protected function GeneralNumberFormatter::numberFormatScientific in Formatter Suite 8

Formats a number using scientific notation.

Scientific notation formats a number with three parts:

• Whole part before the decimal.
• Fractional part after the decimal.
• Exponent for a power of 10.

Scientific notation follows international standards, so it is not subject to regional choices for a decimal separator and it does not support different positive and negative presentation styles.

The following formatting attributes are used:

• Exponent style.
• Decimal digits.

Parameters

mixed $number: The number to format.

Return value

string The formatted number, including the prefix or suffix.

1 call to GeneralNumberFormatter::numberFormatScientific()

GeneralNumberFormatter::numberFormat in src/Plugin/Field/FieldFormatter/GeneralNumberFormatter.php

Format a number using the current settings.

File

src/Plugin/Field/FieldFormatter/GeneralNumberFormatter.php, line 1363

Class

GeneralNumberFormatter

Format a number field with a variety of notation styles and parameters.

Namespace

Drupal\formatter_suite\Plugin\Field\FieldFormatter

Code

protected function numberFormatScientific($number) {

  // Get settings.
  $usePrefixAndSuffix = $this
    ->getSetting('usePrefixAndSuffix');
  $exponentStyle = $this
    ->getSetting('exponentStyle');
  $decimalDigits = $this
    ->getSetting('decimalDigits');

  // Use sprintf() to do an initial format into E-notation (the only
  // one sprintf() supports). sprintf() will handle scaling up/down the
  // number to a whole part with one digit, then calculating the
  // exponent.
  $fmt = '%' . ($decimalDigits + 2) . '.' . $decimalDigits . 'E';
  $formatted = sprintf($fmt, (double) $number);

  // Format the exponent.
  switch ($exponentStyle) {
    default:
    case 'enotation':

      // Use sprintf() output as-is since it produces E-notation.
      break;
    case 'superscript':

      // Split the formatted output at the 'E' into mantissa and exponent.
      // If this doesn't yield two parts, then the number was too small
      // and simple to have an exponent (e.g. "1.0"). Just use the
      // number as-is.
      $parts = explode('E', $formatted);
      if (count($parts) === 2) {
        $formattedMantissa = $parts[0];
        $formattedExponent = $parts[1];

        // Format the exponent using an HTML <sup> tag.
        $formatted = $formattedMantissa . 'x10<sup>' . $formattedExponent . '</sup>';
      }
      break;
  }

  // If needed, add the prefix and suffix.
  if ($usePrefixAndSuffix === FALSE) {
    return $formatted;
  }
  $prefixes = $this
    ->getFieldPrefixes();
  $suffixes = $this
    ->getFieldSuffixes();
  $prefix = $this
    ->selectPrefix($number, $prefixes);
  $suffix = $this
    ->selectSuffix($number, $suffixes);
  return $prefix . $formatted . $suffix;
}