C / C++ / MFC Discussion Boards

Alan Balkany26-Apr-10 5:08

26-Apr-10 5:08

There will be slight changes in the images even when the target object hasn't changed. The key problem is determining if the changes are enough to conclude the target object has changed.

The first step is to obtain sample data. Capture repeated images of the unchanged object (under different conditions, e.g. day/night). Then capture images of the MINIMUM change in the target object you want to detect.

The next step is to analyze the variation among the images of the unchanged object, and the differences between the images of the changed/unchanged object.

In the easiest case, you'll find a simple threshold that will distinguish between the changed and unchanged cases. It's harder if the noise/illumination differences among the unchanged images exceed the differences between changed/unchanged objects. In this case, you'll need a more complex algorithm.

Two things to look at: 1. Total number of pixels that have changed, and 2. Total number of pixels that have changed by more than a given threshold.

All reports lead to the same thing.

Frank Robertson25-Apr-10 7:17

Frank Robertson

25-Apr-10 7:17

So, Trying to make a 5 card draw poker game using C, and I've come across a hurdle. The following code is randomly choosing cards correctly, but when I try to change them from their deck number to their card, they all come out as the same card. Not sure what is happening, but if you run the program, I put cout statements in to show how the numbers are random.

#include<iostream>
#include<string>
#include<ctime>
#include<cstdlib>
#include <stdlib.h>

using namespace std;

int main()
{
int cardNum1;
int cardNum2;
int cardNum3;
int cardNum4;
int cardNum5;
int cardNum6;
int cardNum7;
int cardNum8;
int cardNum9;
string card1;
string card2;
string card3;
string card4;
string card5;
string card6;
string card7;
string card8;
string card9;
string suit1;
string suit2;
string suit3;
string suit4;
string suit5;
string suit6;
string suit7;
string suit8;
string suit9;

srand(unsigned(time(NULL)));

cardNum1 = (rand()%51 + 1);
cout << cardNum1 << endl;

do
{
cardNum2 = (rand()%51 + 1);
}
while(cardNum2 == cardNum1);

cout << cardNum2 << endl;

do
{
cardNum3 = (rand()%51 + 1);
}
while(cardNum3 == (cardNum1 || cardNum2));

cout << cardNum3 << endl;

do
{
cardNum4 = (rand()%51 + 1);
}
while(cardNum4 == (cardNum1 || cardNum2 || cardNum3));

cout << cardNum4 << endl;

do
{
cardNum5 = (rand()%51 + 1);
}
while(cardNum5 == (cardNum1 || cardNum2 || cardNum3 || cardNum4));

cout << cardNum5 << endl;

do
{
cardNum6 = (rand()%51 +1);
}
while(cardNum6 == (cardNum1 || cardNum2 || cardNum3 || cardNum4 || cardNum5));

cout << cardNum6 << endl;

do
{
cardNum7 = (rand()%51 + 1);
}
while(cardNum7 == (cardNum1 || cardNum2 || cardNum3 || cardNum4 || cardNum5 || cardNum6));

cout << cardNum7 << endl;

do
{
cardNum8 = (rand()%51 + 1);
}
while(cardNum8 == (cardNum1 || cardNum2 || cardNum3 || cardNum4 || cardNum5 || cardNum6 || cardNum7));

cout << cardNum8 << endl;

do
{
cardNum9 = (rand()%51 + 1);
}
while(cardNum9 == (cardNum1 || cardNum2 || cardNum3 || cardNum4 || cardNum5 || cardNum6 || cardNum7 || cardNum8));

cout << cardNum9 << endl;

cout << cardNum1 << ' ' << cardNum2 << ' ' << cardNum3 << ' ' << cardNum4 << ' ' << cardNum5 << endl;
cout << cardNum6 << ' ' << cardNum7 << ' ' << cardNum8 << ' ' << cardNum9 << endl;

if (cardNum1 == 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 11 || 12 || 13)
{
suit1 = "Hearts";
}
else if (cardNum1 == 14 || 15 || 16 || 17 || 18 || 19 || 20 || 21 || 22 || 23 || 24 || 25 || 26)
{
suit1 = "Spades";
}
else if (cardNum1 == 27 || 28 || 29 || 30 || 31 || 32 || 33 || 34 || 35 || 36 || 37 || 38 || 39)
{
suit1 = "Diamonds";
}
else
{
suit1 = "Clubs";
}

