Given a list xs and a value item, how can I check whether xs contains item (i.e., if any of the elements of xs is equal to item)? Is there something like xs.contains(item)? For performance considerations, see Fastest way to check if a value exists in a list. Answer Use: Also, inverse operation: It works fine for lists, tuples, sets
Tag: list
How to find out the words begin with vowels in a list?
My code doesn’t right, and it will print out all the words in the original list. Answer You can also use a list comprehension like this
“Josephus-problem” using list in python
I wanted to know if it will be possible to solve the Josepheus problem using list in python. In simple terms Josephus problem is all about finding a position in a circular arrangement which would be safe if executions were handled out using a skip parameter which is known beforehand. For eg : given a circular arrangement such as [1,2,3,4,5,6,7]
How to get first element in a list of tuples?
I have a list like below where the first element is the id and the other is a string: I want to create a list of ids only from this list of tuples as below: I’ll use this list in __in so it needs to be a list of integer values. Answer
Generate list of numbers in specific format
I need to generate a list of numbers in a specific format. The format is I know how to generate a normal list of numbers using range So, is there any built-in way in python to generate a list of numbers in the specified format. Answer Python string formatting allows you to specify a precision: Precision (optional), given as a
Print list without brackets in a single row
I have a list in Python e.g. I want to print the array in a single line without the normal ” [] Will give the output as; That is not the format I want instead I want it to be like this; Note: It must be in a single row. Answer This, like it sounds, just takes all the elements
Python, converting a list of indices to slices
So I have a list of indices, and want to convert it to this, this will run on a large number of indices. Also, this technically isn’t for slices in python, the tool I am working with is faster when given a range compared to when given the individual ids. The pattern is based on being in a range, like
Python itertools.product with variable number of arguments
I am trying to write a module to combine a variable number of lists using itertools.product. The closest I can get is: This doesn’t work, because lists is a single list, so it just returns the original sequence. But I can’t figure out how to pass each element of the lists variable to itertools. Thanks for any suggestions. Answer You
python numpy split array into unequal subarrays
I am trying to split an array into n parts. Sometimes these parts are of the same size, sometimes they are of a different size. I am trying to use: This works fine when size divides equally into the list, but fails otherwise. Is there a way to do this which will ‘pad’ the final array with the extra ‘few’
Remove duplicate dict in list in Python
I have a list of dicts, and I’d like to remove the dicts with identical key and value pairs. For this list: [{‘a’: 123}, {‘b’: 123}, {‘a’: 123}] I’d like to return this: [{‘a’: 123}, {‘b’: 123}] Another example: For this list: [{‘a’: 123, ‘b’: 1234}, {‘a’: 3222, ‘b’: 1234}, {‘a’: 123, ‘b’: 1234}] I’d like to return this: [{‘a’: