0) ? \$match[4] : \$match[2]); // Remove traililng 0's from fraction, then add the decimal and one trailing // 0 and a space. The space serves as a way to always sort shorter decimal // numbers that match exactly as less than longer ones. // Ex: 3.05 and 3.05011. \$fraction = trim('.' . \$match[3], '0') . '0 '; \$encode = sprintf('%02u', strlen(\$whole)) . \$whole . \$fraction; if (strlen(\$match[1])) { // Negative number. Make 10's complement. Put back any leading white space // and the dash requires intermediate to avoid double-replacing the same // digit. str_replace() seems to work by copying the source to the result, // then successively replacing within it, rather than replacing from the // source to the result. // In this case since rules are reverced we also have to use a character // that would be sorted higher than a space when a number is being compared // against a longer one that is identical in negative numbers. This is so // that longer numbers are always LESS than sorter numbers that have // identical beginnings. Ex: -3.05 and -3.05011. \$digits = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', ' ']; \$intermediate = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k']; \$rev_digits = ['9', '8', '7', '6', '5', '4', '3', '2', '1', '0', ':']; \$encode = \$match[1] . str_replace(\$intermediate, \$rev_digits, str_replace(\$digits, \$intermediate, \$encode)); } return \$encode; }