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How to print a number with commas as thousands separators in JavaScript
... (since 789 is a multiple of 3 digits, 678 is a multiple of 3 digits, 567, etc.). The negative assertion checks that the multiple of 3 digits does not have any digits after it. 789 has a period after it so it is exactly a multiple of 3 digits, so a comma goes there. 678 is a multiple of 3 digits but...
How to check if all elements of a list matches a condition?
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The best answer here is to use all(), which is the builtin for this situation. We combine this with a generator expression to produce the result you want cleanly and efficiently. For example:
>>> items = [[1, 2, 0], [1, 2, 0], [1, 2, 0]]
>>...
How do I get the opposite (negation) of a Boolean in Python?
...ful if you want to use a function that requires a predicate-function or a callback.
For example map or filter:
>>> lst = [True, False, True, False]
>>> list(map(operator.not_, lst))
[False, True, False, True]
>>> lst = [True, False, True, False]
>>> list(filter...
Why is parenthesis in print voluntary in Python 2.7?
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In Python 2.x print is actually a special statement and not a function*.
This is also why it can't be used like: lambda x: print x
Note that (expr) does not create a Tuple (it results in expr), but , does. This likely results in the confusion between...
How to copy a row and insert in same table with a autoincrement field in MySQL?
....)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSERT column list and your SELECT:
insert into your_table (id, c1, c2, ...)
select 2, c1, c2, ...
from your_table
where i...
How do you deal with configuration files in source control?
...ntrol on the config files for each environment, can easily perform a diff, etc.
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Simplest/Cleanest way to implement singleton in JavaScript?
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return { // public interface
publicMethod1: function () {
// all private members are accessible here
},
publicMethod2: function () {
}
};
})();
This has been called the module pattern, it basically allows you to encapsulate private members on an object, by taking advant...
What would cause an algorithm to have O(log n) complexity?
...big-Oh of log(N) because there's no way to force it into the criteria we sketched out above.
You can pick that arbitrary constant to be c=10, and if your list has N=32 elements, you're fine: 10*log(32) = 50, which is greater than the runtime of 32. But if N=64, 10*log(64) = 60, which is less tha...
How to calculate the bounding box for a given lat/lng location?
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I suggest to approximate locally the Earth surface as a sphere with radius given by the WGS84 ellipsoid at the given latitude. I suspect that the exact computation of latMin and latMax would require elliptic functions and would not yield an appreciable ...
Catch an exception thrown by an async void method
...ET,
is it possible to catch an exception thrown by an async method in the calling method?
6 Answers
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