# from green to red color depend on percentage

I have a poll system and I want answers for this poll to be colored. For example: If it’s 10% it would be red, if 40% it would be yellow and if 80% it would be green, so I want my javascript code to use the rgb colors to make a color according to the given percentage.

```function hexFromRGB(r, g, b) {
var hex = [
r.toString( 16 ),
g.toString( 16 ),
b.toString( 16 )
];
\$.each( hex, function( nr, val ) {
if ( val.length === 1 ) {
hex[ nr ] = "0" + val;
}
});
return hex.join( "" ).toUpperCase();
}
```

Now I want hex from percent.

This may be more than you need, but this lets you set up any arbitrary color map:

```var percentColors = [
{ pct: 0.0, color: { r: 0xff, g: 0x00, b: 0 } },
{ pct: 0.5, color: { r: 0xff, g: 0xff, b: 0 } },
{ pct: 1.0, color: { r: 0x00, g: 0xff, b: 0 } } ];

var getColorForPercentage = function(pct) {
for (var i = 1; i < percentColors.length - 1; i++) {
if (pct < percentColors[i].pct) {
break;
}
}
var lower = percentColors[i - 1];
var upper = percentColors[i];
var range = upper.pct - lower.pct;
var rangePct = (pct - lower.pct) / range;
var pctLower = 1 - rangePct;
var pctUpper = rangePct;
var color = {
r: Math.floor(lower.color.r * pctLower + upper.color.r * pctUpper),
g: Math.floor(lower.color.g * pctLower + upper.color.g * pctUpper),
b: Math.floor(lower.color.b * pctLower + upper.color.b * pctUpper)
};
return 'rgb(' + [color.r, color.g, color.b].join(',') + ')';
// or output as hex if preferred
};
```
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