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How do Trigonometric functions work?
So in high school math, and probably college, we are taught how to use trig functions, what they do, and what kinds of problems they solve. But they have always been presented to me as a black box. If you need the Sine or Cosine of something, you hit the sin or cos button on your calculator and you'...
Why start an ArrayList with an initial capacity?
...t 8 elements. Insert one (cost: 1). Insert two -- double, copy one element and insert two (cost: 2). Insert three -- double, copy two elements, insert three (cost: 3). Insert four (cost: 1). Insert five -- double, copy four elements, insert five (cost: 5). Insert six, seven and eight (cost: 3). Tota...
href=“tel:” and mobile numbers
...ant to dial via the international trunk, you need to drop the trunk prefix and replace it with the international dialing prefix
+ - Short hand for the country trunk number
61 - Country code for Australia
4 - Area code for a mobile telephone
1234 5678 - Mobile telephone number...
How to open every file in a folder?
...have a python script parse.py, which in the script open a file, say file1, and then do something maybe print out the total number of characters.
...
URL encoding the space character: + or %20?
When is a space in a URL encoded to + , and when is it encoded to %20 ?
4 Answers
4
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Re-raise exception with a different type and message, preserving existing information
I'm writing a module and want to have a unified exception hierarchy for the exceptions that it can raise (e.g. inheriting from a FooError abstract class for all the foo module's specific exceptions). This allows users of the module to catch those particular exceptions and handle them distinctly,...
How do I move forward and backward between commits in git?
I am doing a git bisect and after arriving to the problematic commit, I am now trying to get a step forward/backward to make sure I am in the right one.
...
Dealing with multiple Python versions and PIP?
...This is the recommendation because it works across all versions of Python, and in all forms of virtualenv. For example:
# The system default python:
$ python -m pip install fish
# A virtualenv's python:
$ .env/bin/python -m pip install fish
# A specific version of python:
$ python-3.6 -m pip inst...
Is it possible to declare two variables of different types in a for loop?
...se a structured binding declaration. The syntax has been supported in gcc and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so:
for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) {
// ...
}
The above...
Class method differences in Python: bound, unbound and static
...
In Python, there is a distinction between bound and unbound methods.
Basically, a call to a member function (like method_one), a bound function
a_test.method_one()
is translated to
Test.method_one(a_test)
i.e. a call to an unbound method. Because of that, a call to...