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How do I dump an object's fields to the console?
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Using introspection is part of the fun of Ruby. It's often useful to subtract an Object's instance_methods from the class' in question to get the methods that are unique: (String.instance_methods - Object.instance_methods).sort
– the Tin ...
Numbering rows within groups in a data frame
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Use ave, ddply, dplyr or data.table:
df$num <- ave(df$val, df$cat, FUN = seq_along)
or:
library(plyr)
ddply(df, .(cat), mutate, id = seq_along(val))
or:
library(dplyr)
df %>% group_by(cat) %>% mutate(id = row_number())
or (the most memory efficient, as it assigns by reference w...
How do I edit the Visual Studio templates for new C# class/interface?
... Studio 12.0\Common7\IDE\ItemTemplates\CSharp\Code\1033\WebClass\Class.cs. Then run devenv.exe /installvstemplates.
– J. Andrew Laughlin
Sep 23 '14 at 20:19
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Parse large JSON file in Nodejs
...String(); // when data is read, stash it in a string buffer
pump(); // then process the buffer
});
function pump() {
var pos;
while ((pos = buf.indexOf('\n')) >= 0) { // keep going while there's a newline somewhere in the buffer
if (pos == 0) { // if there's more than one ne...
Initializing select with AngularJS and ng-repeat
...n empty value in when initialized.
If you want to select a default option then you can probably can set it on the scope in the controller
$scope.filterCondition.operator = "your value here";
If you want to an empty option placeholder, this works for me
<select ng-model="filterCondition.oper...
Best way to resolve file path too long exception
...red folder with a shorter path (you may have to run it as administrator).
Then type with relative or absolute paths:
mklink ShortPath\To\YourLinkedSolution C:\Path\To\Your\Solution /D
And then start the Solution from the shorter path. The advantage here is: You don't have to move anything.
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How do I make the method return type generic?
... name, Class<T> type) {
return type.cast(friends.get(name));
}
Then call it as such:
jerry.callFriend("spike", Dog.class).bark();
jerry.callFriend("quacker", Duck.class).quack();
This code has the benefit of not generating any compiler warnings. Of course this is really just an update...
This app won't run unless you update Google Play Services (via Bazaar)
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I used Titanium Backup to backup my Asus Eee Pad Transformer (TF101) and then grabbed the com.android.vending and the com.google.android.gms APK files from the backup.
I installed these on an emulator configured with platform: 4.1.2, API Level: 16, CPU Intel/Atom x86) and my Google Maps V2 applic...
Using Caps Lock as Esc in Mac OS X
...PCKeyboardHack).
First, go into the System Preferences, choose Keyboard, then the Keyboard Tab (first tab), and click Modifier Keys:
In the popup dialog set Caps Lock Key to No Action:
2) Now, click here to download Seil and install it:
3) After the installation you will have a new Appli...
What is the coolest thing you can do in
...ce scripting is done with JavaScript (which is planned in the near future) then the decline of VB will be a sure thing.
– Evan Plaice
Sep 7 '11 at 23:34
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