notebookVariable = 10
hellostatement = {
var firstPart = "hello" // can change the value
const secondPart = ", world" // constant, cannot be changed
return firstPart + secondPart
}
hellostatement
intVariable = 10
typeof(intVariable)
floatVariable = 3.14
typeof(floatVariable)
stringVariable = "hello, everyone!"
typeof(stringVariable)
booleanVariable = true
typeof(booleanVariable)
listVariable = []
typeof(listVariable)
Array.isArray(listVariable)
dictionaryVariable = ({"color":"red"})
typeof(dictionaryVariable)
Array.isArray(dictionaryVariable)
{
var insideDictionary = {}
return typeof(insideDictionary)
}
{
var value = 1;
if (1) { value = 2; }
else { value = 0; }
return value
}
{
var value = 1;
if (1) { value = 2; }
else { value = 0; }
return value
}
{
var value = 1;
if (0) { value = 2; }
else { value = 0; }
return value
}
{
var value = 1;
if (0) { value = 2; }
else if (false) { value = 3; }
else { value = 0; }
return value
}
{
var numbers = []
for (var i = 0; i < 10; i++) {
numbers.push(i)
}
return numbers
}
setOfNumbers0to9 = d3.range(10)
{
var numbers = []
for (var i = 0; i < setOfNumbers0to9.length; i++) {
numbers.push(setOfNumbers0to9[i]*1)
}
return numbers
}
{
var dictionaryOfValues = {}
for (var i = 0; i < 10; i++) {
dictionaryOfValues["index_"+i] = i
}
return dictionaryOfValues
}
{
var dictionaryOfValues = {}
for (var i = 0; i < 10; i++) {
dictionaryOfValues["index_"+i] = i
}
var numbers = []
for (var j in dictionaryOfValues) {
numbers.push({"value":dictionaryOfValues[j]})
}
return numbers
}
exampleData1 = d3.range(7).map(function(d,i) { return { "index":i,"value":d,"valueX10":d*10 } })
exampleData1[3]["valueX10"]
exampleData2 = d3.range(7).map((d,i)=> ({ "index":i,"value":d,"valueX10":d*10 }) )
filteredData = exampleData2.filter((d,i)=> ((d.value+1)%2) )
startingCSV = FileAttachment("co-est2019-alldata.csv").text()
parsedData = d3.csvParse(startingCSV).map((d,i)=> ({state:d.STNAME,city:d.CTYNAME,pop:d.POPESTIMATE2019}))
md`
AND == &&
OR == ||`
PA = parsedData.filter((d,i)=> d.state=="Pennsylvania" && d.city!=d.state)
{
var population = 0
for (var i = 0; i < PA.length; i++) {
population = population + parseInt(PA[i].pop)
}
return population
}
d3 = require('d3')
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