a double is 64 bits

10011011 10011011 10011011 1011011
10011011 10011011 10011011 1011011

(the first digit is the sign, the next 11 digits are the exponent, the rest is the fraction)

± 2 ^ E - 1023 x 1.frac

That means there are 2^64 doubles.

The biggest one is about 2^1023

weird double arithmetic

2^52 + 0.2 = 2^52 (the next number after 2^52 is 2^52 + 1)

doubles get farther apart as they get bigger

betweeen 2^n and 2^n+1 there are always 2^52 doubles, evenly spaced

that means that the next double after 2^60 is 2^60 =64 (2^60 / 2^52)

Javascript only has doubles (no integers!)

2**53 9007199254740992

2**53+1 9007199254740992 (same number! uh oh!)

panel 5

person with short spiky hair, baffled: doubles are scary and their arithmetic is weird!

person with short curly hair, calm and reassuring: they’re very logical! just understand how they work and don’t use integers over 2^53 in Javascript <3