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MongoDB - Update objects in a document's array (nested updating)
...rue);
For your question #2, the answer is easier. To increment the total and the price of item_three in any document that contains "my_item_three," you can use the $inc operator on multiple fields at the same time. Something like:
db.bar.update( {"items.item_name" : {$ne : "my_item_three" }} ,
...
Why does Math.round(0.49999999999999994) return 1?
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Summary
In Java 6 (and presumably earlier), round(x) is implemented as floor(x+0.5).1 This is a specification bug, for precisely this one pathological case.2 Java 7 no longer mandates this broken implementation.3
The problem
0.5+0.49999999...
What is an MvcHtmlString and when should I use it?
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I stand corrected - actually the MvcHtmlString.Create method detects whether IHtmlString is available and dynamically creates the returned class to support it if it is: windowsitpro.com/article/net-framework/Encoding-and-Strings/...
Does Entity Framework Code First support stored procedures?
I've watched several presentations of EF Code First and haven't seen how EFCF works with stored procedures.
5 Answers
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Applying function with multiple arguments to create a new pandas column
I want to create a new column in a pandas data frame by applying a function to two existing columns. Following this answer I've been able to create a new column when I only need one column as an argument:
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How to form tuple column from two columns in Pandas
I've got a Pandas DataFrame and I want to combine the 'lat' and 'long' columns to form a tuple.
4 Answers
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Types in Objective-C on iOS
...G_MAX); // unsigned long long int
When run on an iPhone 3GS (iPod Touch and older iPhones should yield the same result) you get:
Primitive sizes:
The size of a char is: 1.
The size of short is: 2.
The size of int is: 4.
The size of long is: 4. ...
Reading file contents on the client-side in javascript in various browsers
...ince I originally wrote this answer, the File API has been proposed as a standard and implemented in most browsers (as of IE 10, which added support for FileReader API described here, though not yet the File API). The API is a bit more complicated than the older Mozilla API, as it is designed to sup...
Renaming table in rails
...n't going to work. Instead you'll have to create an instance of the class, and call the method on the instance, like this: Class.new.method.
[EDIT]
In this instance, ActiveRecord::ConnectionAdapters::SchemaStatements isn't even a class (as pointed out by cam), which means that you can't even create...
How to use Swift @autoclosure
...})
// "It's true"
If we omit the braces, we are passing in an expression and that's an error:
f(pred: 2 > 1)
// error: '>' produces 'Bool', not the expected contextual result type '() -> Bool'
@autoclosure creates an automatic closure around the expression. So when the caller writes an...