Define triangle class - C / C++ / MFC Discussion Boards

Re: template question

Joaquín M López Muñoz9-Oct-03 21:08

Joaquín M López Muñoz

9-Oct-03 21:08

Then don't Smile | :)

You cannot write code outside a function just like that. It is like if you dropped a printf("hello") outside a function, you get this is not legal, right? Put your code inside some function and things will probably work (or at least your error chasing will move one step further.)

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: template question

Steve Messer9-Oct-03 21:11

Steve Messer

9-Oct-03 21:11

Your my hero.

Thanks, you are always so helpful.

Steve

Re: template question

Joaquín M López Muñoz9-Oct-03 21:23

Joaquín M López Muñoz

9-Oct-03 21:23

You can have the plugin loaded without any "inside" code if you define the ctor as

CPlugin(const char* szDLLName, const char* szFunction){/* code for Loading*/}

and provide some GetPlugin accesor for later use. IMHO this is probably better than the Load scheme, since the only purpose of CPlugin is to make the loading anyway. Following this approach, you might want to move the unloading code to the dtor of the class and supress the explicit loading functions altogether. This fits nicely with a C++ idiom called RAII (Resource Acquisition is Initialization), which you can google for for further info.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: template question

Steve Messer9-Oct-03 21:30

Steve Messer

9-Oct-03 21:30

Thanks for the sugguestion. I will look into it.

Steve

Re: template question

Steve Messer9-Oct-03 21:08

Steve Messer

9-Oct-03 21:08

Ok, I just put:

PLUGIN.Load("HTPCPlugin.dll", "GetPlugin");

inside of a function and it compiled beautifully.

I am new to templates so what is going on here?

Steve

Strange things with parameters.

esepich9-Oct-03 19:10

esepich

9-Oct-03 19:10

There is surely something I do not understand here. I would very much appreciate if someone could explain to me how I screwed this up.

Thank you.

--------------------Configuration: TCPIPwatch - Win32 Debug--------------------
Compiling...
TCPIPwatchDlg.cpp
C:\DOCUMENTS AND SETTINGS\ADMIN\DESKTOP\SSPROJECT\TCPIPwatch\TCPIPwatchDlg.cpp(235) : error C2664: 'bind' : cannot convert parameter 2 from 'struct CTCPIPwatchDlg::TCPIPWConnectSock::SOCKADDR_IN *' to 'const struct sockaddr *'
Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
Error executing cl.exe.

TCPIPwatch.exe - 1 error(s), 0 warning(s)

void CTCPIPwatchDlg::TCPIPWConnectSock(SOCKADDR_IN *dest, SOCKET &theTrgSock)
{
dest->sin_family = AF_INET;
dest->sin_port = 80;

if(dest->sin_port == INVALID_SOCKET)
AfxMessageBox("Port is invalid.",MB_OK);

theTrgSock = socket(AF_INET, SOCK_RAW, IPPROTO_IP);

const char RCVTIMEO[50] = "5000";
setsockopt(theTrgSock, SOL_SOCKET, SO_RCVTIMEO, (RCVTIMEO), 4);
bind(theTrgSock, (struct SOCKADDR_IN*) dest, sizeof(dest));
}

Re: Strange things with parameters.

Anand Paranjpe9-Oct-03 19:52

Anand Paranjpe

9-Oct-03 19:52

Hi,

typecast with (const ::SOCKADDR*) to 2nd parameter for function bind().

Cheers Smile | :)

The chosen One Smile | :)

Define triangle class

Anonymous9-Oct-03 18:40

Anonymous

9-Oct-03 18:40

Well, I am comming along more and more with this program, but I could still obviously use some help. I am going to put the specifications in full out here.

Define a class for triagnles. A triangle is defined by three sides. Class should have following capabilities:

A constructor that will allow definining a triangle. (float side1, float side2, float side3). The constructor is to call Order to place the sides in order from smallest to largest.

A constructo with no arguments: initialize the three sides to zero.

Public member functions needed.

void SetTriangle(float side1, float side2, float side3);
bool IsEquilateral();
bool IsIsosceles();
bool IsScalene();
bool IsRight();
bool IsAcute();
bool IsObtuse();
friend Triangle Copy(Triangle triangle1);
friend bool operator ==(const Triangle& triangle1, const Triangle& triangle2);
friend ostream& operator <<(ostream& outs, Triangle& the_triangle);

Private member functions needed.

void Order;
void Swap;

I need to write a program that will define triangle1, triangle2, triangle3, triangle4

am to define a class for triangles, and once I have defined it I need to do tese procedurse:

The constructor (with sides) is to call order to order the sides from smallest to largest.
and
The SetTriangle function is to call order to order the sides from smallest to largest

and then display the sides and the type it is... scalene and right, isosceles and acute, ....

I think I may need to give more detail. Triangle1 will not have any values defined. Triangle2 has sides 6.0, 6.0, 6.0. Triangle3: 5.0, 4.0, 3.0. Triangle4: 6.0, 4.0, 4.0

And then for Triangles 2, 4, and 4... I

1) Use friend operator function << to display the three sides of each

2) Test to see if the triangle is Equilateral, Isosceles, or Scalene. When one of the functions returns true, display message. Message should not be displayed within function.

3) Test to see if Right, Acute, Obtuse

For the copy test

1) Use the friend copy function to copy triangle 4 to triangle 1

2) Use friend operator function << to display the three sides of triangle 4 and triangle 1.

3)Use friend operator function == to see if triangle 1 is equal to triangle 4. If the two are, display " are equal", otherwise " are not equal.

For another == test, do the following

1)Use friend operator function << to display three sides of triangle2 and triangle3.

2)Use friend operator function ++ to see if triangle2 is equal to triangle3 and display appropriate message

For the SetTriangle test, do the following:

1)set Triangle3's sides to (5, 4, 3 (in that order))

2)use friend operator function << to disply the three sides of triangle3.

There are all the specifications and what not. It has been like a week... and I have only gotten as far as this Could I please get some help all around on this one. I would so much appreciate it. Please, could I get some help. I have done this much on my own, and now I have just gotten stuck and don't really have a clue as what to do.

My code is

#include <iostream.h><br />
#include <stdlib.h><br />
<br />
class Triangle<br />
{<br />
public:<br />
	friend Triangle Copy(Triangle triangle1);<br />
	friend bool operator ==(const Triangle& triangle1, const Triangle& triangle2);<br />
	friend ostream& operator <<(ostream& outs, Triangle& the_triangle);<br />
<br />
	Triangle(float side1, float side2, float side3);<br />
	Triangle();<br />
<br />
	void SetTriangle(float side1, float side2, float side3);<br />
<br />
	bool IsEquilateral();<br />
	bool IsIsosceles();<br />
	bool IsObtuse();<br />
<br />
	float get_side1();<br />
	float get_side2();<br />
	float get_side3();<br />
<br />
private:<br />
    void order(float side_1, float side_2, float side_3);<br />
	void swap(float side_1, float side_2);<br />
<br />
	float side_1, side_2, side_3;<br />
};<br />
<br />
void main()<br />
{<br />
	Triangle triangle1, triangle2(5.0, 4.0, 3.0), triangle3(6.0, 4.0, 4.0);<br />
	cout << "Display triangle 1:\n";<br />
	cout << "Side 1 = " << triangle1.get_side1() << endl;<br />
	cout << "Side 2 = " << triangle1.get_side2() << endl;<br />
	cout << "Side 3 = " << triangle1.get_side3() << endl;<br />
<br />
	cout << "Display triangle 2:\n";<br />
	cout << "Side 1 = " << triangle2.get_side1() << endl;<br />
	cout << "Side 2 = " << triangle2.get_side2() << endl;<br />
	cout << "Side 3 = " << triangle2.get_side3() << endl;<br />
<br />
	cout << "Display triangle 3:\n";<br />
	cout << "Side 1 = " << triangle3.get_side1() << endl;<br />
	cout << "Side 2 = " << triangle3.get_side2() << endl;<br />
	cout << "Side 3 = " << triangle3.get_side3() << endl;<br />
<br />
}<br />
<br />
<br />
Triangle Copy(Triangle triangle1)<br />
{<br />
	Triangle copy;<br />
<br />
	copy.order = triangle1;<br />
	return copy;<br />
}<br />
Triangle::Triangle(float side1, float side2, float side3)<br />
{<br />
	side_1 = side1;<br />
	side_2 = side2;<br />
	side_3 = side3;<br />
}    <br />
<br />
void swap(float side_1, float side_2)<br />
{<br />
	float temp;<br />
	temp = side_1;<br />
	side_1 = side_2;<br />
	side_2 = temp;<br />
}<br />
<br />
void order(float side_1, float side_2, float side_3)<br />
{<br />
	if (side_1 > side_2)<br />
		swap (side_1, side_2);<br />
	if (side_1 > side_3)<br />
		swap (side_1, side_3);<br />
	if (side_2 > side_3)<br />
		swap (side_2, side_3);<br />
}<br />
<br />
<br />
<br />
Triangle::Triangle() : side_1(0), side_2(0), side_3(0)<br />
{<br />
	//empty<br />
}<br />
float Triangle::get_side1()<br />
{<br />
	return side_1;<br />
}<br />
float Triangle::get_side2()<br />
{<br />
	return side_2;<br />
}<br />
float Triangle::get_side3()<br />
{<br />
	return side_3;<br />
}

