190a392d_th_PHP___Page_2___WebReference__Flags
[Filter] FILTER_SANITIZE_NUMBER_FLOAT [Options] NO Options [Description] Removes all characters except digits and the plus and minus signs. The flags optionally permit a decimal fraction, the thousands separator, and scientific notation (using uppercase or lowercase E). The decimal point and thousands separator are left untouched. If not set, the decimal point is removed, but not the fraction, for example, 10.5 becomes 105. [Flags] 
FILTER_FLAG_ALLOW_FRACTION FILTER_FLAG_ALLOW_THOUSAND FILTER_FLAG_ALLOW_SCIENTIFIC
Data Filtering with PHP / Page 2 | WebReference
Flags