{
const selectRegion = vl
.selectPoint("SelectionMenu")
.fields("REGION")
.init(RegionCategories[0])
.bind(vl.menu(RegionCategories).name("Pick City Name: "));
const filterPrecipitation = vl
.param("CountValue")
.value(0)
.bind(vl.slider(0, 20000, 10).name("Filter precipitation: "));
const show = vl.and(selectRegion, "datum.CountValue >= CountValue");
return vl
.markLine()
.data(CrimeCodeAreaData)
.params(selectRegion, filterPrecipitation)
.encode(
vl.x().fieldT("Year"),
vl.y().fieldQ("Count"),
vl.color().if(show, vl.fieldN("REGION")).value("grey"),
vl.tooltip(["date", "Year", "Count"]),
vl.opacity().if(show, vl.value(0.9)).value(0.5)
)
.width(600)
.height(500)
.render();
}