if(cardNum1 == 1 || 14 || 27 || 40)
card1 = "Ace";
else if(cardNum1 == 2 || 15 || 28 || 41)
card1 = "Two";
else if(cardNum1 == 3 || 16 || 29 || 42)
card1 = "Three";
else if(cardNum1 == 4 || 17 || 30 || 43)
card1 = "Four";
else if(cardNum1 == 5 || 18 || 31 || 44)
card1 = "Five";
else if(cardNum1 == 6 || 19 || 32 || 45)
card1 = "Six";
else if(cardNum1 == 7 || 20 || 33 || 46)
card1 = "Seven";
else if(cardNum1 == 8 || 21 || 34 || 47)
card1 = "Eight";
else if(cardNum1 == 9 || 22 || 35 || 48)
card1 = "Nine";
else if(cardNum1 == 10 || 23 || 36 || 49)
card1 = "Ten";
else if(cardNum1 == 11 || 24 || 37 || 50)
card1 = "Jack";
else if(cardNum1 == 12 || 25 || 38 || 51)
card1 = "Queen";
else
card1 = "King";

if (cardNum2 == 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 11 || 12 || 13)
suit2 = "Hearts";
else if (cardNum2 == 14 || 15 || 16 || 17 || 18 || 19 || 20 || 21 || 22 || 23 || 24 || 25 || 26)
suit2 = "Spades";
else if (cardNum2 == 27 || 28 || 29 || 30 || 31 || 32 || 33 || 34 || 35 || 36 || 37 || 38 || 39)
suit2 = "Diamonds";
else
suit2 = "Clubs";

if(cardNum2 == 1 || 14 || 27 || 40)
card2 = "Ace";
else if(cardNum2 == 2 || 15 || 28 || 41)
card2 = "Two";
else if(cardNum2 == 3 || 16 || 29 || 42)
card2 = "Three";
else if(cardNum2 == 4 || 17 || 30 || 43)
card2 = "Four";
else if(cardNum2 == 5 || 18 || 31 || 44)
card2 = "Five";
else if(cardNum2 == 6 || 19 || 32 || 45)
card2 = "Six";
else if(cardNum2 == 7 || 20 || 33 || 46)
card2 = "Seven";
else if(cardNum2 == 8 || 21 || 34 || 47)
card2 = "Eight";
else if(cardNum2 == 9 || 22 || 35 || 48)
card2 = "Nine";
else if(cardNum2 == 10 || 23 || 36 || 49)
card2 = "Ten";
else if(cardNum2 == 11 || 24 || 37 || 50)
card2 = "Jack";
else if(cardNum2 == 12 || 25 || 38 || 51)
card2 = "Queen";
else
card2 = "King";

if (cardNum3 == 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 11 || 12 || 13)
suit3 = "Hearts";
else if (cardNum3 == 14 || 15 || 16 || 17 || 18 || 19 || 20 || 21 || 22 || 23 || 24 || 25 || 26)
suit3 = "Spades";
else if (cardNum3 == 27 || 28 || 29 || 30 || 31 || 32 || 33 || 34 || 35 || 36 || 37 || 38 || 39)
suit3 = "Diamonds";
else
suit3 = "Clubs";

if(cardNum3 == 1 || 14 || 27 || 40)
card3 = "Ace";
else if(cardNum3 == 2 || 15 || 28 || 41)
card3 = "Two";
else if(cardNum3 == 3 || 16 || 29 || 42)
card3 = "Three";
else if(cardNum3 == 4 || 17 || 30 || 43)
card3 = "Four";
else if(cardNum3 == 5 || 18 || 31 || 44)
card3 = "Five";
else if(cardNum3 == 6 || 19 || 32 || 45)
card3 = "Six";
else if(cardNum3 == 7 || 20 || 33 || 46)
card3 = "Seven";
else if(cardNum3 == 8 || 21 || 34 || 47)
card3 = "Eight";
else if(cardNum3 == 9 || 22 || 35 || 48)
card3 = "Nine";
else if(cardNum3 == 10 || 23 || 36 || 49)
card3 = "Ten";
else if(cardNum3 == 11 || 24 || 37 || 50)
card3 = "Jack";
else if(cardNum3 == 12 || 25 || 38 || 51)
card3 = "Queen";
else
card3 = "King";

