I designed this stuff as a Monkey Patch, but of course you can do it any way you want.
Okay. We have this given data array.
const data = [
{
"A" : 10,
"B" : 10,
"C" : "One",
},
{
"A" : 10,
"B" : 5,
"C" : "Two",
"D" : 6,
}
,
{
"A" : 10,
"B" : 5,
"C" : "Two",
"D" : 7,
}
,
{
"A" : 10,
"B" : 2,
"C" : "Three",
"D" : "unknown",
}
]
console.log("getUniqueValues: ",JSON.stringify(d3.getUniqueValues(data)));
// console: getUniqueValues: {"A":["10"],"B":["10","2","5"],"C":["One","Three","Two"],"D":["6","7","unknown"]}
console.log("subextent: ",JSON.stringify(d3.subextent("B",data)));
// console: subextent: [2,10]
console.log("subkeys: ",JSON.stringify(d3.subkeys(data)));
// console: subkeys: ["A","B","C","D"]
console.log("extentList: ",JSON.stringify(d3.extentList(data)));
// console: extentList: {"A":[10,10],"B":[2,10],"C":[null,null],"D":[6,7]}