Sponsored Content
Top Forums Programming How to make a function friend to both base and derived class Post 302200667 by mcaramel on Thursday 29th of May 2008 07:11:28 PM
Old 05-29-2008
I'm curious to know why placing the friendship declaration on top makes a difference.
What does 'friends are not part of the class' actually means?

Thanks a lot,
thanks,
Michele
 

8 More Discussions You Might Find Interesting

1. HP-UX

How to make a loop base on reading a file?

Need help on making a loop script base on what is inside a file... File to read: List.txt List.txt contains below w/c are file name as well: SAMPLEa SAMPLEb SAMPLEc SAMPLEd SAMPLEe SAMPLEf . . . Want to make a loop that will manipulate those that are inside the file.txt w/c are... (3 Replies)
Discussion started by: JohnBalayo
3 Replies

2. Programming

Please help debug this friend class in C++

Please help check an old code: #include <iostream> using namespace std; template <class C> class List { //Linked list of C. template<class U> friend class ListItr; private: class ListEl { public: C val; ListEl* next; ListEl(const C& s, ListEl* n) : val(s) { next = n;} };... (0 Replies)
Discussion started by: learncode
0 Replies

3. Programming

Base class's variables not accessible????

Hi friends, The derived class cannot access the base class's variables in my program. You can have a look at my code, I am actually using class templates. #include <iostream> using namespace std; template <class T> class Sum { friend void Check(Sum &s, T a, T b) { T x,... (2 Replies)
Discussion started by: gabam
2 Replies

4. Programming

C++ compilation error when I use predicate friend function in the std::sort()

Hi, Can anyone tell me why the following program is giving compiler error when I use a friend function of a class as the comparison predicate for the third parameter of std::sort() algorithm? How to correct it, keep the 'friend' intact? #include <iostream> #include <vector> #include <list>... (1 Reply)
Discussion started by: royalibrahim
1 Replies

5. Programming

Size of Derived class, upon virtual base class inheritance

I have the two class definition as follows. class A { public: int a; }; class B : virtual public A{ }; The size of class A is shown as 4, and size of class B is shown as 16. Why is this effect ?. (2 Replies)
Discussion started by: techmonk
2 Replies

6. Programming

Size of derived class, in case of multiple inheritance

Why, here the size of class 'Derived' is 8 ? class Base1 { public: virtual void f() { } }; class Base2 { public: virtual void f() { } }; class Derived : public Base1, Base2 { public: virtual void f() { } }; (1 Reply)
Discussion started by: techmonk
1 Replies

7. Programming

C++ : Base class member function not accessible from derived class

Hello All, I am a learner in C++. I was testing my inheritance knowledge with following piece of code. #include <iostream> using namespace std; class base { public : void display() { cout << "In base display()" << endl; } void display(int k) {... (2 Replies)
Discussion started by: anand.shah
2 Replies

8. Shell Programming and Scripting

Derived both lines base on pattern

Dear All, I have a requests to retrieve all lines if second line last columns meets certain criteria. Here is the output of the result Table: DSSBDW.DA_MASK_CLK_AR 120908 0 86 86 - 1934528 0 70 100 -*- Table: DSSBDW.DA_MASK_CLK_IP 310657 22030 143 185 - 5281169 7 88 77 *-* Table:... (5 Replies)
Discussion started by: ckwan123
5 Replies
pnmpsnr(1)                                                    General Commands Manual                                                   pnmpsnr(1)

NAME
pnmpsnr - compute the difference between two portable anymaps SYNOPSIS
pnmpsnr [pnmfile1] [pnmfile2] DESCRIPTION
Reads two PBM, PGM, or PPM files, or PAM equivalents, as input. Prints the peak signal-to-noise ratio (PSNR) difference between the two images. This metric is typically used in image compression papers to rate the distortion between original and decoded image. If the inputs are PBM or PGM, pnmpsnr prints the PSNR of the luminance only. Otherwise, it prints the separate PSNRs of the luminance, and chrominance (Cb and Cr) components of the colors. The PSNR of a given component is the ratio of the mean square difference of the component for the two images to the maximum mean square difference that can exist betwee any two images. It is expressed as a decibel value. The mean square difference of a component for two images is the mean square difference of the component value, comparing each pixel with the pixel in the same position of the other image. For the purposes of this computation, components are normalized to the scale [0..1]. The maximum mean square difference is identically 1. So the higher the PSNR, the closer the images are. A luminance PSNR of 20 means the mean square difference of the luminances of the pixels is 100 times less than the maximum possible difference, i.e. 0.01. SEE ALSO
pnm(5) 04 March 2001 pnmpsnr(1)
All times are GMT -4. The time now is 07:25 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy