I am trying to convert for example:
6.09677e-321 -> 1234
in c you can do something like: printf("%lld", 6.09677e-321)
Any ideas of how to get that casting into python?
I've tried with ctypes, d=c_float(6.09677e-321);cast(f, c_longlong) but didn't get much out of it.
You can also use the struct module for this:
>>> import struct
# treat the value as a double
>>> packed = struct.pack("d", 6.097e-321)
>>> packed
'\xd2\x04\x00\x00\x00\x00\x00\x00'
# ...but unpack it as a long int
>>> unpacked = struct.unpack("l", packed)
>>> unpacked[0]
1234
Python int and float types are not like primitive C numeric types. They are full-fledged objects. Python objects don't really have "casts" in that sense. However, you can do this using ctypes, which essentially provides object-oriented wrappers over primitive C types. It will be a little convoluted though:
import ctypes
py_float = 6.097e-321
cf = ctypes.c_double(py_float)
lp = ctypes.cast(ctypes.pointer(cf), ctypes.POINTER(ctypes.c_int64))
py_int = lp.contents.value
print(py_int) # 1234
