Random number acquisition

Math.ceil (); // round up. 

Math.floor (); // rounded down. 

Math.round (); // rounding. 

Math.random (); a pseudo-random number between 1.0 ~ //0.0. [1] contains 0 // do not contain such 0.8647578968666494 

Math.ceil (Math.random () * 10); // Get random integer from 1 to 10, 0 probability is extremely small. 

Math.round (Math.random ()); // Get equalizes random integer 0 to 1. 

Math.floor (Math.random () * 10) ; // be balanced to obtain random integer from 0 to 9. 

Math.round (Math.random () * 10) ; // Get substantially balanced random integer from 0 to 10, wherein the probability of obtaining a minimum value of 0 and a maximum 10 less than half. 
Because the result is 0 to 0.4 1.4 to 0,0.5 to 1,8.5 to 9,9.5 to 9.4 to 9.9 to 10. So only half of other digital distribution range of head and tail. 

Gets a random number:

getRandom function () { 
    return Math.round (Math.random () * 10) 
} 
the console.log (getRandom ()) 

acquires a random number between two numbers:

getRandom function (min, max) { 
    return Math.random () * (max-min) + min; 
} 
the console.log (getRandom (l, 5)) 

to obtain random integer between the two numbers (including the minimum free maximum):

getRandomInt function (min, max) { 
    min = Math.ceil (min) // ceil 
    max = Math.floor (max) // rounded down 
    return Math.floor (Math.random () * ( max-min )) + min // containing the maximum value, the minimum free 
} 
the console.log (getRandomInt (l, 5))

Acquiring random integer between the two numbers (also including a maximum minimum-containing):

getRandomIntInclusive function (min, max) { 
    min = Math.ceil (min); 
    max = Math.floor (max); 
    return Math.floor (Math.random () * (max - min +. 1)) + min; // containing maximum, containing minimum 
} 
the console.log (getRandomIntInclusive (l, 5));