Python fastest byte to string conversion

Question

I need to convert a byte array to a string to send to an SPI device.

Is there a more efficient way of doing this ?

def writebytes(bytes):
  str = ""
  for i in bytes: str += chr(i)
  self.spi.transfer(str)

score 5 · Accepted Answer · answered Jul 15 '14 at 13:13

5

Use "".join with a generator expression.

def writebytes(bytes):
    self.spi.transfer("".join(chr(i) for i in bytes))

answered Jul 15 '14 at 13:13

chepner

1

Actually, using generator expression is slower than using simple `"".join(map(char, bytes))` because when a generator expression is passed, `join` has to iterate over the results to get the total length of input and save them for later. When passing a list, the elements will be available anytime. – Maciej Gol Oct 20 '15 at 19:10

1 Answers1