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What is the difference between 127.0.0.1 and localhost
... still have to do an actual lookup of localhost somewhere.
If you use 127.0.0.1, then (intelligent) software will just turn that directly into an IP address and use it. Some implementations of gethostbyname will detect the dotted format (and presumably the equivalent IPv6 format) and not do a looku...
How to create multidimensional array
...ar numeric = [
['input1','input2'],
['input3','input4']
];
numeric[0][0] == 'input1';
numeric[0][1] == 'input2';
numeric[1][0] == 'input3';
numeric[1][1] == 'input4';
var obj = {
'row1' : {
'key1' : 'input1',
'key2' : 'input2'
},
'row2' : {
'key3' : 'inpu...
Detect if value is number in MySQL
...
answered Feb 21 '11 at 10:47
RichardTheKiwiRichardTheKiwi
96.3k2323 gold badges178178 silver badges250250 bronze badges
...
What does the ^ operator do in Java?
...perator.
Let's take 5^6 as example:
(decimal) (binary)
5 = 101
6 = 110
------------------ xor
3 = 011
This the truth table for bitwise (JLS 15.22.1) and logical (JLS 15.22.2) xor:
^ | 0 1 ^ | F T
--+----- --+-----
0 | 0 1 F | F T
1 | 1 0 T | T...
Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
...vel, there is an associated column in a new data frame, which contains a 1/0 indicator. E.g., suppose I have:
8 Answers
...
Gray out image with CSS?
...age" src="something.jpg" />
</div>
css:
#myImage {
opacity: 0.4;
filter: alpha(opacity=40); /* msie */
}
/* or */
#wrapper {
opacity: 0.4;
filter: alpha(opacity=40); /* msie */
background-color: #000;
}
...
Two color borders
...utline is inside of the shadow; in FireFox it is outside, so -moz-outline: 0 is useful to ensure that you don't get a gnarly line around your beautiful CSS drop shadow).
.someclass {
border: 1px solid blue;
outline: 1px solid darkblue;
}
Edit: Some people have remarked that outline doesn't ji...
Regular expression for matching latitude/longitude coordinates?
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answered Aug 19 '10 at 3:38
Eric CEric C
3,55633 gold badges2828 silver badges2626 bronze badges
...
SQL Logic Operator Precedence: And and Or
...e's an example to illustrate:
Declare @x tinyInt = 1
Declare @y tinyInt = 0
Declare @z tinyInt = 0
Select Case When @x=1 OR @y=1 And @z=1 Then 'T' Else 'F' End -- outputs T
Select Case When (@x=1 OR @y=1) And @z=1 Then 'T' Else 'F' End -- outputs F
For those who like to consult references (in al...
Modifying a subset of rows in a pandas dataframe
...fy this DataFrame (or create a copy) so that B is always NaN whenever A is 0. How would I achieve that?
5 Answers
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