otp.misc.hash_code#

hash_code(value, hash_type)#

Returns hexadecimal encoded hash code for the specified string with the specified hash function.

Parameters:

value (str, Operation, Column) – value to calculate hash from
hash_type (str) –
one of following hash types:
- sha_1
- sha_224
- sha_256
- sha_384
- sha_512
- lookup3
- metro_hash_64
- city_hash_64
- murmur_hash_64
- sum_of_bytes
- default

Return type:

Operation

Note

Fixed sized string hash result could differ from the same variable length string due to trailing nulls.

Examples

Basic example:

>>> data = otp.Tick(A=1)
>>> data['HASH'] = otp.hash_code('some_string', 'sha_224')
>>> otp.run(data)
        Time  A                                                      HASH
0 2003-12-01  1  12d3f96511450121e6343b5ace065ec9de7b2a946b86f7dfab8ac51f

You can also pass Operation as a value parameter:

>>> data = otp.Tick(A=otp.varstring('some_string'))
>>> data['HASH'] = otp.hash_code(data['A'], 'sha_224')
>>> otp.run(data)
        Time            A                                                      HASH
0 2003-12-01  some_string  12d3f96511450121e6343b5ace065ec9de7b2a946b86f7dfab8ac51f

For the same string stored in strings with different fixed sizes, the hash value may differ:

>>> test_str = 'example'
>>> data = otp.Tick(A=otp.string[128](test_str))
>>> data['Fixed'] = otp.hash_code(data['A'], 'sha_1')
>>> data['Var'] = otp.hash_code(otp.varstring(test_str), 'sha_1')
>>> otp.run(data)
        Time        A                                     Fixed                                       Var
0 2003-12-01  example  bdab82ec533c09646e45f15dc4e7ad2d2d1a8ff1  c3499c2729730a7f807efb8676a92dcb6f8a3f8f