Other than the standard +, -, *and / operators; but what does these mean (** , ^ , %, //) ? >>> 9+float(2) # addition 11.0 >>> 9-float(2) # subtraction 7.0 >>> 9*float(2) # multiplication 18.0 >>> 9/float(2) # division 4.5 >>> >>> 9**float(2) # This looks like a square, (i.e. power 2) 81.0 >>> … Read more
I’m doing different text classification experiments. Now I need to calculate the AUC-ROC for each task. For the binary classifications, I already made it work with this code:
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How do you convert a grayscale OpenCV image to black and white? I see a similar question has already been asked, but I’m using OpenCV 2.3, and the proposed solution no longer seems to work.
How do I catch a Ctrl+C in multiprocess python program and exit all processes gracefully, I need the solution to work both on unix and windows. I’ve tried the following: import multiprocessing import time import signal import sys jobs = [] def worker(): signal.signal(signal.SIGINT, signal_handler) while(True): time.sleep(1.1234) print "Working…" def signal_handler(signal, frame): print 'You pressed … Read more
It seems rare to read of a Python “virtual machine” while in Java “virtual machine” is used all the time.
How do I add an item to an existing dictionary in Python? For example, given: default_data = { 'item1': 1, 'item2': 2, } I want to add a new item such that: default_data = default_data + {'item3': 3} Answers: Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may … Read more
Assume I have a program that uses argparse to process command line arguments/options. The following will print the ‘help’ message:
I was just testing an example from Numerical Methods in Engineering with Python.
I have a script that generates two-dimensional numpy arrays with dtype=float and shape on the order of (1e3, 1e6). Right now I’m using np.save and np.load to perform IO operations with the arrays. However, these functions take several seconds for each array. Are there faster methods for saving and loading the entire arrays (i.e., without making assumptions about their contents and reducing them)? I’m open to converting the arrays to another type before saving as long as the data are retained exactly.