=\"yellow\")"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"### Filling contours by level"
]
},
{
"cell_type": "code",
"execution_count": 8,
"metadata": {},
"outputs": [
{
"data": {
"text/html": [
" \n",
" "
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"execution_count": 8,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"val p2 = letsPlot {x=X; y=Y}\n",
"\n",
"// Filled polygons are not working very well in this case\n",
"p2 + geomPolygon(stat=Stat.contour {z=Z}) {fill=\"..level..\"}"
]
},
{
"cell_type": "code",
"execution_count": 9,
"metadata": {},
"outputs": [
{
"data": {
"text/html": [
" \n",
" "
]
},
"execution_count": 9,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"// 'contourf' geom works a lot better:\n",
"p2 + geomContourFilled {z=Z; fill=\"..level..\"}"
]
}
],
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"display_name": "Kotlin",
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