Basic sass math functions

maths.scss

// If for some reason you don't / can't use Compass...

@function pow($number, $exp) {
  $value: 1;
  @if $exp > 0 {
    @for $i from 1 through $exp {
      $value: $value * $number;
    }
  }
  @else if $exp < 0 {
    @for $i from 1 through -$exp {
      $value: $value / $number;
    }
  }
  @return $value;
}

@function fact($number) {
  $value: 1;
  @if $number > 0 {
    @for $i from 1 through $number {
      $value: $value * $i;
    }
  }
  @return $value;
}

@function pi() {
  @return 3.14159265359;
}

@function rad($angle) {
  $unit: unit($angle);
  $unitless: $angle/($angle*0+1);
  @if $unit == deg {
    $unitless: $unitless / 180 * pi();
  }
  @return $unitless;
}

@function sin($angle) {
  $sin: 0;
  $angle: rad($angle);
  @for $i from 0 through 10 {
    $sin: $sin + pow(-1,$i) * pow($angle, (2*$i+1)) / fact(2 * $i + 1);
  }
  @return $sin;
}

@function cos($angle) {
  $cos: 0;
  $angle: rad($angle);
  @for $i from 0 through 10 {
    $cos: $cos + pow(-1,$i) * pow($angle, 2*$i) / fact(2 * $i);
  }
  @return $cos;
}

@function tan($angle) {
  @return sin($angle) / cos($angle);
}

@function sec($angle) {
  @return 1 / sin($angle);
}

@function csc($angle) {
  @return 1 / cos($angle);
}

@function cot($angle) {
  @return 1 / tan($angle);
}