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
1
vote
3 answers
Average over time series data with custom time slice window
I am working with some tennis ranking data in R, that gives the evolution of tennis rankings over time of all the players on the ATP tour.
An example of the data I am using can be found here, giving the rankings data from 2000's:…
ap21
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1 answer
Why is my exception sliced to base class if I catch it with reference to base class?
So I've written a small C++ class as follows:
class bad_hmean : public std::logic_error {
const char *nature_;
char *what_;
public:
bad_hmean(const char *fname);
~bad_hmean() { delete[] what_; }
const char *what() { return…
Nikola Vugdelija
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1
vote
2 answers
Limit on Number of cart-products
I'd like to set a limit on the number of products that can be added on a cart.
--Case scenario: Assuming delivery-resource scarcity, I don't want users to add more than 5 products at a time. (The quantity of same product can, however, be…
Magere
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1
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7 answers
set the base object of derived object?
This is a basic concept question. If I have a class that Derived that inherits from Base, and I instantiate a new Derived object, can I set it's Base object to a specific Base object of my choosing so that all calls base class methods are redirected…
user487100
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7 answers
Removing set of characters from the end of the string
I want to remove @email.com from this string and also as such that even if the "myemail" part is changed the code should still work
I did this:
email = "myemail@email.com"
a = a.replace(a[-10:-1],'')
print(a)
Output:
myemailm
I wanted to remove…
Harsh
- 126
- 6
1
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2 answers
Return reference to sliced object (supertype)
Consider the following classes:
class Coord
{
public:
double _x, _y;
Coord(double x, double y)
{
_x = x;
_y = y;
}
};
class NamedPoint : public Coord
{
public:
int _id;
NamedPoint(int id, double x, double…
jedwards
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1 answer
what does k[:0] means, if k is an empty list
I want to know what does list[:0] means. In the following code what it is doing?
LETTERS = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
k=[]
while len(k) < 20:
for i in LETTERS:
k[:0] = i
print(k)
# k = ['Z', 'Y', 'X', 'W', 'V', 'U', 'T', 'S', 'R',…
Rick Torreto
- 25
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1
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1 answer
Slicing pandas dataframe based on rearranged duplicates (or how to drop rearranged duplicates)
I have a big dataframe with the format
col1 col2 val1 val2
[0]A B 0.8 0.1
[1]B A 0.8 0.1
[2]A C 0.3 0.9
[3]A D 0.2 0.8
[4]D A 0.2 0.8
As you can see, some…
Sos
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0 answers
Equivalent to R " -c()" syntax to exclude rows / columns for Python numpy array
I'm trying to find an efficient way to explicitly exclude a list of columns from a numpy array. I'm aware that in R by placing the "minus" sing before c() you can specify what columns not to include from a data frame
I have tried using "~" before…
user11449055
1
vote
2 answers
Virtual Table and Object Slicing
In object slicing, when a derived class object is copied to a Base class object, does the _vptr of Derived class also get copied to _vptr of Base class, like other members of class Base? If not, why?
class Base {
public :
virtual void Display()…
Suraj Kottayi
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- 5
1
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3 answers
How to do python style string slicing in c++
Is it possible to implement a method through which I can do slicing in C++ using : operator.
For example,I define a C-style string as shown below:
char my_name[10] {"InAFlash"};
Can I implement a function or override any internal method to do the…
rawwar
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1
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1 answer
Array of Pointers to Different Derived Classes
I'm working on the core for a family of microprocessor units based off of the ATMEGA328P. I have a base class and two derived classes that I need to store mixed together in an array. I have the following:
// base class
class Channel {
virtual…
Phillip McMullen
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1
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3 answers
C++ Constructor member initializer lists, Object Slicing
I have two classes
class A {
public:
virtual void doStuff() = 0;
};
class B : public A {
int x;
public:
virtual void doStuff() override { x = x*2;} //just example function
};
And another class that modify and use data from the…
quetzalfir
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1
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2 answers
String slicing big O
for i in range(n):
print("HelloWorld"[i:])
Is this O(n) or should I count the slicing as running over the characters of "HelloWorld"?
Also, when I compare two strings s1==s2 does this operation run over each letter in s1 and compare it with…
Programmingfreak
- 61
- 9
1
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2 answers
Member variables and object slicing
This answer suggests that object slicing in vectors can be overcome with the use of pointers. From my testing, this is true when working with variables shared between the base and derived classes. For example, given these classes:
class Base…
Nullsrc
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