if (cardNum4 == 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 11 || 12 || 13)
suit4 = "Hearts";
else if (cardNum4 == 14 || 15 || 16 || 17 || 18 || 19 || 20 || 21 || 22 || 23 || 24 || 25 || 26)
suit4 = "Spades";
else if (cardNum4 == 27 || 28 || 29 || 30 || 31 || 32 || 33 || 34 || 35 || 36 || 37 || 38 || 39)
suit4 = "Diamonds";
else
suit4 = "Clubs";

if(cardNum4 == 1 || 14 || 27 || 40)
card4 = "Ace";
else if(cardNum4 == 2 || 15 || 28 || 41)
card4 = "Two";
else if(cardNum4 == 3 || 16 || 29 || 42)
card4 = "Three";
else if(cardNum4 == 4 || 17 || 30 || 43)
card4 = "Four";
else if(cardNum4 == 5 || 18 || 31 || 44)
card4 = "Five";
else if(cardNum4 == 6 || 19 || 32 || 45)
card4 = "Six";
else if(cardNum4 == 7 || 20 || 33 || 46)
card4 = "Seven";
else if(cardNum4 == 8 || 21 || 34 || 47)
card4 = "Eight";
else if(cardNum4 == 9 || 22 || 35 || 48)
card4 = "Nine";
else if(cardNum4 == 10 || 23 || 36 || 49)
card4 = "Ten";
else if(cardNum4 == 11 || 24 || 37 || 50)
card4 = "Jack";
else if(cardNum4 == 12 || 25 || 38 || 51)
card4 = "Queen";
else
card4 = "King";

if (cardNum5 == 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 11 || 12 || 13)
suit5 = "Hearts";
else if (cardNum5 == 14 || 15 || 16 || 17 || 18 || 19 || 20 || 21 || 22 || 23 || 24 || 25 || 26)
suit5 = "Spades";
else if (cardNum5 == 27 || 28 || 29 || 30 || 31 || 32 || 33 || 34 || 35 || 36 || 37 || 38 || 39)
suit5 = "Diamonds";
else
suit5 = "Clubs";

if(cardNum5 == 1 || 14 || 27 || 40)
card5 = "Ace";
else if(cardNum5 == 2 || 15 || 28 || 41)
card5 = "Two";
else if(cardNum5 == 3 || 16 || 29 || 42)
card5 = "Three";
else if(cardNum5 == 4 || 17 || 30 || 43)
card5 = "Four";
else if(cardNum5 == 5 || 18 || 31 || 44)
card5 = "Five";
else if(cardNum5 == 6 || 19 || 32 || 45)
card5 = "Six";
else if(cardNum5 == 7 || 20 || 33 || 46)
card5 = "Seven";
else if(cardNum5 == 8 || 21 || 34 || 47)
card5 = "Eight";
else if(cardNum5 == 9 || 22 || 35 || 48)
card5 = "Nine";
else if(cardNum5 == 10 || 23 || 36 || 49)
card5 = "Ten";
else if(cardNum5 == 11 || 24 || 37 || 50)
card5 = "Jack";
else if(cardNum5 == 12 || 25 || 38 || 51)
card5 = "Queen";
else
card5 = "King";

if (cardNum6 == 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 11 || 12 || 13)
suit6 = "Hearts";
else if (cardNum6 == 14 || 15 || 16 || 17 || 18 || 19 || 20 || 21 || 22 || 23 || 24 || 25 || 26)
suit6 = "Spades";
else if (cardNum6 == 27 || 28 || 29 || 30 || 31 || 32 || 33 || 34 || 35 || 36 || 37 || 38 || 39)
suit6 = "Diamonds";
else
suit6 = "Clubs";

