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How to prevent ifelse() from turning Date objects into numeric objects
I am using the function ifelse() to manipulate a date vector. I expected the result to be of class Date , and was surprised to get a numeric vector instead. Here is an example:
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How can one see content of stack with GDB?
...rame info
To read the memory at given addresses you should take a look at x
x/x $esp for hex x/d $esp for signed x/u $esp for unsigned etc. x uses the format syntax, you could also take a look at the current instruction via x/i $eip etc.
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Why does Double.NaN==Double.NaN return false?
... returns false and any != comparison involving NaN returns true, including x!=x when x is NaN.
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Awaiting multiple Tasks with different results
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@Sergey: The tasks begin executing immediately. E.g., catTask is already running by the time it's returned from FeedCat. So either approach will work - the only question is whether you want to await them one at a time or all together. The error handli...
join list of lists in python [duplicate]
Is the a short syntax for joining a list of lists into a single list( or iterator) in python?
15 Answers
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How to make rounded percentages add up to 100%
...function foo(l, target) {
var off = target - _.reduce(l, function(acc, x) { return acc + Math.round(x) }, 0);
return _.chain(l).
sortBy(function(x) { return Math.round(x) - x }).
map(function(x, i) { return Math.round(x) + (off > i) - (i >= (l.length + off)) })....
Ruby's ||= (or equals) in JavaScript?
I love Ruby's ||= mechanism. If a variable doesn't exist or is nil , then create it and set it equal to something:
6 Ans...
Why does this method print 4?
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I think the others have done a good job at explaining why cnt > 0, but there's not enough details regarding why cnt = 4, and why cnt varies so widely among different settings. I will attempt to fill that void here.
Let
X be the total stack size
M be the stack sp...
What does 'predicate' mean in the context of computer science? [duplicate]
Specifically I've seen it used in the context of text filtering. As if "predicate" == "filter criteria".
7 Answers
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What's the @ in front of a string in C#?
...ored.
So "C:\\Users\\Rich" is the same as @"C:\Users\Rich"
There is one exception: an escape sequence is needed for the double quote. To escape a double quote, you need to put two double quotes in a row. For instance, @"""" evaluates to ".
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