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Clean ways to write multiple 'for' loops
.../ ...
}
(or just:
for ( auto& elem: m ) {
}
if you have C++11.)
And if you need the three indexes during such iterations, it's
possible to create an iterator which exposes them:
class Matrix3D
{
// ...
class iterator : private std::vector<int>::iterator
{
Matri...
Get current time in seconds since the Epoch on Linux, Bash
...e , but in seconds since 1970 instead of the current date, hours, minutes, and seconds.
7 Answers
...
OrderBy descending in Lambda expression?
...
As Brannon says, it's OrderByDescending and ThenByDescending:
var query = from person in people
orderby person.Name descending, person.Age descending
select person.Name;
is equivalent to:
var query = people.OrderByDescending(person =>...
How do I replace a character at a particular index in JavaScript?
I have a string, let's say Hello world and I need to replace the char at index 3. How can I replace a char by specifying a index?
...
Summarizing multiple columns with dplyr? [duplicate]
... a bit with the dplyr-syntax. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R.
...
Method call if not null in C#
...ke();
or:
obj?.SomeMethod();
The ?. is the null-propagating operator, and will cause the .Invoke() to be short-circuited when the operand is null. The operand is only accessed once, so there is no risk of the "value changes between check and invoke" problem.
===
Prior to C# 6, no: there is no...
Correct way to check if a type is Nullable [duplicate]
...sting disagreement between the specification (your link in the first line) and the actual behavior. For your propertyType object from the last line is a counter-example. What I mean is that Nullable.GetUnderlyingType(propertyType) does not return null (it returns your T) although propertyType is an ...
How to deserialize xml to object [duplicate]
...If you want to read a text file you should load the file into a FileStream
and deserialize this.
using (FileStream fileStream = new FileStream("<PathToYourFile>", FileMode.Open))
{
StepList result = (StepList) serializer.Deserialize(fileStream);
}
...
Can you do a partial checkout with Subversion?
If I had 20 directories under trunk/ with lots of files in each and only needed 3 of those directories, would it be possible to do a Subversion checkout with only those 3 directories under trunk?
...
How to Deserialize XML document
...entAttribute labels to XmlElement because in the xml the StockNumber, Make and Model values are elements, not attributes. Also I removed the reader.ReadToEnd(); (that function reads the whole stream and returns a string, so the Deserialize() function couldn't use the reader anymore...the position w...