Is there a way to remove a particular value from an array?

Question

I have an array/list that has 8 values. I want to randomly choose a value, assign it to a variable and then remove that value from the array so that only 7 values left. how do I do this?

Answer 1

1) create a function to get random number in a given range first (this will be used to get a random index)
2) next we will select random index
3) save the value to temp variable
4) remove the value from the array using splice method

function randVal(min, max) {
return Math.floor(Math.random()*(max - min + 1) + min);
}

arr = [1,2,3,4,5,6,7,8];
ind = randVal(0, arr.length-1);
temp = arr[ind];
arr.splice(ind, 1);

Answer 2

The splice method return an array with the items removed, so you can shorten the two last lines of @Burey code:

temp = arr.splice(ind, 1)[0];

Answer 3

nice one visph :]

Answer 4

The number of items of an array is defined in the array.length attribute ^^

Answer 5

if i send 0 and arr.length-1 in the first iteration (arr.length === 8)

i get the following

Math.floor(Math.random()*(7-0+1)+0);

Math.random is in the range of [0.0, 1.0) (1.0 not included)

so let's say i get 0.88 from Math.random()

so 0.88 * (7-0+1) + 0 is actually 0.88 * 8 == 7.04

floor(7.04) that and what you get?

7, which is the last index in the array at that given moment :)

of course any value above 0.88 will also produce tbe same outcome in this scenario

and even some values velow

Answer 6

omg
SoloLearn lottery

best
idea
ever

xD

Answer 7

wither way
the inside of the brackets is evaluated before

Answer 8

@Burey, If I am reading the code above correctly it means it can never choose the last value in an array. As in, if I have 8 values in the array, by adding that 1 in the brackets the highest possible value of the bracketed result is 7 and coupled by the fact that math.floor is not inclusive of 1 my random selection will never choose the index value 7 which is the 8th value in an array of length 8. No?

Answer 9

@Burey, --> so 0.88 * (7-0+1) + 0 is actually 0.88 * 8 == 7.04

I thought the order of operations follows that addition is done first so it is evaluated as '0.88*6 ==5.28. I had ignored the rule regarding Associativity and that Subtraction and Addition are the same level of order and are evaluated left to right whichever comes first.

Answer 10

Visph, thanks!

Answer 11

you can use delete example
in the following array
var days=["Sun","Mon","Tue"];
you can remove a particular day like
delete days[1];
and a particular value will be removed