Re: Define triangle class

W. Hammer -sledge-11-Oct-03 9:29

W. Hammer -sledge-

11-Oct-03 9:29

OK, let me see, if i understood you correctly.

You want to use an overloaded operator << . But what you have done, is only using the normal output of an float.

The overloading would look like this:

ostream& operator<< (ostream& ostr, CTriangle& triangle)
{
   ostr << "Side1 = " << triangle.side1 << endl
        << "Side2 = " << triangle.side2 << endl
        << "Side3 = " << triangle.side3 << endl;
   return ostr;
}

The overloaded operator== looks like this:

bool operator ==(const CTriangle& tri1, const CTriangle& tri2)
{
   if (tri1.side1 == tri2.side1
       && tri1.side2 == tri2.side2 
       && tri1.side3 == tri2.side3)
      return true;
   else
      return false;
}

My personal advice:
You should divide your program into three files.
-----------------------
First file -
a file containing the declaration of the triangle class. Name this file triangle.h
!! Remember that triangle is a class, so name the class CTriangle. !!
-----------------------
Second file -
Name this file triangle.cpp

include your triangle.h by using
#include "triangle.h"

Now put all the definitions of your CTriangle class in here (for instance yout get-functions etc. and the overloaded operators). Don't forget neccessary inclusions like iostream.h

-----------------------
Third file -
name this file main.cpp

include your triangle.h by using

#include "triangle.h"
#include <iostream.h>

void main()
{
  CTriangle triangle1, triangle2(5.0, 4.0, 3.0), triangle3(6.0, 4.0, 4.0);
  cout << "Display triangle 1:\n";
  cout << triangle1 ;

  cout << "Display triangle 2:\n";
  cout << triangle2 ;

  cout << "Display triangle 3:\n";
  cout << triangle3;

  if (triangle2 == triangle3)
    cout << "identical" << endl;
  else
    cout << "not identical" << endl;
<

}

I havent compiled it, but this should work. Test it by changing the values of the triangle2 and triangle3.

Hope this helps
sledge

Hello ÕâÊÇÊ²Ã´Ñ½£¿

hy_huangh9-Oct-03 18:36

hy_huangh

9-Oct-03 18:36

ÓÃÖÐÎÄ¶àºÃ£¬Ó¢ÎÄ¿´²»¶®£¡;P

Re: Hello ÕâÊÇÊ²Ã´Ñ½£¿

David Stone9-Oct-03 18:56

David Stone

9-Oct-03 18:56

Yeah....that's probably not going to compile.

When I can talk about 64 bit processors and attract girls with my computer not my car, I'll come out of the closet. Until that time...I'm like "What's the ENTER key?"
-Hockey on being a geek

Floating point calculation

act_x9-Oct-03 18:20

act_x

9-Oct-03 18:20

heres my problem

float r=10.3;
int x=10;
int z=ceil(r*x) gives me 104 . I need 103

I need output to be converted as
if product = 103.1 o/p = 104
if product = 103.0 o/p=104
if product = 103.5 o/p = 104
Basically i dont want it to take the upper no if the product can be equivalently represented by an integer
what i mean is 103.0 is actually 103
but 103.1 isnt 103

Re: Floating point calculation

Anand Paranjpe9-Oct-03 20:05

Anand Paranjpe

9-Oct-03 20:05

Hi
double r=10.3;
int x=10;
int z= ::ceil(r*x);
will give 103

Chill Smile | :)

The chosen One Smile | :)

Re: Floating point calculation

Anthony_Yio10-Oct-03 1:09

Anthony_Yio

10-Oct-03 1:09

<code>float x = 3.01; x = ((int)x< ceil (x) )?(int)x:(int)x+1; </code>
a rough try Smile | :)

Sonork 100.41263:Anthony_Yio

Re: Floating point calculation

JWood10-Oct-03 9:59

JWood

10-Oct-03 9:59

It's most likely round off error.
internally it figures that it is 103.0000000000001 and so it rounds up to 104. Look into the IEEE format used to store floats to figure out why.