if(cardNum6 == 1 || 14 || 27 || 40)
card6 = "Ace";
else if(cardNum6 == 2 || 15 || 28 || 41)
card6 = "Two";
else if(cardNum6 == 3 || 16 || 29 || 42)
card6 = "Three";
else if(cardNum6 == 4 || 17 || 30 || 43)
card6 = "Four";
else if(cardNum6 == 5 || 18 || 31 || 44)
card6 = "Five";
else if(cardNum6 == 6 || 19 || 32 || 45)
card6 = "Six";
else if(cardNum6 == 7 || 20 || 33 || 46)
card6 = "Seven";
else if(cardNum6 == 8 || 21 || 34 || 47)
card6 = "Eight";
else if(cardNum6 == 9 || 22 || 35 || 48)
card6 = "Nine";
else if(cardNum6 == 10 || 23 || 36 || 49)
card6 = "Ten";
else if(cardNum6 == 11 || 24 || 37 || 50)
card6 = "Jack";
else if(cardNum6 == 12 || 25 || 38 || 51)
card6 = "Queen";
else
card6 = "King";

if (cardNum7 == 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 11 || 12 || 13)
suit7 = "Hearts";
else if (cardNum7 == 14 || 15 || 16 || 17 || 18 || 19 || 20 || 21 || 22 || 23 || 24 || 25 || 26)
suit7 = "Spades";
else if (cardNum7 == 27 || 28 || 29 || 30 || 31 || 32 || 33 || 34 || 35 || 36 || 37 || 38 || 39)
suit7 = "Diamonds";
else
suit7 = "Clubs";

if(cardNum7 == 1 || 14 || 27 || 40)
card7 = "Ace";
else if(cardNum7 == 2 || 15 || 28 || 41)
card7 = "Two";
else if(cardNum7 == 3 || 16 || 29 || 42)
card7 = "Three";
else if(cardNum7 == 4 || 17 || 30 || 43)
card7 = "Four";
else if(cardNum7 == 5 || 18 || 31 || 44)
card7 = "Five";
else if(cardNum7 == 6 || 19 || 32 || 45)
card7 = "Six";
else if(cardNum7 == 7 || 20 || 33 || 46)
card7 = "Seven";
else if(cardNum7 == 8 || 21 || 34 || 47)
card7 = "Eight";
else if(cardNum7 == 9 || 22 || 35 || 48)
card7 = "Nine";
else if(cardNum7 == 10 || 23 || 36 || 49)
card7 = "Ten";
else if(cardNum7 == 11 || 24 || 37 || 50)
card7 = "Jack";
else if(cardNum7 == 12 || 25 || 38 || 51)
card7 = "Queen";
else
card7 = "King";

if (cardNum8 == 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 11 || 12 || 13)
suit8 = "Hearts";
else if (cardNum8 == 14 || 15 || 16 || 17 || 18 || 19 || 20 || 21 || 22 || 23 || 24 || 25 || 26)
suit8 = "Spades";
else if (cardNum8 == 27 || 28 || 29 || 30 || 31 || 32 || 33 || 34 || 35 || 36 || 37 || 38 || 39)
suit8 = "Diamonds";
else
suit8 = "Clubs";

if(cardNum8 == 1 || 14 || 27 || 40)
card8 = "Ace";
else if(cardNum8 == 2 || 15 || 28 || 41)
card8 = "Two";
else if(cardNum8 == 3 || 16 || 29 || 42)
card8 = "Three";
else if(cardNum8 == 4 || 17 || 30 || 43)
card8 = "Four";
else if(cardNum8 == 5 || 18 || 31 || 44)
card8 = "Five";
else if(cardNum8 == 6 || 19 || 32 || 45)
card8 = "Six";
else if(cardNum8 == 7 || 20 || 33 || 46)
card8 = "Seven";
else if(cardNum8 == 8 || 21 || 34 || 47)
card8 = "Eight";
else if(cardNum8 == 9 || 22 || 35 || 48)
card8 = "Nine";
else if(cardNum8 == 10 || 23 || 36 || 49)
card8 = "Ten";
else if(cardNum8 == 11 || 24 || 37 || 50)
card8 = "Jack";
else if(cardNum8 == 12 || 25 || 38 || 51)
card8 = "Queen";
else
card8 = "King";

if (cardNum9 == 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 11 || 12 || 13)
suit9 = "Hearts";
else if (cardNum9 == 14 || 15 || 16 || 17 || 18 || 19 || 20 || 21 || 22 || 23 || 24 || 25 || 26)
suit9 = "Spades";
else if (cardNum9 == 27 || 28 || 29 || 30 || 31 || 32 || 33 || 34 || 35 || 36 || 37 || 38 || 39)
suit9 = "Diamonds";
else
suit9 = "Clubs";

