Imagine I have a dataframe with user events For each user after his last (by timestamp) event I want to add new row with ‘End’ event with the same timestamp as in previous event: I have no idea how to do that. In SQL I would do that with LAG() or LEAD(). But what about pandas? Answer Use DataFrame.drop_duplicates for
Python: How do you remove a dict in a list of dicts of list of dicts? [closed]
Closed. This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 2 years ago. The community is reviewing whether to reopen this question as of 1 year ago. Improve this question as a startingpoint i have this
Check if the browser opened with Selenium is still running (Python)
I want to check if a browser opened with Selenium is still open. I would need this check for closing a program. If the browser is not open, then the GUI should be destroyed without a message (tk.messagebox) coming. But if the browser is open, then the message should come as soon as the function is activated. Here is the
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Recently, I’ve been trying to load some grayscale images into my Python program using Pillow’s Image.open(). However, I’ve been finding that the image gets distorted, and all the values polarized. This is the image generated by the Mac preview: And, this is the image generated by the Image.open() function: My code is as follows: And, the characteristics of the image
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Suppose I have a dataframe as follows how can I merge the two columns into one using pandas? The desired output is output Thank you! Answer Use Series.fillna with DataFrame.pop for replace missing values to another column with drop second column: Or you can back filling missing values with select first column by DataFrame.iloc with [[0]] for one column DataFrame
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I am trying to solve a problem and my code fails at one test case where the list is of length 25000. Is there any way I can make this faster. I tried using functools.lru_cache and I still can not run within the time required to complete. This is the problem from the site Given an array of non-negative integers
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what is the difference and uses of these lines of code?
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Return same position for similar values in a list
I have sorted a list in descending order, I am trying to find a way in which similar numbers re-appearing in the list will return equal position and the next unique number to return the next position. Example in this samplelist = [50, 40, 40, 30, 30, 20, 10] 50 should return 1, 40 returns 2, next 40 returns 2,
Unresolved imports in VSCode Python
While programming in VSCode, Python I imported a module named Selenium. However, VS Code is Showing me an error, saying unresolved import selenium. I had installed selenium yesterday only using the pip command. Please do help me out Answer It is recommended that you use the command “python –version”(or python3 –version) in the VS Code terminal to check whether the