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Length of a JavaScript object
...an break enumerations in various libraries. Adding methods to Object is usually safe, though.
Here's an update as of 2016 and widespread deployment of ES5 and beyond. For IE9+ and all other modern ES5+ capable browsers, you can use Object.keys() so the above code just becomes:
var size = Object...
Best way to handle list.index(might-not-exist) in python?
...thonic solution is to use only try/except and not the -1 sentinel value at all. I.E. you should rewrite otherfunction. On the other hand, if it ain't broke, ...
– Andrew Jaffe
Jan 25 '10 at 15:49
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Meaning of 'const' last in a function declaration of a class?
...e that is often broken and easily broken.
foobar& fbNonConst = const_cast<foobar&>(fb1);
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adding noise to a signal in python
...umpy as np
import matplotlib.pyplot as plt
t = np.linspace(1, 100, 1000)
x_volts = 10*np.sin(t/(2*np.pi))
plt.subplot(3,1,1)
plt.plot(t, x_volts)
plt.title('Signal')
plt.ylabel('Voltage (V)')
plt.xlabel('Time (s)')
plt.show()
x_watts = x_volts ** 2
plt.subplot(3,1,2)
plt.plot(t, x_watts)
plt.title...
Define variable to use with IN operator (T-SQL)
... myColumn in (SELECT id FROM myIdTable WHERE id > 10)
2) Using dynamically concatenated TSQL
DECLARE @sql varchar(max)
declare @list varchar(256)
select @list = '1,2,3'
SELECT @sql = 'SELECT * FROM myTable WHERE myColumn in (' + @list + ')'
exec sp_executeSQL @sql
3) A possible third ...
Remove last character from string. Swift language
...answered Jul 24 '14 at 11:28
gui_dosgui_dos
1,19377 silver badges55 bronze badges
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Regex, every non-alphanumeric character except white space or colon
...
[^a-zA-Z\d\s:]
\d - numeric class
\s - whitespace
a-zA-Z - matches all the letters
^ - negates them all - so you get - non numeric chars, non spaces and non colons
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Get all directories within directory nodejs
...
Here's a shorter, syncronous version of this answer that can list all directories (hidden or not) in the current directory:
const { lstatSync, readdirSync } = require('fs')
const { join } = require('path')
const isDirectory = source => lstatSync(source).isDirectory()
const getDirectori...
Android: how to make keyboard enter button say “Search” and handle its click?
...w v, int actionId, KeyEvent event) {
if (actionId == EditorInfo.IME_ACTION_SEARCH) {
performSearch();
return true;
}
return false;
}
});
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What is memoization and how can I use it in Python?
...orials using memoization in Python would be something like this:
factorial_memo = {}
def factorial(k):
if k < 2: return 1
if k not in factorial_memo:
factorial_memo[k] = k * factorial(k-1)
return factorial_memo[k]
You can get more complicated and encapsulate the memoization...