python - Comment parser une chaîne à un flotteur ou un int

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>>> a = "545.2222" >>> float(a) 545.22220000000004 >>> int(float(a)) 545 

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def is_float(value):   try:     float(value)     return True   except:     return False 

val                   is_float(val) Note --------------------  ----------   -------------------------------- ""                    False        Blank string "127"                 True         Passed string True                  True         Pure sweet Truth "True"                False        Vile contemptible lie False                 True         So false it becomes true "123.456"             True         Decimal "      -127    "      True         Spaces trimmed "\t\n12\r\n"          True         whitespace ignored "NaN"                 True         Not a number "NaNanananaBATMAN"    False        I am Batman "-iNF"                True         Negative infinity "123.E4"              True         Exponential notation ".1"                  True         mantissa only "1,234"               False        Commas gtfo u'\x30'               True         Unicode is fine. "NULL"                False        Null is not special 0x3fade               True         Hexadecimal "6e7777777777777"     True         Shrunk to infinity "1.797693e+308"       True         This is max value "infinity"            True         Same as inf "infinityandBEYOND"   False        Extra characters wreck it "12.34.56"            False        Only one dot allowed u'四'                 False        Japanese '4' is not a float. "#56"                 False        Pound sign "56%"                 False        Percent of what? "0E0"                 True         Exponential, move dot 0 places 0**0                  True         0___0  Exponentiation "-5e-5"               True         Raise to a negative number "+1e1"                True         Plus is OK with exponent "+1e1^5"              False        Fancy exponent not interpreted "+1e1.3"              False        No decimals in exponent "-+1"                 False        Make up your mind "(1)"                 False        Parenthesis is bad 

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def num(s):     try:         return int(s)     except ValueError:         return float(s) 

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>>> import ast >>> ast.literal_eval("545.2222") 545.2222 >>> ast.literal_eval("31") 31 

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float(x) if '.' in x else int(x)