import re

yes = re.compile(r'^(yes|true|on|1)', re.IGNORECASE)
no = re.compile(r'^(no|false|off|0)', re.IGNORECASE)
der0th = re.compile(r'^(0|none|energy)', re.IGNORECASE)
der1st = re.compile(r'^(1|first|gradient)', re.IGNORECASE)
der2nd = re.compile(r'^(2|second|hessian)', re.IGNORECASE)
