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January 31, 2009
UnboundLocalError - Python Message
What does THIS mean?
UnboundLocalError: local variable 'taxrate' referenced before assignment
It means that you have tried to modify the value of a variable - perhaps in a function - before you have given it an initial value:
taxrate = 15
def getnet(gross):
taxrate /= 100.
net = gross - gross / (1.0 + taxrate)
return net
amount = getnet (230)
print amount
The variable taxrate is local to the getnet function ... the way the code is written, there is a DIFFERENT taxrate variable in the calling code.
You could share the variable by declaring it global in the function or - much better - you could use it read only in the function, in which case Python will see it from the outer scope.
So this will work:
taxrate = 15
def getnet(gross):
net = gross - gross / (1.0 + taxrate/100.0)
return net
amount = getnet (230)
print amount
And that's also far better because it doesn't alter the variable that contains the tax rate - rather it leaves it available for later use.
Posted by gje at January 31, 2009 06:09 AM