Play the numbers in JavaScript and turn your eyes upside down

1. There are some wonderful phenomena in the figures in JavaScript.

You can do your own experiment in the Chrome console:

1 = = = 1.0; True

Accustomed to the strong type of language, such as JAVA,C,OC see this conclusion is still a little confused. This is because within JavaScript, all numbers are stored as 64-bit floating-point number, including positive. It complies with the IEEE 754 standard.

Look again, the calculation of floating-point numbers.

0.1 + 0.2;

Floating point number

Found that 0.3-0.2 is not equal to 0.2-0.1. So be careful when doing floating-point calculations and comparisons.

For integer operations, JavaScript only supports 32-bit

Play the numbers in JavaScript and turn your eyes upside down