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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...
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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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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...
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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...
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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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How to validate an Email in PHP?

...LTER_VALIDATE_EMAIL) PHP Manual filter_var() Available in PHP >= 5.2.0 If you don't want to change your code that relied on your function, just do: function isValidEmail($email){ return filter_var($email, FILTER_VALIDATE_EMAIL) !== false; } Note: For other uses (where you need Regex)...
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Regular expression for matching latitude/longitude coordinates?

... answered Aug 19 '10 at 3:38 Eric CEric C 3,55633 gold badges2828 silver badges2626 bronze badges ...
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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...
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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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Any reason not to use '+' to concatenate two strings?

... | edited Jan 10 '16 at 12:44 seriousdev 6,91188 gold badges4040 silver badges5050 bronze badges ...