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mongodb group values by multiple fields
... $slice just off the basic aggregation result. For "large" results, run parallel queries instead for each grouping ( a demonstration listing is at the end of the answer ), or wait for SERVER-9377 to resolve, which would allow a "limit" to the number of items to $push to an array.
db.books.aggregate(...
javac not working in windows command prompt
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ah yes, all i had to do was re-open the command prompt and it worked fine, thanks!
– Domenic
Nov 5 '09 at 6:02
1
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Create a CSS rule / class with jQuery at runtime
Usually I have a CSS file which has the following rule:
21 Answers
21
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Xcode 5.1 - No architectures to compile for (ONLY_ACTIVE_ARCH=YES, active arch=x86_64, VALID_ARCHS=i
...from the workspace in the left pane of Xcode and close Xcode.
Run "pod install" from the command line to recreate the "Pods" project.
Re-open Xcode and make sure "Build Active Architecture Only" is set to "No" in the build settings of both the "Pods" project and your own project.
Clean and build.
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Can I extend a class using more than 1 class in PHP?
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Answering your edit :
If you really want to fake multiple inheritance, you can use the magic function __call().
This is ugly though it works from class A user's point of view :
class B {
public function method_from_b($s) {
echo $s;
}
}
c...
Why does isNaN(“ ”) (string with spaces) equal false?
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You should try NaN===NaN or NaN==NaN;-) I don't know if all this means the javascript engine is wacky or that javascript is bad for wacky programmers though.
– KooiInc
May 5 '09 at 22:01
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从源代码剖析Mahout推荐引擎 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
从源代码剖析Mahout推荐引擎前言Mahout框架中cf.taste包实现了推荐算法引擎，它提供了一套完整的推荐算法工具集，同时规范了数据结构，并标准化了程序开发过程。应用推...前言
Mahout框架中cf.taste包实现了推荐算法引擎，它提供...
undefined reference to `__android_log_print'
...sary. Please accept the other answer instead.
– Jeff Allen
Jun 21 '13 at 11:23
5
If using the new...
MySql server startup error 'The server quit without updating PID file '
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Did you follow the instructions from brew install mysql?
Set up databases to run AS YOUR USER ACCOUNT with:
For mysql 5.x:
unset TMPDIR
mysql_install_db --verbose --user=`whoami` --basedir="$(brew --prefix mysql)" --datadir=/usr/local/var/mysql --tmpdir=/tmp
To set...
Rails - Nested includes on Active Records?
I have a list of events that I fetch.
I'm trying to include every user associated to this event and every profile associated to each user. The Users get included but not their profiles.
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