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PYTHON 3.5 RUNTIME ERROR

unorderable types: list() > float()

During backtest when using the default python 3.5 i had this runtime error at 10 May 2019, but it it works fine under python 2.7. Any ideas, guys?

1 response

There should be a line number and the offending code printed underneath the error. Check out that line and you will find the culprit. Judging from the error message you probably have a comparison something like this

# There is a list with a single item. As an example 99.  
my_list = [99]  
# This list is being compared to a floating point value  
my_comparison = my_list > 1.0

In Python 3.5 this causes an error. In 2.7 it doesn't. You may not have originally realized in your code that 'my_list' was a list. You may have assumed it was a scaler value. The solution is to explicitly select the item of the list one wants to compare (probably the first?).

# Select an item from the list then compare. An easy way is with list indexing.  
my_comparison = my_list[0] > 1.0

The above will work in both Python 2.7 and 3.5.

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