cv2 uses numpy for manipulating images, so the proper and best way to get the size of an image is using numpy.shape. Assuming you are working with BGR images, here is an example: In case you were working with binary images, img will have two dimensions, and therefore you must change the code to: height, … Read more
To have it print the letter grade as a user enters a score you can do something like: The letter grade problem was that you were using total which was all the grades added up (hopefully more than 100 if you got at least a 20 on all 5 assignments), so it would always default … Read more
If you don’t want to define a function before it’s used, and defining it afterwards is impossible, what about defining it in some other module? Technically you still define it first, but it’s clean. You could create a recursion like the following: Python’s functions are anonymous just like values are anonymous, yet they can be … Read more
Here are Windows wheel packages built by Chris Golke – Python Windows Binary packages – PyQt In the filenames cp27 means C-python version 2.7, cp35 means python 3.5, etc. Since Qt is a more complicated system with a compiled C++ codebase underlying the python interface it provides you, it can be more complex to build … Read more
r means the string will be treated as raw string. See the official Python 2 Reference about “String literals”: When an ‘r’ or ‘R’ prefix is present, a character following a backslash is included in the string without change, and all backslashes are left in the string. For example, the string literal r”\n” consists of two characters: a backslash and a lowercase ‘n’. String quotes can be … Read more
You have to run your script with ipython: Then get_ipython will be already in global context. Note: Importing it via from IPython import get_ipython in ordinary shell python will not work as you really need ipython running.
One thing to keep in mind is that a tuple is immutable. This means that once it’s created, you can’t modify it in-place. A list, on the other hand, is mutable — meaning you can add elements, remove elements, and change elements in-place. A list has extra overhead, so only use a list if you need to modify … Read more
I had the same problem. When I upgraded python3 through Homebrew, I started getting this: I had the same conflict with Python somehow being installed in /Library/Framework/Python.framework. I just did a brew link overwrite and everything is working fine now. There is some info about what to do with the Python version in the /Library/Framework/Python.framework here. I guess you could … Read more
pip’s documentation lists the supported mechanisms to install it: https://pip.pypa.io/en/stable/installation/#supported-methods It is generally recommended to avoid installing pip on the OS-provided python commands, and to install Python via the https://python.org installers or using something like Homebrew or pyenv. Python 3.4+ will have ensurepip, so if you’re unable to run python3 -m pip — run python3 -m ensurepip and it’ll install pip for you. If you’re using an end-of-life … Read more
I found this error, the cause was that there were some carriage returns “\r” in the data that pandas was using as a line terminator as if it was “\n”. I thought I’d post here as that might be a common reason this error might come up. The solution I found was to add lineterminator=’\n’ … Read more