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Detect if value is number in MySQL
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answered Feb 21 '11 at 10:47
RichardTheKiwiRichardTheKiwi
96.3k2323 gold badges178178 silver badges250250 bronze badges
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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
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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;
}
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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...
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...
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
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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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deleting rows in numpy array
... [7,8,9]])
To delete the first row, do this:
x = numpy.delete(x, (0), axis=0)
To delete the third column, do this:
x = numpy.delete(x,(2), axis=1)
So you could find the indices of the rows which have a 0 in them, put them in a list or a tuple and pass this as the second argument of the...
How to decide font color in white or black depending on background color?
...overall intensity of the color and choose the corresponding text.
if (red*0.299 + green*0.587 + blue*0.114) > 186 use #000000 else use #ffffff
The threshold of 186 is based on theory, but can be adjusted to taste. Based on the comments below a threshold of 150 may work better for you.
Edit: T...