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When to use IMG vs. CSS background-image?

...ze. Use IMG for multiple overlay images in IE6. Use IMG with a z-index in order to stretch a background image to fill its entire window.Note, this is no longer true with CSS3 background-size; see #6 below. Using img instead of background-image can dramatically improve performance of animations ove...
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data.table vs dplyr: can one do something well the other can't or does poorly?

...ese aspects to provide a comprehensive answer/comparison (in no particular order of importance): Speed, Memory usage, Syntax and Features. My intent is to cover each one of these as clearly as possible from data.table perspective. Note: unless explicitly mentioned otherwise, by referring to dpl...
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Storing money in a decimal column - what precision and scale?

...However, rather than a one-size-fits-all approach, some research may be in order. Ask your designer or domain expert about accounting rules which may be applicable: GAAP, EU, etc. I vaguely recall some EU intra-state transfers with explicit rules for rounding to five decimal places, therefore using ...
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What does the question mark operator mean in Ruby?

...ruby 1.9: "F".ord Also notice that ?F will return the string "F", so in order to make the code shorter, you can also use ?F.ord in Ruby 1.9 to get the same result as "F".ord. share | improve this...
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What is the difference between LL and LR parsing?

...ponds to Reverse Polish Notation. The difference between PN and RPN is the order of traversing the binary tree of the equation: + 1 * 2 3 // Polish (prefix) expression; pre-order traversal. 1 2 3 * + // Reverse Polish (postfix) expression; post-order traversal. According to Haberman, this ill...
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python max function using 'key' and lambda expression

...t-2-0ce0a02693e4>", line 1, in <module> max(lis) TypeError: unorderable types: int() > str() But this works, as we are comparing integer version of each object: >>> max(lis, key=lambda x: int(x)) # or simply `max(lis, key=int)` '111' ...
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Sorting a list using Lambda/Linq to objects

...n direction) { if (direction == SortDirection.Ascending) list = list.OrderBy(sorter); else list = list.OrderByDescending(sorter); } Now you can specify the field to sort when calling the Sort method. Sort(ref employees, e => e.DOB, SortDirection.Descending); ...
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How to fix “Headers already sent” error in PHP

... Unintentional: Whitespace before <?php or after ?> The UTF-8 Byte Order Mark specifically Previous error messages or notices Intentional: print, echo and other functions producing output Raw <html> sections prior <?php code. Why does it happen? To understand why header...
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INSERT INTO vs SELECT INTO

...h many columns with similar structures to other tables and then edit it in order to save time. share | improve this answer | follow | ...
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Where are my postgres *.conf files?

...tart) # - When to Log - #client_min_messages = notice # values in order of decreasing detail: # debug5 # debug4 # debug3 # debug2 # debug1 # log ...