Object slicing refers to assignment by value of a sub-class instance to a super-class instance,thereby losing part of the information i.e. the sub-class specific data members are ignored.
Questions tagged [object-slicing]
220 questions
0
votes
2 answers
Using this slice my object
I have some difficulties using this, it seems to slice my derived class. This example will help me to explain my problem.
class A
{
A() {
OtherClass(*this);
}
virtual doSomething() = 0;
}
class B : public A
{
B() : A()…
Nitixx
- 48
- 6
0
votes
2 answers
Python - Array slicing
I have an assignment from my university. They asked me to analyse a slicing operation and explain it.
A = array([[1,2,3],[4,5,6],[7,8,9]])
A[0,arrange(3)<>0]
A[1,arrange(3)<>1]
A[2,arrange(3)<>2]
The operation to analyse is the following: A[k,…
BobaJ
- 1
0
votes
1 answer
How to solve this Object Slicing issue with GoogleMock
Below is one of the line in my method. Here i have to mock the method "findChild" and make "Chino::mock_Button" instance to be assigned to the "close_button". This is my requirement.
Chino::Button* close_button =…
Bharathi
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0
votes
3 answers
Function polymorphism with Reference Data Type
I have a queue that contains Objects of class Event.
std::priority_queue events;
But Event is just a superclass of actual events.
Lets assume we have following classes:
class Event{
public:
void Action(){
std::cout<<"do…
finaleblue
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- 4
0
votes
1 answer
ValueError: could not broadcast input array from shape (1,19) into shape (1,20)
I keep on getting this error when I am trying to do simple numpy array slicing. It's hard to describe this code but basically I have an image (binarised, by name and properties) and I have created a small box window (1x20), I am trying to loop…
Scott Alistair
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0
votes
1 answer
Object slicing when using CRTP
I am stuck with an object slicing problem when using CRTP. The following mock illustrates my problem.
#include
class CrtpGenr
{
};
template
class CrtpBase : public CrtpGenr
{
public:
static
auto…
vixiv
- 161
- 8
0
votes
1 answer
Object Slicing : Access dervied class methods from base class object
Edit :
The problem is in the GoFish.h file, in the constructor to
be specific, where it is trying to instantiate the players object.
The compiler throws the following error message : no member named 'noOfBooks' in 'Player'
GoFish() {players…
Luv
- 44
- 6
0
votes
2 answers
pandas, slice multi-index df with multiple conditions
This question is a continuation of pandas re-indexing with missing dates
I want to compute the sum of the values for the most recent 3 months (2015-12, 2015-11, 2015-10). If a stock doesn't have sufficient data i.e. has none,1 or 2 of the 3 months…
codingknob
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0
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0 answers
Inheritance or Object Slicing?
I've read up so much on this, and can't figure out why my Player object is losing its draw function.
Object class:
class Object {
public:
Object(){}
Object(Object* o){
o->draw();
}
virtual void…
MPenate
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0
votes
0 answers
How to divide a dataset according to a value in a column?
I have a pandas data frame with a column that represents dates as:
Name: ts_placed, Length: 13631, dtype: datetime64[ns]
It looks like this ( it was recoded using week as time unit):
0 42
1 44
2 44
3 41
4 43
5 45
6 …
Blue Moon
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0
votes
1 answer
Virtual method being called instead of derived method
i'm having trouble with an inherited function and i can't seem to figure out why it's behaving the way it is, and haven't been able to find an answer in other questions on SO.
I'm working on a small game and the inherited function is responsible for…
Felix Neijzen
- 37
- 8
0
votes
1 answer
numpy get 2d array where last dimension is indexed according to a 2d array
I did read on numpy indexing but I didn't find what I was looking for.
I have a 288*384 image, where each pixel can have a labelling in [0,15].
It is stored in a 3d (288,384,16)-shaped numpy array im.
With im[:,:,1], I can for example get the image…
maxbellec
- 16,093
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0
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2 answers
Calling child method
In my C++ project I have a class called Trap. A Trap is an NPC and an NPC is an Entity. Now I want to loop through all NPC's and do stuff with them. For example, I want a Trap to update. I do that in the following way.
for (vector::iterator it…
Ozitiho
- 346
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- 9
0
votes
2 answers
Class Slicing within Vector
I believe I have a slicing problem, and I am not sure how to fix it. I have summarized the issue from my actual program into the example below.
#include
#include
using namespace std;
class Base {
public:
void Use(void) {
…
halexh
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- 19
0
votes
2 answers
Why does slicing occur?
Please consider the following code:
Base b;
if (something)
b = DerivedA();
else
b = DerivedB();
It's well known that in such a case, 'slicing' occurs: In C++ we can't assign a variable of a base type an object of the derived type; the…
Aviv Cohn
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