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Create an empty data.frame
...not prevent further additions of rows having columns of different types.
This method is just a bit safer in the sense that you'll have the correct column types from the beginning, hence if your code relies on some column type checking, it will work even with a data.frame with zero rows.
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How to make a countdown timer in Android?
...inutes and in another EditText, a number as seconds. After clicking the finish button, the seconds EditText should start to countdown and update its text every second.
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How do I get the difference between two Dates in JavaScript?
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In JavaScript, dates can be transformed to the number of milliseconds since the epoc by calling the getTime() method or just using the date in a numeric expression.
So to get the difference, just subtract the two dates.
To create a new date based on the difference, just pass the numb...
How to use multiple AWS Accounts from the command line?
I've got two different apps that I am hosting (well the second one is about to go up) on Amazon EC2.
7 Answers
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Where in an Eclipse workspace is the list of projects stored?
I use Eclipse with "external" projects - i.e. projects created from existing source.
6 Answers
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What is the syntax for a default constructor for a generic class?
Is it forbidden in C# to implement a default constructor for a generic class?
3 Answers
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How do I get elapsed time in milliseconds in Ruby?
...ich can easily be converted.
For example:
def time_diff_milli(start, finish)
(finish - start) * 1000.0
end
t1 = Time.now
# arbitrary elapsed time
t2 = Time.now
msecs = time_diff_milli t1, t2
You will need to decide whether to truncate that or not.
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How to create a css rule for all elements except one class?
I have created a CSS stylesheet for my project. Is there any way I can create a css rule that applies to all table elements EXCEPT table elements belonging to the class "dojoxGrid"? Something like:
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How to debug external class library projects in visual studio?
...that references an assembly from an external project(B) class library that is located in another vs solution.
7 Answers
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nano error: Error opening terminal: xterm-256color
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On Red Hat this worked for me:
export TERM=xterm
further info here: http://www.cloudfarm.it/fix-error-opening-terminal-xterm-256color-unknown-terminal-type/
sh...