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How do I convert a TimeSpan to a formatted string? [duplicate]
I have two DateTime vars, beginTime and endTime. I have gotten the difference of them by doing the following:
14 Answers
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Sample random rows in dataframe
I am struggling to find the appropriate function that would return a specified number of rows picked up randomly without replacement from a data frame in R language? Can anyone help me out?
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How to decide font color in white or black depending on background color?
I want to show some images like this example
22 Answers
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Remove outline from select box in FF
Is it possible to remove the dotted line surrounding a selected item in a select element?
12 Answers
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How do I make an html link look like a button?
I'm using ASP.NET, some of my buttons just do redirects. I'd rather they were ordinary links, but I don't want my users to notice much difference in the appearance. I considered images wrapped by anchors, i.e. tags, but I don't want to have to fire up an image editor every time I change the text ...
Find XOR of all numbers in a given range
You are given a large range [a,b] where 'a' and 'b' can be typically between 1 and 4,000,000,000 inclusive. You have to find out the XOR of all the numbers in the given range.
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How do you match only valid roman numerals with a regular expression?
Thinking about my other problem , i decided I can't even create a regular expression that will match roman numerals (let alone a context-free grammar that will generate them)
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Why do Lua arrays(tables) start at 1 instead of 0?
I don't understand the rationale behind the decision of this part of Lua. Why does indexing start at 1? I have read (as many others did) this great paper . It seems to me a strange corner of a language that is very pleasant to learn and program. Don't get me wrong, Lua is just great but there has t...
How to grant remote access to MySQL for a whole subnet?
I can easily grant access to one IP using this code:
7 Answers
7
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What's the difference between a single precision and double precision floating point operation?
What is the difference between a single precision floating point operation and double precision floating operation?
11 Answ...