if(cardNum9 == 1 || 14 || 27 || 40)
card9 = "Ace";
else if(cardNum9 == 2 || 15 || 28 || 41)
card9 = "Two";
else if(cardNum9 == 3 || 16 || 29 || 42)
card9 = "Three";
else if(cardNum9 == 4 || 17 || 30 || 43)
card9 = "Four";
else if(cardNum9 == 5 || 18 || 31 || 44)
card9 = "Five";
else if(cardNum9 == 6 || 19 || 32 || 45)
card9 = "Six";
else if(cardNum9 == 7 || 20 || 33 || 46)
card9 = "Seven";
else if(cardNum9 == 8 || 21 || 34 || 47)
card9 = "Eight";
else if(cardNum9 == 9 || 22 || 35 || 48)
card9 = "Nine";
else if(cardNum9 == 10 || 23 || 36 || 49)
card9 = "Ten";
else if(cardNum9 == 11 || 24 || 37 || 50)
card9 = "Jack";
else if(cardNum9 == 12 || 25 || 38 || 51)
card9 = "Queen";
else
card9 = "King";

cout << "1. " << card1 << " of " << suit1 << endl;
cout << "2. " << card2 << " of " << suit2 << endl;
cout << "3. " << card3 << " of " << suit3 << endl;
cout << "4. " << card4 << " of " << suit4 << endl;
cout << "5. " << card5 << " of " << suit5 << endl;
cout << "6. " << card6 << " of " << suit6 << endl;
cout << "7. " << card7 << " of " << suit7 << endl;
cout << "8. " << card8 << " of " << suit8 << endl;
cout << "9. " << card9 << " of " << suit9 << endl;

cin.get();
cin.get();

return 0;
}

Re: All reports lead to the same thing.

Frank Robertson25-Apr-10 7:19

Frank Robertson

25-Apr-10 7:19

Sorry for it being so long. First programming class, so I can only use what I know.

The includes didn't copy correctly, so here they are.

#include<iostream>
#include<string>
#include<ctime>
#include<cstdlib>
#include <stdlib.h>

Re: All reports lead to the same thing.

Luc Pattyn25-Apr-10 7:30

Luc Pattyn

25-Apr-10 7:30

Hi,

probably lots of problems in your code; I didn't look at it in any detail as there is a lot of it and it is badly formatted. Next time use PRE tags so it gets to preserve its original formatting and indentation, and gets shown in a non-proportional font, with syntax coloring.

if(cardNum9 == 8 || 21 || 34 || 47) is not what you want; you mean
if(cardNum9 == 8 || cardNum9 == 21 || cardNum9 == 34 || cardNum9 == 47)

which you probably could write as just if((cardNum9 % 13) == 8)

Whay you wrote is ORing all the numbers, treating them as booleans, hence the result is always 1 (unless all your numbers were 0).

Strong suggestion: if you are familiar with arrays, start using them right now. You can do what you have with one fifth of the code you have now, and less code means less trouble and fewer bugs. You will waste a lot of time by not using arrays!

and why is it %51 and not %52???????????????

Smile | :)

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modified on Sunday, April 25, 2010 1:44 PM

Re: All reports lead to the same thing.

Frank Robertson25-Apr-10 8:14

Frank Robertson

25-Apr-10 8:14

Thanks for the quick reply, Luc.

I'll plug the new way of doing the numbers into my code in a little while, hopefully they will work, but my wrists are starting to cramp from all the playing in the code I've been doing.

The class I am in doesn't start array's until next week, so that's why I haven't used any yet, but I do plan to use them. I just wanted to get a jump-start on my final project and see what I could do with what I know.

And I have it as %51+1 instead of %52, because doesn't %52 give you all the numbers from 0-52? I don't need 0 so by adding the +1 to %51, I make it 1-52.

Re: All reports lead to the same thing.

Luc Pattyn25-Apr-10 8:17

Luc Pattyn

25-Apr-10 8:17

as %N returns the remainder after division by N, what do you think the largest value of %N could be?

without arrays, make sure to consider using a lot of modulo operators! I already gave you an example.

