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i am implementing fuzzy logic for allignment of my robot drive so that it will drive smoothly i am implementing an IEEE research paper in which they have used it and that i am implementing .
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Good day, I am from Turkey. MFC is in its start on. Can you help me I have a problem. I want to do a small project. Loaded a picture of my project using MFC. Then, a desired part will be drawn with the mouse. It will part the new area. Could you give me an example application.
Mail address : cemil.aksoyy@gmail.com
Example
http://s18.postimage.org/n0yyfmm2t/image.jpg
http://s12.postimage.org/fp0e6jjhl/image.jpg
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Have a look at some of these articles[^] which will help you.
One of these days I'm going to think of a really clever signature.
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here in this constructor :
CommissionEmployee(const string &, const string &,const string &, double=0.0);
why we are using reference & ? whats is the purpose of this ?
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References are used to not have to do copy of the object passed to the constructor, in this case, strings.
If you did not used references, the string would have been copied at least 1 time too many.
Nihil obstat
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References are basically pointers so this of this as an 'address', or a 'reference' to an object.
==============================
Nothing to say.
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The purpose of & in constructor methods is the same it have in any other method: pass arguments by reference (instead of by value).
The usual reason is performance (avoid creating temporaries).
Veni, vidi, vici.
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which is called pass by reference. we can pass arguments in two type
1. pass by value
2. pass by reference
if we use pass by reference same location is passed to functions. no copying is occured. so any changes made is also reflect in original variable. so use const for to provide unexpected changing.
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A constructor is a class member function in C++ and C# that has the same name as the class itself.
The main purpose of the constructor is to initialize all member variables when an object of a said class is created. (Resources acquired such as memory or open files are typically released in the class destructor).
Constructor are automatically invoked when the object is created. Constructor doesn't have any return type, including return voids.
April
Comm100 - Leading Live Chat Software Provider
modified 27-May-14 8:39am.
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i got this error message in my program :
1>Reservation.obj : error LNK2019: unresolved external symbol "public: class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __thiscall Reservation::ID_sn(void)" (?ID_sn@Reservation@@QAE?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@XZ) referenced in function "public: class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __thiscall Reservation::getReservationNumber(void)" (?getReservationNumber@Reservation@@QAE?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@XZ)
and this is the program it contain 2 header files and their cpp file plus the main file
Passenger . h
<pre>#ifndef PASSENGER_H //to avoid redefinition errors
#define PASSENGER_H
#include <iostream>
#include<string>
using namespace std;
class Passenger {
public:
Passenger();
Passenger(string,string,long);
void setPassengerName(string);
void setPassportNumber(string);
void setContactNumber(long);
string getPassengerName();
string getPassportNumber();
long getContactNumber();
void printDetails();
private:
string passengerName;
string passportNumber;
long contactNumber;
};
#endif
Passenger . cpp
<pre>#include <iostream>
#include "Passenger.h"
using namespace std;
Passenger::Passenger(string a="",string b="",long c=0)
{
setPassengerName(a);
setPassportNumber(b);
setContactNumber(c);
}
void Passenger::setPassengerName(string Pname)
{
passengerName=Pname;
}
void Passenger::setPassportNumber(string Pnum)
{
passportNumber=Pnum;
}
void Passenger::setContactNumber(long Cnum)
{
contactNumber=Cnum;
}
string Passenger::getPassengerName()
{
return passengerName;
}
string Passenger::getPassportNumber()
{
return passportNumber;
}
long Passenger::getContactNumber()
{
return contactNumber;
}
void Passenger::printDetails()
{
cout<<"passenger name: "<<getPassengerName()<<"\npassenger Passport Number: "<<getPassportNumber()<<
"\npassenger contact number: "<<getContactNumber()<<"\n\n";
}
Reservation . h
<pre>#ifndef RESERVATION_H_ //to avoid redefinition errors
#define RESERVATION_H_
#include <iostream>
#include <string>
#include "Passenger.h"
using namespace std;
class Reservation{
private:
static int sn;
const string ID;
bool smokerSeat;
Passenger passenger;
public:
Reservation(string psngrName, long psngrPhone, string psngrPassport, bool smoke);
Reservation(Passenger& psngr, bool smoke);
Passenger getPassenger();
bool isSmoker();
string getReservationNumber();
void printDetails();
string ID_sn();
};
#endif /*RESERVATION_H_*/
main .cpp
<pre>#include <iostream>
#include "Passenger.h"
#include "reservation.h"
int main()
{
Passenger passenger1("aar","k9",23596);
Passenger *passengerPtr=&passenger1;
passengerPtr->printDetails();
Reservation reservation("aarr",566,"t77",0);
Reservation *reservationPtr=&reservation;
reservationPtr->printDetails();
system("PAUSE");
}
Im a beginner in programming and that's problem make me really confused
** i think the problem in the Reservation.cpp
Because when i test the other file's it was working but after i added the implementation for the reservation header this problem was appeared
modified 14-Dec-12 7:41am.
