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How to print colored text in Python?
... the output to a file; while tools like cat may support colors, it is generally better to not print color information to files.
– Sebastian Mach
Apr 9 '14 at 6:27
1
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What is an idempotent operation?
...ng, an idempotent operation is one that has no additional effect if it is called more than once with the same input parameters. For example, removing an item from a set can be considered an idempotent operation on the set.
In mathematics, an idempotent operation is one where f(f(x)) = f(x). For exa...
SQlite Getting nearest locations (with latitude and longitude)
...n.
2) Now you can loop on these filtered data and determine if they are really near your point (in the circle) or not using the following methods:
public static boolean pointIsInCircle(PointF pointForCheck, PointF center,
double radius) {
if (getDistanceBetweenTwoPoints(pointFo...
Big O, how do you calculate/approximate it?
..., but be warned that this topic takes my students a couple of months to finally grasp. You can find more information on the Chapter 2 of the Data Structures and Algorithms in Java book.
There is no mechanical procedure that can be used to get the BigOh.
As a "cookbook", to obtain the BigOh from ...
How to convert floats to human-readable fractions?
....out r d
** r is real number to approx
** d is the maximum denominator allowed
**
** based on the theory of continued fractions
** if x = a1 + 1/(a2 + 1/(a3 + 1/(a4 + ...)))
** then best approximation is found by truncating this series
** (with some adjustments in the last term).
**
** Note the ...
seek() function?
...
Regarding seek() there's not too much to worry about.
First of all, it is useful when operating over an open file.
It's important to note that its syntax is as follows:
fp.seek(offset, from_what)
where fp is the file pointer you're working with; offset means how many positions you wi...
How to have an automatic timestamp in SQLite?
...
Just declare a default value for a field:
CREATE TABLE MyTable(
ID INTEGER PRIMARY KEY,
Name TEXT,
Other STUFF,
Timestamp DATETIME DEFAULT CURRENT_TIMESTAMP
);
However, if your INSERT command explicitly sets this field to N...
How to use double or single brackets, parentheses, curly braces
...veral more
Also, brace expansions create lists of strings which are typically iterated over in loops:
$ echo f{oo,ee,a}d
food feed fad
$ mv error.log{,.OLD}
(error.log is renamed to error.log.OLD because the brace expression
expands to "mv error.log error.log.OLD")
$ for num in {000..2}; do ech...
How can I delete a file from a Git repository?
...Git repository. After that, I committed it, added a couple of directories called dir1 and dir2 , and committed them to the Git repository.
...
pandas: filter rows of DataFrame with operator chaining
...
That is a really nice solution - I wasn't even aware that you could jury-rig methods like that in python. A function like this would be really nice to have in Pandas itself.
– naught101
Mar 3 '17 at...