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JavaScript

Posted by brandonlind2
brandonlind2
7,823 Points

any idea as to why this random word function isnt working?

The randomWord function keeps returning undefined for some reason

var words=[
'car',
'dog',
'mouse',
'hotel',
'car'];

function randomWord(list){
    var random_num= Math.floor(Math.random() * list.length) +1;
    var word=list[random_num];
    return word
}

randomWord(words)

1 Answer

Travis Flatt
Travis Flatt
20,149 Points

It sorta does. The Math bits are throwing you out of range occasionally, so there'll be an undefined here and there. 

var words=[
'car',
'dog',
'mouse',
'hotel',
'car'];

function randomWord(list){

    var word=list[Math.floor(Math.random()*list.length)];
    console.log(word);
}

randomWord(words);

That +1 in the original is what you'd want to use if you were looking for a non-zero random number, but you're using it for an array index, which is zero-based (So, you'll occasionally get that undefined when the result is higher than the available indices go).