WordPress Number library.
composer require pronamic/wp-number
$number = Number::from_float( 123.50 )->add( 0.45 );
echo \esc_html( $number->format_i18n( 2 ) );
In general, a number is a number, not a string, and this means that any programming language treats a number as a number. Thus, the number by itself doesn't imply any specific format (like using .000021 instead of 2.1e-5). This is nothing different to displaying a number with leading zeros (like 0.000021) or aligning lists of numbers. This is a general issue you'll find in any programming language: if you want a specific format you need to specify it, using the format functions of your programming language.
Unless you specify the number as string and convert it to a real number when needed, of course. Some languages can do this implicitly.
https://stackoverflow.com/a/1471792
2.1E-5 is the same number as 0.000021. That's how it prints numbers below 0.001. Use printf() if you want it in a particular format.
Edit If you're not familiar with the
2.1E-5syntax, you should know it is shorthand for 2.1×10-5. It is how most programming languages represent numbers in scientific notation.
https://stackoverflow.com/a/1471694
In https://github.com/moneyphp/money it is not allowed to use leading zeros:
Leading zeros are not allowed
Source: https://github.com/moneyphp/money/search?q=leading+zero
This probably has somehting to do with the following user note:
Be careful with GMP - it considers leading zeros in a number string as meaning the number is in octal, whereas 'bc' doesn't:
gmp_strval("000100", 10) => 64
bcmul("000100", "1") => 100
Source: https://www.php.net/manual/en/book.gmp.php#106521
<?php
$a = 1234; // decimal number
$a = 0123; // octal number (equivalent to 83 decimal)
$a = 0x1A; // hexadecimal number (equivalent to 26 decimal)
$a = 0b11111111; // binary number (equivalent to 255 decimal)
$a = 1_234_567; // decimal number (as of PHP 7.4.0)
?>Source: https://www.php.net/manual/en/language.types.integer.php
A leading zero in a numeric literal means "this is octal". But don't be confused: a leading zero in a string does not. Thus:
$x = 0123; // 83$y = "0123" + 0 // 123
Source: https://www.php.net/manual/en/language.types.integer.php#111523
