how to concatenate two dictionaries to create a new one in Python?
Say I have three dicts How do I create a new d4 that combines these three dictionaries? i.e.:
python
Plot a histogram such that the total area of the histogram equals 1
When you plot a normalized histogram, it is not the height that should sum up to one, but the area underneath the curve should sum up to one: Here, this example, the bin width is 0.1, the area underneath the curve sums up to one (0.1*10). To have the sum of height to be 1, … Read more
Python iteration over non-sequence
You are trying to iterate over the object itself, which is returning the error. You want to iterate over the list inside the object, in this case Notes.notes (which is somewhat confusing naming, you may want to distinguish the internal list by using another name for the instance of the notebook object).
python regular expression “\1”
\1 is equivalent to re.search(…).group(1), the first parentheses-delimited expression inside of the regex. It’s also, fun fact, part of the reason that regular expressions are significantly slower in Python and other programming languages than required to be by CS theory.ShareFollowansw
How to open every file in a folder
Os You can list all files in the current directory using os.listdir: Glob Or you can list only some files, depending on the file pattern using the glob module: It doesn’t have to be the current directory you can list them in any path you want: Pipe Or you can even use the pipe as you specified using fileinput And … Read more
if else function in pandas dataframe
You can use numpy.where: Error is better explain here. Slowier solution with apply, where need axis=1 for data processing by rows: Also is possible use loc, but sometimes data can be overwritten:
Intel MKL FATAL ERROR: Cannot load mkl_intel_thread.dll
Maybe another DLL necessary for MKL, such as libiomp5md.dll for example, is missing and causes the error. See Cannot load mkl_intel_thread.dll on python executable, my answer there and its comments. If this still does not solve your problem, try to manually copy other DLLs from the anaconda environment’s library path into the app installation directory and its lib subdirectory. Once … Read more
What is a “slug” in Django?
A “slug” is a way of generating a valid URL, generally using data already obtained. For instance, a slug uses the title of an article to generate a URL. I advise to generate the slug by means of a function, given the title (or another piece of data), rather than setting it manually. An example: … Read more
How do you test that a Python function throws an exception?
Use TestCase.assertRaises (or TestCase.failUnlessRaises) from the unittest module, for example:
What is the difference between a string and a byte string?
Assuming Python 3 (in Python 2, this difference is a little less well-defined) – a string is a sequence of characters, ie unicode codepoints; these are an abstract concept, and can’t be directly stored on disk. A byte string is a sequence of, unsurprisingly, bytes – things that can be stored on disk. The mapping between them is … Read more