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Simultaneously merge multiple data.frames in a list
... issue here is that each data.frame differs in terms of the number of rows and columns, but they all share the key variables (which I've called "var1" and "var2" in the code below). If the data.frames were identical in terms of columns, I could merely rbind , for which plyr's rbind.fill would...
How can I get a count of the total number of digits in a number?
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I'm afraid ceil(log10(10)) = ceil(1) = 1, and not 2 as it should be for this question!
– ysap
Dec 19 '10 at 18:08
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Formula to determine brightness of RGB color
...GB values. I know it can't be as simple as adding the RGB values together and having higher sums be brighter, but I'm kind of at a loss as to where to start.
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Maximum Java heap size of a 32-bit JVM on a 64-bit OS
... OS, given that 32-bit OSes have a maximum addressable memory size of 4GB, and that the JVM's max heap size depends on how much contiguous free memory can be reserved.
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count (non-blank) lines-of-code in bash
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cat foo.c | sed '/^\s*$/d' | wc -l
And if you consider comments blank lines:
cat foo.pl | sed '/^\s*#/d;/^\s*$/d' | wc -l
Although, that's language dependent.
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How is Docker different from a virtual machine?
I keep rereading the Docker documentation to try to understand the difference between Docker and a full VM. How does it manage to provide a full filesystem, isolated networking environment, etc. without being as heavy?
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Where are environment variables stored in registry?
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You don't need to restart. Just kill Explorer.exe and bring it back alive. It's the parent process for e.g. cmd.exe (when started from the Start menu)
– Cristian Diaconescu
Dec 8 '12 at 1:04
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Get name of current script in Python
...less there. It is set by the import implementation, so if you use a non-standard import mechanism it might also be unset.
– Sven Marnach
May 3 '13 at 19:18
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List of lists changes reflected across sublists unexpectedly
...(3)]
which will reevaluate [1]*4 each time instead of evaluating it once and making 3 references to 1 list.
You might wonder why * can't make independent objects the way the list comprehension does. That's because the multiplication operator * operates on objects, without seeing expressions. Wh...
Hidden features of mod_rewrite
...of it work. As a result I've compiled a few notes on common functionality, and perhaps a few annoying nuances.
8 Answers
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