Smile | :)

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Prolific encyclopedia fixture proof-reader browser patron addict?
We all depend on the beast below.

Re: All reports lead to the same thing.

C^hris L^osinger25-Apr-10 8:25

C^hris L^osinger

25-Apr-10 8:25

just a note.

the % operator has a lower precedence than the + operator. so you code is really doing this: rand() % 52 . that is, the addition (51 + 1) happens before the %.

this might be closer to what you want: (rand() % 51) + 1

don't know if it will solve your problem, tho.

image processing toolkits | batch image processing

Re: All reports lead to the same thing.

CPallini25-Apr-10 21:05

CPallini

25-Apr-10 21:05

Have also a look at my tip: "Random extraction of 5 cards from a deck" to avoid unnecessary verification steps.
Smile | :)

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Template: how to detect type

428825-Apr-10 2:04

4288

25-Apr-10 2:04

I wrote a template class which can accept various data types (I had different kind of data to handle)

All the data type I used with this template-class, are structures with common parameters.

Now I need to write a common code to all classes (I was thinking of a function with his own class) to use these "common" parameters.

The solutions I thought are:

1) Passing a void* pointer to the function and select the appropriate code for the datatype:

void Function( void *pointer_to_custom_data, ENUM_DATA_TYPE)
{
if(ENUM_DATA_TYPE == DATA_TYPE1)
// specific code for type1..
else if (ENUM_DATA_TYPE == DATA_TYPE2)
// specific code for type2..
...

}

2) Overloading in some way this function (don't know how though) so it recognize the type used and uses the specific code

Any better idea or suggestion on how to implement these?

---

Re: Template: how to detect type

Code-o-mat25-Apr-10 3:03

Code-o-mat

25-Apr-10 3:03

I'm not sure i completely understand your problem, but the first thought that comes to my mind is: why don't you have a common base class for your structures that contains the common "parameters" you are talking about, then you can make a method that takes a pointer/reference to this base class and does with the parameters what it should. Or do you mean that you have to do different things depending on the type of struct? Then use a virtual function declared in the base class and implement it according to your needs in all the subclasses. Am i misunderstanding you?

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Sometimes you just have to hate coding to do it well. <

Re: Template: how to detect type

Richard MacCutchan25-Apr-10 3:07

Richard MacCutchan

25-Apr-10 3:07

You should, if possible, make the function part of the template class, thus ensuring type safety throughout. See the MSDN documentation on Templates[^] for more information.

It's time for a new signature.

Re: Template: how to detect type

Saurabh.Garg25-Apr-10 3:42

Saurabh.Garg

25-Apr-10 3:42

This looks likes bad design to me. Template class should not be explicitly aware of the types it can be used with. It can define the requirements in the types but that is all.

In your case it looks like better option is to use inheritance instead of template class. Unless of course you have presented a simplified picture.

I will suggest you inherit the structures from a common base class. This base class will contain common parameters and a pure virtual function. Inherited structures will override this function providing the type specific functionality.

-Saurabh

Re: Template: how to detect type

«_Superman_»25-Apr-10 6:55

«_Superman_»

25-Apr-10 6:55

If you want type specific code, you do not write a template class.
In some cases, for template classes you need a special implementation for a certain type.
In these cases you can do template specialization.

Assume you have a template class called Math -

template<typename T>
class Math
{
};

You may need special implementation for some data type like complex.
In this case you can specialize the template class for the complex data type.

template<>
class Math<complex>
{
};

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++)

Re: Template: how to detect type

Stuart Dootson25-Apr-10 13:04

Stuart Dootson

25-Apr-10 13:04

Function specialisation. Specialization if you're American.

Use the standard template case for the common code, specialisations for code specific to types. Like this:

#include <iostream>

template<class _Type>
void Fn(_Type const&)
{
   std::cout << "Generic..." << std::endl;
}

template<>
void Fn<int>(int const&)
{
   std::cout << "int specialisation" << std::endl;
}

int main()
{
   Fn('a');
   Fn(10);
}

The output you get is:

Generic...
int specialisation

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

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Re: Template: how to detect type

428826-Apr-10 2:53

4288

26-Apr-10 2:53

I'm not dead, I was just looking at your suggestions and see whether they're appliable to my project.