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In reservation.h the function ID_sn() is declared. But there is no implementation for this function. In Reservation::getPassenger() you are using this function. Because you are trying to assign a string value to this function, I assume that you wanted to declare a member variable rather a function in reservation.h :
string ID_sn;
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thanks a lot its work
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The error message tells you what the problem is, but it can be hard to understand when you're not used to all the extra template information it spews out.
What it means is that you used a function called "ID_sn" in the getReservationNumber function, both of them are members of the Reservation class, and the linker couldn't find a definition for the ID_sn function.
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thank you i understand it now
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for so long i been trying to learn c++ on my own , but i never got to finish the beginner phase because i always get the feeling im not on the right track ,i always get confused about many stuff like native c++ visual c++ etc...
my goal short term goal is to be able to deal with packets you know decryption\encryption in order to make packet based frame work for online game in other word a bot and of course i wanna go deep into c++ i really enjoy programming but i want to reach goal before i get so bored learning the wrong stuff ,today i decided to ask for help i wanna save time and effort so those of you who knows what should i learn to reach my goal please guide me , tell me what books to read ,what aspects of c++ should i consider as my fundamental information regarding my goal , i dont wanna learn unnecessary information ,dont get me wrong i fully understand that in order to get there i need to learn the very basics but what i want is simply a plan so that i dont get lost or bored in the middle.
thanks in advance
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If you get bored learning the basics then you are never going to get to the advanced parts. You need to understand the basic aspects of the language completely if you wish to succeed as a developer. There is no substitute for study and practice.
One of these days I'm going to think of a really clever signature.
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i dont get bored learning the basics i get bored after ,when i find my self lost , i wanna know what's next , as far as i know basics are the common ground and after you learn them you move to a next phase depending on what you wanna do , for example you wanna be game developer you study certain things , things that are different from someone wanna be windows forms developer ,so my question is what do i have to learn after i finish the basics phase? and thanks for your reply.
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ziuss2 wrote: what do i have to learn after i finish the basics phase? That depends entirely on what you want to do. If you want to develop desktop applications then you can start at Windows Desktop App Development[^]. If you want to move into web programming then try Web Development[^], etc. The information is all out there, but you have to go and study it for yourself.
One of these days I'm going to think of a really clever signature.
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Good. C++ is very powerfull programming language. To study c++ you should start from it's basic knwoledge.
If you are experts in it's basic concepts then you can develop a good c++ knwoledge very fast. i can sujest a very good c++ books that i have been ever read.
1. Effective C++ Third Edition 55 Specific Ways to Improve Your Programs and Designs - by Scott Meyers
This is a very good book from the view of beginers, developers. You can download it pdf by name searching in google.
2. If you want to study MFC with visual c++ then i can sujjest
Programming windows with MFC - Jeff Prosise
This is also a very good book.
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thanks sajeesh.c i will take your book suggestions to consideration and check them out , but still guys you dont get what im trying to do anyways i think im on my own seems that no one sees my realy question which is about what to learn if i wanna make packet base programs for games "bot"
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ziuss2 wrote: what to learn if i wanna make packet base programs for games "bot" Well, the first thing you need to do is explain exactly what you mean by "packet base programs" and "games "bot"".
One of these days I'm going to think of a really clever signature.
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