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Is multiplication and division using shift operators in C actually faster?
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Short answer: Not likely.
Long answer:
Your compiler has an optimizer in it that knows how to multiply as quickly as your target processor architecture is capable. Your best bet is to tell the compiler your intent clearly (i.e. i*2 rather than i << 1) and let it...
Emacs, switch to previous window
...w many windows to move by inserting a numeric argument between C-u and the command, as in C-u 2 C-x o. (C-- is a shortcut for C-u - 1)
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My Git repository is in the wrong root directory. Can I move it? (../ instead of ./)
Somehow when I git init ed my latest project a month or so ago I ran the command in the directory one directory higher than the root of my project.
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How do you convert epoch time in C#?
...Seconds to .AddMilliseconds. You will need to know whether your number is coming from Seconds or Milliseconds in order to get the correct result. So for instance the following date: 1406310305188 (July 25 2014). epochconverter.com will also let you check your conversion results.
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SVN+SSH, not having to do ssh-add every time? (Mac OS)
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Maybe someone has an equivalent command for other environments? mysysgit's ssh-add doesn't accept the -K argument, either
– Blake
Sep 5 '14 at 7:43
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How do I auto-hide placeholder text upon focus using css or jquery?
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not working. stackblitz.com/edit/angular-jd2l6y-frudzk?file=app/…
– its me
Mar 20 '18 at 10:37
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How can I test that a value is “greater than or equal to” in Jasmine?
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What is the purpose of wrapping whole Javascript files in anonymous functions like “(function(){ … }
...)! So pretty similar to a class definition. To understand this better, I recommend the following links for some further reading:
Namespacing your Javascript
Private members in Javascript (by Douglas Crockford)
EDIT
I forgot to mention. In that final (), you can pass anything you want inside. Fo...
How does one reorder columns in a data frame?
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Your dataframe has four columns like so df[,c(1,2,3,4)].
Note the first comma means keep all the rows, and the 1,2,3,4 refers to the columns.
To change the order as in the above question do df2[,c(1,3,2,4)]
If you want to output this file as a csv, do write.csv(df2, file="somedf.csv")
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See also the following question: stackoverflow.com/questions/758688/…
– GDP2
Aug 26 at 5:17
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