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JavaScript null check
... value undefined.
An undefined variable:
var a;
alert(b); // ReferenceError: b is not defined
A variable with the value undefined:
var a;
alert(a); // Alerts “undefined”
When a function takes an argument, that argument is always declared even if its value is undefined, and so there won’...
How to capitalize the first letter in a String in Ruby
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It depends on which Ruby version you use:
Ruby 2.4 and higher:
It just works, as since Ruby v2.4.0 supports Unicode case mapping:
"мария".capitalize #=> Мария
Ruby 2.3 and lower:
"maria".capitalize #=> "Maria"
"мария".capitalize #=> мария
The problem is, it just...
How to return a value from __init__ in Python?
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__init__ is required to return None. You cannot (or at least shouldn't) return something else.
Try making whatever you want to return an instance variable (or function).
>>> class Foo:
... def __init__(self):
... return 42
...
>>> foo = Foo(...
Can I use complex HTML with Twitter Bootstrap's Tooltip?
... answered Dec 4 '12 at 14:43
George WilsonGeorge Wilson
5,20344 gold badges2525 silver badges4141 bronze badges
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How can I determine the current line number in JavaScript?
Does JavaScript have a mechanism for determining the line number of the currently executing statement (and if so, what is it)?
...
Is PHP compiled or interpreted?
Is PHP compiled or interpreted?
9 Answers
9
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align text center with android
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Set also android:gravity parameter in TextView to center.
For testing the effects of different layout parameters I recommend to use different background color for every element, so you can see how your layout changes with parameters like gravity, layout_gravity or others.
...
How to add an empty column to a dataframe?
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If I understand correctly, assignment should fill:
>>> import numpy as np
>>> import pandas as pd
>>> df = pd.DataFrame({"A": [1,2,3], "B": [2,3,4]})
>>> df
A B
0 1 2
1 2 3
2 3 4
>>> df[...
Ubuntu rails install fails on zlib
I've just moved over to Ubuntu 8.10 as my dev box; it's my first serious foray into Linux as a daily-use OS, and I'm having a hard time getting Rails going. I have followed a number of tutorials which all seem to work fine, but when I try and use gem install or gem update on anything, I get an erro...
Freely convert between List and IEnumerable
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You also could just use the original myList object. (I guess I don't really get the question)
– sth
Jan 23 '09 at 12:27
6
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