I'm creating a rating system, which rounds values to the nearest 0.5 and contains values between 0 and 5.
How can I iterate over an array, splitting a value (rounded to nearest 0.5), into units.
let rating = 3.7
let adjustedRating = (Math.round(rating * 2) / 2);
e.g. 3.7: ['1','1','1','1',0]
1.4 would equal ['1', '0.5', '0', '0', '0']
let starsToShow = new Array().fill('0');
starsToShow.forEach((v, i) => {
...
});
Do it using Array.from
let rating = 3.7
let adjustedRating = (Math.round(rating * 2) / 2);
console.log(
Array.from({
// set array length here
length: 5
}, function(_, i) { // iterate over element to update
// get the difference with index
var dif = adjustedRating - i;
// based on the difference assign the array value
return dif >= 1 ? '1' : dif > 0 ? '0.5' : '0';
})
);With simple for loop
var rating = 3.7,
res = [],
adjustedRating = (Math.round(rating * 2) / 2);
for (var i = 0; i < 5; i++) {
var dif = adjustedRating - i;
res.push(dif >= 1 ? '1' : dif > 0 ? '0.5' : '0');
}
console.log(res);
Array.from. Much less code than the one I suggested.
var dif = (Math.round(rating * 2) / 2) - i;Just another entry, using reduce and forEach. from is probably better if less code matters (1 line?), but compatibility may be an issue.
// Using forEach
function getRating0(rating) {
var stars = [0,0,0,0,0];
rating = Math.round(rating * 2) / 2;
stars.forEach(function(v, i) {
stars[i] = rating > 1? 1 : rating > 0? rating : 0;
--rating;
});
return stars;
}
// Using reduce
function getRating(rating) {
var stars = [0,0,0,0,0];
rating = Math.round(rating * 2) / 2;
return stars.reduce(function(acc, v, i) {
stars[i] = rating > 1? 1 : rating > 0? rating : 0;
--rating;
return stars;
}, stars);
}
console.log(getRating0(1.2));
console.log(getRating0(3.7));
console.log(getRating(1.2));
console.log(getRating(3.9));
$('.calculate-button').click(function(){
var rating = $('.rating').val();
var array = new Array();
while (rating > 0){
var currentRating;
if(rating > 1)
{
var currentRating = 1;
rating -= currentRating;
array.push(currentRating);
}
else{
var currentRating = (Math.round(rating * 2) / 2).toFixed(1);
rating = 0;
array.push(parseFloat(currentRating));
}
}
while (array.length < 5)
{
array.push(0);
}
console.log(array);
});<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text" class="rating"/>
<button class="calculate-button">Calculate</button>This could work as you wanted to, but I would prefer if you would take the suggestion of AlienHoboken. It's much cleaner.
let rating = 3.7;
let adjustedRating = (Math.round(rating * 2) / 2);
let tempRating = adjustedRating;
let starsToShow = new Array(5).fill(0);
for(let i=0; i<5; i++) {
if (tempRating > 0.5) {
tempRating -= 1.0;
starsToShow[i] += 1.0;
} else {
starsToShow[i]+= 0.5;
break;
}
}
console.log(starsToShow);
1.4 would equal ['1', '0.5', '0', '0', '0']1.4 should equal to that ?3.7should be['1','1','1','1',0]?