Rounding decimals in Sass

_decimal.scss

// _decimal.scss | MIT License | gist.github.com/terkel/4373420

// Round a number to specified digits.
//
// @param  {Number} $number A number to round
// @param  {Number} [$digits:0] Digits to output
// @param  {String} [$mode:round] (round|ceil|floor) How to round a number
// @return {Number} A rounded number
// @example
//     decimal-round(0.333)    => 0
//     decimal-round(0.333, 1) => 0.3
//     decimal-round(0.333, 2) => 0.33
//     decimal-round(0.666)    => 1
//     decimal-round(0.666, 1) => 0.7
//     decimal-round(0.666, 2) => 0.67
//
@function decimal-round ($number, $digits: 0, $mode: round) {
    $n: 1;
    // $number must be a number
    @if type-of($number) != number {
        @warn '#{ $number } is not a number.';
        @return $number;
    }
    // $digits must be a unitless number
    @if type-of($digits) != number {
        @warn '#{ $digits } is not a number.';
        @return $number;
    } @else if not unitless($digits) {
        @warn '#{ $digits } has a unit.';
        @return $number;
    }
    @for $i from 1 through $digits {
        $n: $n * 10;
    }
    @if $mode == round {
        @return round($number * $n) / $n;
    } @else if $mode == ceil {
        @return ceil($number * $n) / $n;
    } @else if $mode == floor {
        @return floor($number * $n) / $n;
    } @else {
        @warn '#{ $mode } is undefined keyword.';
        @return $number;
    }
}

// Ceil a number to specified digits.
//
// @param  {Number} $number A number to round
// @param  {Number} [$digits:0] Digits to output
// @return {Number} A ceiled number
// @example
//     decimal-ceil(0.333)    => 1
//     decimal-ceil(0.333, 1) => 0.4
//     decimal-ceil(0.333, 2) => 0.34
//     decimal-ceil(0.666)    => 1
//     decimal-ceil(0.666, 1) => 0.7
//     decimal-ceil(0.666, 2) => 0.67
//
@function decimal-ceil ($number, $digits: 0) {
    @return decimal-round($number, $digits, ceil);
}

// Floor a number to specified digits.
//
// @param  {Number} $number A number to round
// @param  {Number} [$digits:0] Digits to output
// @return {Number} A floored number
// @example
//     decimal-floor(0.333)    => 0
//     decimal-floor(0.333, 1) => 0.3
//     decimal-floor(0.333, 2) => 0.33
//     decimal-floor(0.666)    => 0
//     decimal-floor(0.666, 1) => 0.6
//     decimal-floor(0.666, 2) => 0.66
//
@function decimal-floor ($number, $digits: 0) {
    @return decimal-round($number, $digits, floor);
}

dart-sass deprecating use of / for division

fix:

// import at top of file
@use "sass:math";

Replacements

@return round($number * $n) / $n;

with

@return math.div(math.round($number * $n), $n);

@return ceil($number * $n) / $n;

with

@return math.div(math.ceil($number * $n), $n);

@return floor($number * $n) / $n;

with

@return math.div(math.floor($number * $n), $n);

Is there a way to round decimal points in this example?

//
// Aspect ratio
//
// Example:
//
// 16:9 aspect ratio, use:
//
// .element {
// 	@include aspectRatio(16, 9);
// }
//
// 4:3 aspect ratio, use:
//
// .element {
// 	@include aspectRatio(4, 3);
// }
//

@use "sass:math";

@mixin aspectRatio($width, $height) {
	position: relative;

	&:before {
		display: block;
		content: "";
		padding-top: math.div($height, $width) * 100%;
		width: 100%;
	}

	> * {
		position: absolute;
		top: 0;
		bottom: 0;
		left: 0;
		width: 100%;
		height: 100%;
		border: 0;
	}
}

For a 16/9 aspect ratio, I am getting 56.25% - would be nice to round that down to 56% if possible.

Version with the lastest sass dartsass requirements with @use and builtins math/meta :

@use "sass:math";
@use "sass:meta";

@function round($number, $digits: 0, $mode: round) {
  $n: 1;
  // $number must be a number
  @if meta.type-of($number) != number {
    @warn '#{ $number } is not a number.';
    @return $number;
  }
  // $digits must be a unitless number
  @if meta.type-of($digits) != number {
    @warn '#{ $digits } is not a number.';
    @return $number;
  } @else if not math.is-unitless($digits) {
    @warn '#{ $digits } has a unit.';
    @return $number;
  }
  @if $digits > 0 {
    @for $i from 1 through $digits {
      $n: $n * 10;
    }
  }
  @if $mode == round {
    @return math.div(math.round($number * $n), $n);
  } @else if $mode == ceil {
    @return math.div(math.ceil($number * $n), $n);
  } @else if $mode == floor {
    @return math.div(math.floor($number * $n), $n);
  } @else {
    @warn '#{ $mode } is undefined keyword.';
    @return $number;
  }
}