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Finding the index of elements based on a condition using python list comprehension
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In Python, you wouldn't use indexes for this at all, but just deal with the values—[value for value in a if value > 2]. Usually dealing with indexes means you're not doing something the best way.
If you do need an API similar to Matlab's, you would use numpy, a packag...
What Makes a Good Unit Test? [closed]
...ng lots of automated tests and that you also have run into some common pitfalls when unit testing.
18 Answers
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Getting hold of the outer class object from the inner class object
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Here's the example:
// Test
public void foo() {
C c = new C();
A s;
s = ((A.B)c).get();
System.out.println(s.getR());
}
// classes
class C {}
class A {
public class B extends C{
A get() {return A.this;}
}
public String getR() {
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Iterating over Java collections in Scala
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As of Scala 2.8, all you have to do is to import the JavaConversions object, which already declares the appropriate conversions.
import scala.collection.JavaConversions._
This won't work in previous versions though.
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Putting an if-elif-else statement on one line?
...but only for expressions, not for statements:
>>> a = "Hello" if foo() else "Goodbye"
Edit:
Your revised question now shows that the three statements are identical except for the value being assigned. In that case, a chained ternary operator does work, but I still think that it's less r...
/usr/lib/libstdc++.so.6: version `GLIBCXX_3.4.15' not found
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I'm compiling gcc 4.6 from source, and apparently
sudo make install
didn't catch this one. I dug around and found
gcc/trunk/x86_64-unknown-linux-gnu/libstdc++-v3/src/.libs/libstdc++.so.6.0.15
I copied it in to /usr/lib and redirected libstdc++.so.6 to point to the new one, and now e...
Best way to implement Enums with Core Data
...to assign a type property to the entity? In other words, I have an entity called Item with an itemType property that I want to be bound to an enum, what is the best way of going about this.
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map vs. hash_map in C++
...tied to that key.
map is implemented as a balanced binary search tree (usually a red/black tree).
An unordered_map should give slightly better performance for accessing known elements of the collection, but a map will have additional useful characteristics (e.g. it is stored in sorted order, which...
Add a column with a default value to an existing table in SQL Server
...ed for Existing Records.
If your Column is NOT NULL, then it will automatically use the Default Value
for all Existing Records, whether you specify WITH VALUES or not.
How Inserts work with a Default-Constraint:
If you insert a Record into SomeTable and do not Specify SomeCol's value, then it...
python location on mac osx
...e python on osx. I do not know if the previous owner of the laptop has installed macpython using macport. And I remembered that osx has an builtin version of python. I tried using type -a python and the result returned
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