Thank you guys but I realized some things:

1) I'm an idiot
2) More than half of my project has to be rewritten. I can't specializate template class because datatype are too much.
3) Project is slow as hell, I screwed it up with template of templates and at runtime it has to calculate every damn address it uses

I think I'm going to change a lot of things... thank you for your help!

---

Re: Template: how to detect type

Moak26-Apr-10 4:53

Moak

26-Apr-10 4:53

Hi 4288! My spontaneous reaction was, why does he use templates and not polymorphism... but I wanted to see what others say.

Perhaps it can help you in your design to have an abstract base class CObject and then derive classes from that base class with further specialisation. You would then only need one template for the base class (or if it is about storing data something like std::vector<CObject*>). In C++ virtual methods will be called virtual even via a base class pointer, quite handy. Hard to give better tips without seeing your architecture or requirements. Looks like Saurabh gave the same advice.

Hope it helps... and happy refactoring! Smile | :)

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ForNow24-Apr-10 21:52

ForNow

24-Apr-10 21:52

Does setting a carriage return '/r' in callback
streamin Richeditctrl cause the text to go
to a new line

Re: ESTREAMIN carriage return

Stuart Dootson25-Apr-10 1:31

Stuart Dootson

25-Apr-10 1:31

I've no idea - but two suggestions…

1) Try it and see (try a '\n').
2) Enter some multi-line text into a rich-edit control and see what comes out when you use the EM_STREAMOUT message

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Re: ESTREAMIN carriage return

ForNow25-Apr-10 2:17

ForNow

25-Apr-10 2:17

I have a ES_AUTOSCROLL style maybe I
should take that out and try to size the editctrl
to some optimum size

how to get the filepath which is selected?

kobe893624-Apr-10 20:57

kobe8936

24-Apr-10 20:57

Maybe something about the mouse hook...
When I click some file's icon ,then how to return its path?
Thanks!

Re: how to get the filepath which is selected?

Code-o-mat24-Apr-10 22:16

Code-o-mat

24-Apr-10 22:16

I believe you should provide more details about what you want to do, till now it isn't obvious what you mean...

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Sometimes you just have to hate coding to do it well. <

Re: how to get the filepath which is selected?

kobe893624-Apr-10 22:41

kobe8936

24-Apr-10 22:41

I am doing a work like a monitor.
I mean when I click some file'icon on the desktop , for example ,system will return a messagebox says "this file's path is ...".
How can the system know what I have chosen?
I need system return the file's path.

Re: how to get the filepath which is selected?

Code-o-mat24-Apr-10 23:05

Code-o-mat

24-Apr-10 23:05

I personally don't know any standard way to do what you want (which of course does not mean there isn't any).
You could try hooking into explorer.exe, subclass the list control that hosts the icons on the desktop, or the window that receives notifications from the list view, or installing a (system-wide?) message hook, to find out when and to what the selection changes. Then you could use SHGetDesktopFolder[^] and use IShellFolder::EnumObjects[^] to find the path for the selected item, if it has any. How you would find out which icon belongs to which shell objects is beyond me at this point, you could try finding that object by the name the icon shows but this is probably a bad idea (for example if i have a "myFile.pdf" and a "myFile.txt" sitting on my desktop, i think both will have the name "myFile", the extension is hidden, or at least can be). If you are lucky then the items' itemdata contains something that can be used to identify them, for example a pointer to a IDList or somesuch, then you could even skip the "look up" part thorough the enumeration. This whole thing is just an idea and not a simple one at that...

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Sometimes you just have to hate coding to do it well. <

Re: how to get the filepath which is selected?

kobe893624-Apr-10 23:47

kobe8936

24-Apr-10 23:47

Oh, I am still a freshman and what you said is really hard for me..
Haha, still, thank you very much!
I will try.. Laugh | :laugh:

Re: how to get the filepath which is selected?

Code-o-mat25-Apr-10 0:07

Code-o-mat

25-Apr-10 0:07

If you are a freshman i recommend starting with something simpler, anyways, good luck. Thumbs Up | :thumbsup:

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Sometimes you just have to hate coding to do it well. <

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