list comprehension in python
list:points=[('118.696', '55.016'), ('64.583', '195.986'), ('229.826', '259.417'), ('283.94', '118.447')]
list comprehension:
SyntaxError: invalid syntax
[(Decimal(x),Decimal(y)) for x,y in points]
Conclusion:
if you want to return a tuple, you have to speak it out:-)
another list comprehension:
for i,x,y in points:
result:SyntaxError: invalid syntax
try again:
for i,(x,y) in points:
conclusion:if you want to get a tuple, you'd better not put it next to others, here is index i, instead make it clear that it's a tuple.
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