The documentation says that __contains__ should return true if item is in self, false otherwise. However, if the method returns a non-boolean value x, it seems that python automatically converts it to bool(x).

## How to find mean of an array which has two elements in Python?

I need to find mean of an array which is like: [('a', 5), ('b', 2), ('a', 4), ('b', 6)]Result should be like; [('a', 4.5), ('b', 4)]

## Vectorize a 6 for loop cumulative sum in python

The mathematical problem is:The expression within the sums is actually much more complex than the one above, but this is for a minimal working example to not over-complicate things. I have written this in Python using 6 nested for loops and as expected it performs very badly (the true form...

## Converting input from non-integer bit rates into something workable

I have a program whose input has changed. It originally worked when using integers and the integers had units like: "kbps", "Mbps", "Gbps". An example:

## Is returning the intermediate value in a recursive function a quirk of python?

UPDATE: Let me clarify what exactly is so confusing about this. If I add a print statement like such:

## Functions, methods, and how many arguments do I have to give them?

Why do the following lines give me the same result?andI tried to do the same with list.append but got a TypeError.

## Python decorator to time recursive functions

I have a simple decorator to track the runtime of a function call:This can be used as follows, and returns a tuple of the function result and the execution time.

## Pandas Groupby using multiple criteria on different axis

I have a df DataFrame like : And I want to group all columns X with X_ for all letters A,B,... (let's say, the group is called X as well), and group as well using COMMON. I would like to apply later function like std() to all the grouped values.

## check if letters of a string are in sequential order in another string

If it were just checking whether letters in a test_string are also in a control_string, I would not have had this problem.

## Merging data based on matching first column in Python

I currently have two sets of data files that look like this:File 1:and in file 2:I would like to combine the files based on mathching rows in the first column (so that "tests" match up)