Sass functions to calculate the line height based off the font size, the content's width in px, and the golden ratio

golden-ratio-typography.sass

/**
 * Calculates the line height based on font size and the content's width in px. Based
 * off the research underlying Pearsonified's Golden Ratio Typography Calculator
 * https://pearsonified.com/typography/
 
 * Ex:	$font-size:		16px;
 *		$content-width:	1336px;
 *		$line-height:	calculate-line-height( $font-size, $content-width );
 *
 * @since	1.0.0
 *
 * @param	int		$font-size		The font size
 * @param	int		$content-width		The width of the content area
 * @param	int		$ratio			The ratio. Default 1.61803398875 (golden ratio)
 *
 * @return	int					The calculated line height
 */
@function calculate-line-height( $font-size, $content-width, $ratio: 1.61803398875 ) {
	$font-size: strip-unit( $font-size );
	$content-width: strip-unit( $content-width );
		
	@return $ratio - ( ( 1 / ( 2 * $ratio ) ) * ( 1 - ( $content-width / ( pow( ( $font-size * $ratio ), 2 ) ) ) ) );
}

/**
 * Calculates numbers to the mathmatical power (exponent)
 *
 * @since	1.0.0
 *
 * @param	int		$number		The number to increase
 * @param	int		$exponent	The power to increase the number by
 *
 * @return	int				The new number
 */
@function pow( $number, $exponent ) {
	$value: 1;
	
	@if $exponent > 0 {
		@for $i from 1 through $exponent {
			$value: $value * $number;
		}
	}
	
	@return $value;
}

/**
 * Removes units from values for easier modification
 *
 * @since	1.0.0
 *
 * @param	int		$number		The number to strip units from
 *
 * @return	int				The number without the unit
 */
@function strip-unit( $number ) {
	@if type-of( $number ) == 'number' and not unitless( $number ) {
		@return $number / ( $number * 0 + 1 );
	}
	
	@return $number;
}