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Assign multiple columns using := in data.table, by group
...t(dim(get(objectName))),by=objectName]. Trouble is that as.list has call overhead and also copies the small vector. If efficiency is a problem as number of groups rises then please let us know.
– Matt Dowle
May 21 '14 at 11:49
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What is the difference between object keys with quotes and without quotes?
...xchange format does require double quotes around identifiers (and does not allow single quotes).
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How did I get a value larger than 8 bits in size from an 8-bit integer?
...sible results for undefined behaviour is a valid consequence, there is actually no undefined behaviour in your code. What's happening is that the compiler thinks the behaviour is undefined, and optimises accordingly.
If c is defined as int8_t, and int8_t promotes to int, then c-- is supposed to per...
c# open a new form then close the current form?
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Steve's solution does not work. When calling this.Close(), current form is disposed together with form2. Therefore you need to hide it and set form2.Closed event to call this.Close().
private void OnButton1Click(object sender, EventArgs e)
{
this.Hide();
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Update parent scope variable in AngularJS
... Sorry I forgot about this question. I have accepted it because eventually I did manage to get it working with the help of this answer.
– Malcr001
Jun 13 '13 at 22:46
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How do I move a single folder from one Subversion repository to another repository?
...n repository named "project". I've come to the conclusion that it should really be kept under a separate Subversion repository named "project_docs".
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How to install grunt and how to build script with it
Hi I'm trying to install Grunt on Windows 7 64 bit. I have installed Grunt using commands
4 Answers
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Full Page
I have the example code below. This works fine with all browsers except for browsers on mobile devices.
5 Answers
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Bash conditionals: how to “and” expressions? (if [ ! -z $VAR && -e $VAR ])
...te easily handle empty strings. If that's what you want then you don't actually need the -z non-empty check:
pax> VAR=xyzzy
pax> if [[ -e $VAR ]] ; then echo yes ; fi
pax> VAR=/tmp
pax> if [[ -e $VAR ]] ; then echo yes ; fi
yes
In other words, just use:
if [[ -e "$var" ]] ; then
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Github: Import upstream branch into fork
...etween the branch in the upstream with the current local branch instead of allowing the creation of a new local branch. Any ideas?
– mMontu
Sep 6 '13 at 12:14
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