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How to efficiently count the number of keys/properties of an object in JavaScript?
...t only iterates through the object but also creates a whole new array with all its keys, so it completely fails at answering the question.
– GetFree
Jun 22 '12 at 14:28
43
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bash: mkvirtualenv: command not found
...
Solution 1:
For some reason, virtualenvwrapper.sh installed in /usr/bin/virtualenvwrapper.sh, instead of under /usr/local/bin.
The following in my .bash_profile works...
source "/usr/bin/virtualenvwrapper.sh"
export WORKON_HOME="/opt/virtual_env/"
My install seems to work fi...
How to load external webpage inside WebView
...
Thanks to this post, I finally found the solution. Here is the code:
import android.app.Activity;
import android.os.Bundle;
import android.webkit.WebResourceError;
import android.webkit.WebResourceRequest;
import android.webkit.WebView;
import androi...
Xcode variables
...mmand for the shell you're using) and build your project. This will output all of the environment variables that are available to you. You can use this in conjunction with the documentation to make sure you're getting the data that you expected.
– Ryan H.
Mar 9...
How to change MySQL data directory?
...r/mysql
# Stop MySQL before copying over files
service mysql stop
# Copy all files in default directory, to new one, retaining perms (-p)
cp -rp /var/lib/mysql/* /new/dir/for/mysql/
Edit the /etc/my.cnf file, and under [mysqld] add this line:
datadir=/new/dir/for/mysql/
If you are using CageF...
Clear the entire history stack and start a new activity on Android
... need to close the application then while starting Activity B from A just call finish() this will prevent android from storing Activity A in to the Backstack.eg for activity A is Loding/Splash screen of application.
Intent newIntent = new Intent(A.this, B.class);
startActivity(newIntent);
finish();...
How to step through Python code to help debug issues?
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Yes! There's a Python debugger called pdb just for doing that!
You can launch a Python program through pdb by using pdb myscript.py or python -m pdb myscript.py.
There are a few commands you can then issue, which are documented on the pdb page.
Some usef...
How to reorder data.table columns (without copying)
... 2 2
# [3,] 0.3297416 1 3
From ?setcolorder:
In data.table parlance, all set* functions change their input by reference. That is, no copy is made at all, other than temporary working memory, which is as large as one column.
so should be pretty efficient. See ?setcolorder for details.
...
Safe String to BigDecimal conversion
...0,000,000.999999999999999";
BigDecimal money = new BigDecimal(value.replaceAll(",", ""));
System.out.println(money);
Full code to prove that no NumberFormatException is thrown:
import java.math.BigDecimal;
public class Tester {
public static void main(String[] args) {
// TODO Auto-...
Why NSUserDefaults failed to save NSMutableDictionary in iOS?
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When do I need to release the loaded object? No alloc was called, so I would assume it is autorelased?
– Marc
Apr 16 '12 at 13:08
7
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