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Does pandas iterrows have performance issues?

... Generally, iterrows should only be used in very, very specific cases. This is the general order of precedence for performance of various operations: 1) vectorization 2) using a custom cython routine 3) apply a) reductions tha...
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How to append a newline to StringBuilder

... @tuscland - Why not just use System.lineSeparator() all the time? Why is '\n' a better option as default? – RyanfaeScotland Jun 3 '15 at 15:46 ...
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How do you match only valid roman numerals with a regular expression?

...0,3})$ Breaking it down, M{0,4} specifies the thousands section and basically restrains it to between 0 and 4000. It's a relatively simple: 0: <empty> matched by M{0} 1000: M matched by M{1} 2000: MM matched by M{2} 3000: MMM matched by M{3} 4000: MMMM matched by M...
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Some font-size's rendered larger on Safari (iPhone)

...blem you're describing centers around the fact that Mobile Safari automatically scales text if it thinks the text will render too small. You can get around this with the CSS property -webkit-text-size-adjust. Here's a sample of how to apply this to your body, just for the iPhone: @media screen and...
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Linq: What is the difference between Select and Where

...rable<A> in, IEnumerable<A> out Select returns something for all items in the source (projection / transformation). That something might be the items themselves, but are more usually a projection of some sort. -> IEnumerable<A> in, IEnumerable<B> out ...
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Setting mime type for excel document

... edited Feb 22 at 1:46 Callum Watkins 2,22222 gold badges2323 silver badges4040 bronze badges answered Dec 26 '09 at 19:44 ...
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How to sort a HashSet?

... Add all your objects to the TreeSet, you will get a sorted Set. Below is a raw example. HashSet myHashSet = new HashSet(); myHashSet.add(1); myHashSet.add(23); myHashSet.add(45); myHashSet.add(12); TreeSet myTreeSet = new TreeS...
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How to make graphics with transparent background in R using ggplot2?

...# for the inside of the boxplot ) Fastest way is using using rect, as all the rectangle elements inherit from rect: p <- p + theme( rect = element_rect(fill = "transparent") # all rectangles ) p More controlled way is to use options of theme: p <- p + theme( ...
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Change the name of a key in dictionary

...>>> dictionary['ONE'] = dictionary.pop(1) Traceback (most recent call last): File "<input>", line 1, in <module> KeyError: 1 share | improve this answer | ...
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Android add placeholder text to EditText

... Thanks! I didn't know what they call it in android, I just know that on iOS it's called placeholder. – Mona Nov 22 '11 at 4:24 40 ...