{
console.log("Hello world");
// or
var helloMit = "Hello MIT";
console.log(helloMit);
}
height = 500
/*This is a
multiline
comment!*/
dimension = ({height, width})
width = 480
//dimension = {1000, 960}
// This block defines a cumulative sum of numbers from 0 to 10
{
let x = 0;
for (let i = 1; i <= 10; ++i) {
x += i;
}
return x;
}
x
function running_total(max) {
let x = 0;
for (let i = 1; i <= max; ++i)
x += i;
return x;
}
running_total(10)
{
const a = 5;
a = 6;
return a;
}
{
let a = 5;
a = 6
return a;
}
1 + 2
typeof (1 + 2)
1.0 + 2.5
typeof (1.0 + 2.5)
2 / 0
typeof (2 / 0)
"a" / 2
typeof ("a" / 2)
"hello, world"
typeof "hello, world"
"hello, " + "world"
name = "" // Fill your name in here!
`hello, world, it's ${name}`
//need the ` at start and end to make line appear
typeof (`hello, world, it's ${name}`)
9 > 10
typeof (9 > 10)
10 == 10
(9 > 10) && (10 == 10) // Evaluates to false AND true
(9 > 10) || (10 == 10) // Evaluates to false OR true
!(9 > 10) && (10 == 10) // Evaluates to NOT(false) AND true
!((9 > 10) || (10 == 10)) // Evaluates to NOT(false or true)
typeof (x)
{ let y
return typeof (y)
}
ra = ["one", 2, 3.0]
typeof ra
ra[0]
ra[3]
//arrays are on RAM and so inconvenient for longer items.
//Thus for longer items, we use Generators which just take out the elements of an array that we need.
function addthese(a, b) {
return a+b;
}
typeof(addthese)
typeof(addthese(1, 4))
{\}
"hello, world".toUpperCase()
directory = {
const data = {"employees":[
{"firstName":"John", "lastName":"Doe"},
{"firstName":"Anna", "lastName":"Smith"},
{"firstName":"Peter", "lastName":"Jones"}
]};
return data
}
directory_obj = ({
"employees":[
{"firstName":"John", "lastName":"Doe"},
{"firstName":"Anna", "lastName":"Smith"},
{"firstName":"Peter", "lastName":"Jones"}
]
})
directory.employees
directory.employees[1]
directory.employees[1].firstName
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
