front-end-developer_1_

Front-End-Developer - Level 1
06.Methods
Embedded Video: https://www.youtube.com/watch?v=fBZvoT9WfMs?rel=0
Now that you've got the basics of numbers down, let's learn how to manipulate them a bit.
First, let's change a number into exponential notation.
If you're not familiar with exponential notation, here's how it works. Take the number 78.5. In
exponential notation, we write it 7.85 10. Or take 356.97; in exponential notation, that's
3.5697 102. You can also write it as 3.5697e+2.
Exponential notation makes it easy to write very large or very small numbers. For example,
1,000,000,000 becomes 1e+9, and 0.00000002 becomes 2e-8.
We can use JavaScript to easily change numbers into exponential notation:
>48432.78.toExponential();
"4.843278e+4"
toExponential() is called a method. You can think of a method as a message that you send
to a number, and the result that JavaScript gives you as the number's response to that
message.
You can also go in the other direction, and convert out of exponential notation:
>4.587e2.toFixed();
"459"
The toFixed() method will round to the nearest whole number. Here's how we can tell it
how many decimal places to use:
46.1.toFixed(2);
46.10
The 2 in the parentheses is an argument to the toFixed() method. Arguments provide a
bit more information to methods to help them know what they're supposed to do. In this
case, the argument is optional. When a method doesn't take an argument, or when the
argument is optional and you aren't using it, you still need the parentheses on the end - so
you have write 1.05e3.toFixed() , not 1.05e3.toFixed .
Methods
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