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What is the Java string pool and how is “s” different from new String(“s”)? [duplicate]
...terned. The
distinct values are stored in a string
intern pool.
Basically, a string intern pool allows a runtime to save memory by preserving immutable strings in a pool so that areas of the application can reuse instances of common strings instead of creating multiple instances of it.
As an ...
How do I create a variable number of variables?
... answered Sep 3 '09 at 12:41
c_harmc_harm
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...
Performance of Arrays vs. Lists
...
Very easy to measure...
In a small number of tight-loop processing code where I know the length is fixed I use arrays for that extra tiny bit of micro-optimisation; arrays can be marginally faster if you use the indexer / for form - but IIRC believe it dep...
get list from pandas dataframe column
...rame columns are Pandas Series when you pull them out, which you can then call x.tolist() on to turn them into a Python list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], inde...
How do you count the lines of code in a Visual Studio solution?
...x", "Cyclomatic Complexity", "Depth of Inheritance", and "Class Coupling", all of which are pretty complicated to compute, and you can't run the metrics for just part of it. What this means is that if your code-base is particularly large, you might be sitting for hours waiting for it. If all you w...
Convert string to binary in python
...encoding.
In Python 3, then, you can do something like this:
a = "test"
a_bytes = bytes(a, "ascii")
print(' '.join(["{0:b}".format(x) for x in a_bytes]))
The differences between UTF-8 and ascii encoding won't be obvious for simple alphanumeric strings, but will become important if you're process...
Avoid duplicates in INSERT INTO SELECT query in SQL Server
...
Using NOT EXISTS:
INSERT INTO TABLE_2
(id, name)
SELECT t1.id,
t1.name
FROM TABLE_1 t1
WHERE NOT EXISTS(SELECT id
FROM TABLE_2 t2
WHERE t2.id = t1.id)
Using NOT IN:
INSERT INTO TABLE_2
(id, name)
SELECT t...
How do I find all installed packages that depend on a given package in NPM?
...package.json, but I don't want to break something. Is there a way to list all of the installed packages that depend on it?
...
How can I remove a specific item from an array?
... first match of 5 from [2,5,9,1,5,8,5]), while the second function removes all occurrences:
function removeItemOnce(arr, value) {
var index = arr.indexOf(value);
if (index > -1) {
arr.splice(index, 1);
}
return arr;
}
function removeItemAll(arr, value) {
var i = 0;
...
Android: When is onCreateOptionsMenu called during Activity lifecycle?
...finishes onCreateOptionsMenu is called.
That will be true on devices and apps with an official Honeycomb-style action bar. If there is no action bar, onCreateOptionsMenu() should not get called until the user calls up the menu, typically by pressing the MENU button.
(I'm using screen size to d...