print 3 return values from function

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print 3 return values from function - bluefrog - Mar-05-2017

Hi

I am attempting to print the values returned from the function, defined as follows:

def calc_accuracy(p_RDD, model):
  correct = p_RDD.map( lambda lp: 1 if model.predict(lp.features) == lp.label else 0).sum()
  count = p_RDD.count()
  accuracy = correct/count
  return correct, count, accuracy

but I get the following error:

---> 27   print('train set correct: {}, of total: {}, accuracy: {}'.format(calc_accuracy(train_RDD, model)) )

IndexError: tuple index out of range

Can anybody suggest a way I can call the function within a print ?
Thanks

RE: print 3 return values from function - wavic - Mar-05-2017

just print it without formatting to see what the function returns.

RE: print 3 return values from function - zivoni - Mar-05-2017

Format expects 3 values, so unpack your tuple with *:

print('train set correct: {}, of total: {}, accuracy: {}'.format( *calc_accuracy(train_RDD, model)) )

RE: print 3 return values from function - buran - Mar-05-2017

star-unpack the tuple returned by your function

print('train set correct: {}, of total: {}, accuracy: {}'.format(*calc_accuracy(train_RDD, model)))

RE: print 3 return values from function - bluefrog - Mar-05-2017

thanks, zivoni, buran,

that worked!

RE: print 3 return values from function - wavic - Mar-05-2017

Wow! I have learned one more thing Shy