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Find an item in List by LINQ?
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If you want the index of the element, this will do it:
int index = list.Select((item, i) => new { Item = item, Index = i })
.First(x => x.Item == search).Index;
// or
var tagged = list.Select((item, i) => new { Item = item, Index = i });
int index = (fro...
How can I read SMS messages from the device programmatically in Android?
...esult to prevent exception
do {
String msgData = "";
for(int idx=0;idx<cursor.getColumnCount();idx++)
{
msgData += " " + cursor.getColumnName(idx) + ":" + cursor.getString(idx);
}
// use msgData
} while (cursor.moveToNext());
} else {
// em...
Calculate size of Object in Java [duplicate]
...getObjectSize(o);
}
}
Use getObjectSize:
public class C {
private int x;
private int y;
public static void main(String [] args) {
System.out.println(ObjectSizeFetcher.getObjectSize(new C()));
}
}
Source
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Jackson overcoming underscores in favor of camel-case
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You can configure the ObjectMapper to convert camel case to names with an underscore:
objectMapper.setPropertyNamingStrategy(PropertyNamingStrategy.SNAKE_CASE);
Or annotate a specific model class with this annotation:
@JsonNaming(PropertyNamingStrategy.SnakeC...
Applying a function to every row of a table using dplyr?
...e is increasingly not recommended, although lots of people seem to find it intuitive. Do yourself a favour and go through Jenny Bryan's Row-oriented workflows in R with the tidyverse material to get a good handle on this topic.
The most straightforward way I have found is based on one of Hadley's e...
How set background drawable programmatically in Android
...dy); is correct.
Another way to achieve it is to use the following:
final int sdk = android.os.Build.VERSION.SDK_INT;
if(sdk < android.os.Build.VERSION_CODES.JELLY_BEAN) {
layout.setBackgroundDrawable(ContextCompat.getDrawable(context, R.drawable.ready) );
} else {
layout.setBackground(C...
How do I expand a tuple into variadic template function's arguments?
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Here's my code if anyone is interested
Basically at compile time the compiler will recursively unroll all arguments in various inclusive function calls <N> -> calls <N-1> -> calls ... -> calls <0> which is the last one and th...
Are Exceptions in C++ really slow
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You can never claim about performance unless you convert the code to the assembly or benchmark it.
Here is what you see: (quick-bench)
The error code is not sensitive to the percentage of occurrence. Exceptions have a little bit overhead as long as they are never thrown. ...
Combine two ActiveRecord::Relation objects
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Relation objects can be converted to arrays. This negates being able to use any ActiveRecord methods on them afterwards, but I didn't need to. I did this:
name_relation = first_name_relation + last_name_relation
Ruby 1.9, rails 3.2
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How to sum up an array of integers in C#
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Provided that you can use .NET 3.5 (or newer) and LINQ, try
int sum = arr.Sum();
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