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What are the differences between numpy arrays and matrices? Which one should I use?
... here. Instead of performing fewer checks, using matrix*matrix requires an extra function call. So the advantage of using matrix is purely syntactic, not better performance.
– unutbu
Sep 18 '17 at 20:44
...
What is the difference between up-casting and down-casting with respect to class variable
...og.
Police Dog - Police Dog extends Pet Dog.
public class Dog{
public String getType () {
System.out.println("NormalDog");
return "NormalDog";
}
}
/**
* Pet Dog has an extra method dogName()
*/
public class PetDog extends Dog{
public String getType () {
System.ou...
How to use if - else structure in a batch file?
...taneously. In this case you can still use IF...ELSE IF construct, but with extra parentheses to avoid uncertainty for the next ELSE condition:
IF %F%==1 (IF %C%==1 (
::copying the file c to d
copy "%sourceFile1%" "%destinationFile1%" )
) ELSE IF %F%==1 (IF %C%==0 (
::moving the file e t...
Java Timestamp - How can I create a Timestamp with the date 23/09/2007?
...w Timestamp(time); giving error that no constructor like this which take a string value :(
– Bhanu Sharma
May 14 '14 at 13:02
...
How are Python's Built In Dictionaries Implemented?
... ...
For a 64 bit machine, this could save up to 16 bytes per key per extra dictionary.
Shared Keys for Custom Objects & Alternatives
These shared-key dicts are intended to be used for custom objects' __dict__. To get this behavior, I believe you need to finish populating your __dict__ be...
Efficiency of Java “Double Brace Initialization”?
...Just for reference, double brace initialization is the following:
List<String> list = new ArrayList<String>() {{
add("Hello");
add("World!");
}};
It looks like a "hidden" feature of Java, but it is just a rewrite of:
List<String> list = new ArrayList<String>() {
...
No == operator found while comparing structs in C++
...
@Xeo: memcmp fails with non-POD members (like std::string) and padded structures.
– fredoverflow
Apr 21 '11 at 8:07
16
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Custom HTTP headers : naming conventions
...orwarded-For" on the one hand, vs. (B) app developers passing app-specific strings to/from client and server. The spec only concerns itself with the former, (A). The question here is whether there are conventions for (B). There are. They involve grouping the parameters together alphabetically, and s...
Resolve build errors due to circular dependency amongst classes
...o handle the forward declarations. The only "disadvantage" would be in the extra files. I assume you always include a.fwd.h in a.h, to assure they stay in sync. The example code is missing where these classes are used. a.h and b.h will both need to be included since they won't function in isolatio...
How do you select a particular option in a SELECT element in jQuery?
... will match pieces of text; problematic if any of your option text is a substring of another option text.
– Ryan
Nov 3 '14 at 21:56
28
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