J.
----------------------------

XML parsing with DOM??

xxhimanshu9-Oct-03 17:45

xxhimanshu

9-Oct-03 17:45

hi all,

i have an XML file..where i have some data as
<keywords>
<keyword>.net
<keyword>0% credit card
<keyword>0% interest credit card
<keyword>1 800 contacts
<keyword>1 800 flower
<keyword>1-800 flower
<keyword>1-800-flowers

I want to perform a search over this XML file as if i have "1-800-flowers". I dont want it to go thru each element and then reach there..it is a slow process as it goes in loop for each keyword tag..is there any way where i can perform a fast search for the data i have..so that it is fast..i am using VC++ with MSXML..Please help me out..
Thanks a lot in advance..
regards,

Himanshu

Re: XML parsing with DOM??

act_x9-Oct-03 18:28

act_x

9-Oct-03 18:28

net
0% credit card
0% interest credit card
1 800 contacts
1 800 flower
1-800 flower
1-800-flowers

all this is the data embedded between tags that have the same name
like
<MYTAG>1 800 blah 1 </MYTAG>
<MYTAG>1 800 blah 2 </MYTAG>
<MYTAG>1 800 blah 3 </MYTAG>
<MYTAG>1 800 blah 4</MYTAG>

Then I am afraid u ll have to go thru each node and find out . if the tags are unique u can do a "getElementsByTagName" defined by DOM .

Engineering is the effort !

Re: XML parsing with DOM??

Anand Paranjpe9-Oct-03 20:09

Anand Paranjpe

9-Oct-03 20:09

hi,
post proper XML u r using to get soln or or look into XPath query language on MSDN.

The chosen One Smile | :)

Re: XML parsing with DOM??

Ravi Bhavnani10-Oct-03 3:25

Ravi Bhavnani

10-Oct-03 3:25

You could use XPath (Xalan). Not sure how compatible it is with MSXML. I use Xerces to parse XML.

/ravi

Let's put "civil" back in "civilization"
Home | Articles | Freeware | Music
ravib@ravib.com

what does this mean?

FlyingDancer9-Oct-03 17:34

FlyingDancer

9-Oct-03 17:34

Here is a sentence:

using namespace std

Could you tell me what is its meaning?

Re: what does this mean?

Anand Paranjpe9-Oct-03 20:15

Anand Paranjpe

9-Oct-03 20:15

Hi,

"using namespace std;" means in ur program u r using namespace called as "std" provided by microsoft. all STL functionality u will get under this namespace.
Why we use namespaces? Smile | :)

To avoid name collision.
Compiler tries to interpret objects or function calls user namespace if specified else searches in global namespace by default.

More info is given in MSDN. Smile | :)

The chosen One Smile | :)

Re: what does this mean?

FlyingDancer9-Oct-03 21:26

FlyingDancer

9-Oct-03 21:26

Oh,I see
Thank you
In fact, I haven't found the result from MSDN as to using namespace std
Smile | :)

Thank you again

Re: what does this mean?

David Crow10-Oct-03 6:02

David Crow

10-Oct-03 6:02

shalala wrote:
In fact, I haven't found the result from MSDN as to using namespace std

Try here:

http://msdn.microsoft.com/library/en-us/vclang98/html/_pluslang_using_declaration.asp?frame=true

http://msdn.microsoft.com/library/en-us/vclang98/html/_pluslang_using_directive.asp?frame=true

Five birds are sitting on a fence.
Three of them decide to fly off.
How many are left?

Re: what does this mean?

FlyingDancer12-Oct-03 3:31

FlyingDancer

12-Oct-03 3:31

Thanks you very much!
Rose | [Rose]

Mutex Objects, Semaphore Objects and Critical Section Objects

FlyingDancer9-Oct-03 17:23

FlyingDancer

9-Oct-03 17:23

These three ways can work well for multi-Threaded design.

They must be some differnt in some aspects although They look very alike.
Could you tell me the differnt between them, please!

Thanks in advance!

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.