TypeError: not all arguments converted during string formatting python

Youre mixing different format functions.

The old-style % formatting uses % codes for formatting:

It will cost $%d dollars. % 95

The new-style {} formatting uses {} codes and the .format method

It will cost ${0} dollars..format(95)

Note that with old-style formatting, you have to specify multiple arguments using a tuple:

%d days and %d nights % (40, 40)

In your case, since youre using {} format specifiers, use .format:

{0} is longer than {1}.format(name1, name2)

The error is in your string formatting.

The correct way to use traditional string formatting using the % operator is to use a printf-style format string (Python documentation for this here: http://docs.python.org/2/library/string.html#format-string-syntax):

%s is longer than %s % (name1, name2)

However, the % operator will probably be deprecated in the future. The new PEP 3101 way of doing things is like this:

{0} is longer than {1}.format(name1, name2)

For me, This error was caused when I was attempting to pass in a tuple into the string format method.

Copying and pasting the correct answer from the link (NOT MY WORK):

>>> thetuple = (1, 2, 3)
>>> print this is a tuple: %s % (thetuple,)
this is a tuple: (1, 2, 3)

Making a singleton tuple with the tuple of interest as the only item,
i.e. the (thetuple,) part, is the key bit here.