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What is a NullReferenceException, and how do I fix it?
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What is the cause?
Bottom Line
You are trying to use something that is null (or Nothing in VB.NET). This means you either set it to null, or you never set it to anything at all.
Like anything else, null gets passed around. If it is null in meth...
Bitwise operation and usage
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Bitwise operators are operators that work on multi-bit values, but conceptually one bit at a time.
AND is 1 only if both of its inputs are 1, otherwise it's 0.
OR is 1 if one or both of its inputs are 1, otherwise it's 0.
X...
List vs tuple, when to use each? [duplicate]
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There's a strong culture of tuples being for heterogeneous collections, similar to what you'd use structs for in C, and lists being for homogeneous collections, similar to what you'd use arrays for. But I've never quite squared this with the mutability issue ...
Chained method calls indentation style in Python [duplicate]
... line continuation character is preferred to open parentheses.
ShortName.objects.distinct() \
.filter().values() # looks better
The need for this style becomes more obvious as method names get longer and as methods start taking arguments:
return some_collection.get_objects(locator=...
Accessing Object Memory Address
When you call the object.__repr__() method in Python you get something like this back:
9 Answers
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Reverse Y-Axis in PyPlot
I have a scatter plot graph with a bunch of random x, y coordinates. Currently the Y-Axis starts at 0 and goes up to the max value. I would like the Y-Axis to start at the max value and go up to 0.
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Convert String array to ArrayList [duplicate]
...a.util.Arrays;
import java.util.List;
import java.util.ArrayList;
public class StringArrayTest {
public static void main(String[] args) {
String[] words = {"ace", "boom", "crew", "dog", "eon"};
List<String> wordList = Arrays.asList(words);
for (String e : w...
Lambda Expression and generic method
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You can't use a lambda expression for a functional interface, if the method in the functional interface has type parameters. See section §15.27.3 in JLS8:
A lambda expression is compatible [..] with a target type T if T is a functional int...
Why does ReSharper tell me “implicitly captured closure”?
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The warning tells you that the variables end and start stay alive as any of the lambdas inside this method stay alive.
Take a look at the short example
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
int i = 0;
Random g = new Random...
Determining memory usage of objects? [duplicate]
I'd like to work out how much RAM is being used by each of my objects inside my current workspace. Is there an easy way to do this?
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