如何将浮点数存储为文本而不会丢失精度？

Question

Like the question says. Converting to / from the (truncated) string representations can affect their precision. But storing them in other formats like pickle makes them unreadable (yes, I want this too).

How can I store floating point numbers in text without losing precision?

Answer 1

Store it in binary or a power thereof.

>>> (3.4).hex()
'0x1.b333333333333p+1'

>>> float.fromhex('0x1.b333333333333p+1')
3.4

Answer 2

I'd suggest using the builtin function repr() . From the documentation:

repr(object) -> string

Return the canonical string representation of the object. For most object types, eval(repr(object)) == object.

Answer 3

pickle.dumps会这样做，但我相信float(str(floatval)) == floatval也是如此 - 至少在同一系统上......