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pythonpandasnumpyflip-flop

Is it possible to implement RS flip flop truth table in Python?

I am new to Python. i am using Spyder (pandas and numpy) to run an algorithm for data analysis. This requires implementation of an RS flip flop on two variables in the data. something like this in C:

((R_b) != FALSE) ? (*(State_pb) = FALSE) : (((S_b) != FALSE) ? (*(State_pb) = TRUE) : *(State_pb));

Here R_b is the R input to the flip-flop and S-b is the S input. Note the use of pointer to the previous state of the flip flop to retain previous state . Could this be implemented in Python as well?

Solution

  • Here is a function that's a fairly direct translation of your C code, using Python's conditional operator.

    from itertools import product

def flipflop(state, r, s):
    return False if r else (True if s else state)

# test

print('state : r, s -> new_state')
for state, r, s in product((False, True), repeat=3):
    print('{!s:5} : {!s:5}, {!s:5} -> {!s:5}'.format(state, r, s, flipflop(state, r, s)))

    output

    state : r, s -> new_state
False : False, False -> False
False : False, True  -> True 
False : True , False -> False
False : True , True  -> False
True  : False, False -> True 
True  : False, True  -> True 
True  : True , False -> False
True  : True , True  -> False

    Note that neither this code nor your C code correctly handle the forbidden r == s == True input.