It depends on the technique you want to use. Look at blas.org or lapack for ready made libraries. Just in case you dont know, matrix inversion is not done in most actual cases. The system is usually solved using one of the known Linear Algebra techniques like QR Factorization, LU decomposition and so on.
Saturday, May 9, 2009
I need a research papere on business management for reference b/c I am MBA student . by Asfaw Yilma?
I need any kinds of research relating the business management including; enterprise marketing,information management,production and logistic management,human resourse management,financial management,project management,common enterprise management,and the likes with reference to specific area.Also if available the proposals.
I need a research papere on business management for reference b/c I am MBA student . by Asfaw Yilma?
I recommend that you take this to your local research librarian, found at your local school or city library. Those people have the best idea of how to find large bodies of research, such as you're trying to find. They focus better than doing an internet search yourself (or myself, for that matter).
flowers uk
I need a research papere on business management for reference b/c I am MBA student . by Asfaw Yilma?
I recommend that you take this to your local research librarian, found at your local school or city library. Those people have the best idea of how to find large bodies of research, such as you're trying to find. They focus better than doing an internet search yourself (or myself, for that matter).
flowers uk
How 2 buy t papers presented by somebody tat i want 2 c 4 reference?
i am preparing for paper presentation on the topic"mobile computing",so i just want to go through other papers for some references and i dont know how to buy those presentations in hard copy so i require some details......
How 2 buy t papers presented by somebody tat i want 2 c 4 reference?
Go to the library and do a search for that topic in journals. Buying someone elses work is cheating. You can see professional works in journals and they will help you and you can use them as a reference in your own paper.
Reply:hey hey dude do not worry u can just dial 28888888 / 39999999 with your respective city code or u can visit this site
www.justdial.com
How 2 buy t papers presented by somebody tat i want 2 c 4 reference?
Go to the library and do a search for that topic in journals. Buying someone elses work is cheating. You can see professional works in journals and they will help you and you can use them as a reference in your own paper.
Reply:hey hey dude do not worry u can just dial 28888888 / 39999999 with your respective city code or u can visit this site
www.justdial.com
Why does TV show Arrested Development reference "O.C." alot?
I know they live in the O.C., but a number of times, someone on the show says "The O.C." and someone else says "don't say that". Is it some inside joke?
Why does TV show Arrested Development reference "O.C." alot?
They were both shows made by Fox network,they would mention it as a plug for their own network.
Why does TV show Arrested Development reference "O.C." alot?
They were both shows made by Fox network,they would mention it as a plug for their own network.
I need a free download of C++ Complete Reference using Adobe reader pdf file?
Whose C++? Borland, IBM, or others?
Here's the IBM VisualAge C++ Professional for AIX
http://www-1.ibm.com/support/docview.wss...
Here's the IBM VisualAge C++ Professional for AIX
http://www-1.ibm.com/support/docview.wss...
Parse string by reference in C?
I want to know how to parse a string by reference to a function.
For example
void func( char* thefunc);
char * test ="thestr";
func( test )
{
//modify test by reference
}
so how to modify the string test without having to put a return in the function "func"??
Parse string by reference in C?
Like this:
#include %26lt;stdio.h%26gt;
void swapnum(int *i, int *j) {
int temp = i;
i = j;
j = temp;
}
int main(void) {
int a = 10;
int b = 20;
/* Pass by reference */
swapnum(%26amp;a, %26amp;b);
printf("A is %d and B is %d\n", a, b);
return 0;
}
Reply:When you use a string 'by reference' it means you don't pass a copy of the string to the function, instead you pass an address where the string is, and the function accesses it wherever it is.
In this case you passing a pointer to the first character of the string. The function can read the string character by character (test, test+1, test+2, etc.), until it reaches a zero, then it knows that's the end.
Since the function accesses the string where it is, instead of a copy of the string, it doesn't have to return anything. When it's done, the string is changed, but still in the same place (test).
Reply:See http://c-faq.com/aryptr/aryptrequiv.html . C strings are just character arrays. In C, you can --never-- pass arrays by value. They will always be by reference. You don't have to return anything. If you modify the string in your function, it will be modified permanently.
Just a caveat. Even though in your function the C string has pointer semantics, do not originally create the string by directly pointing to a literal. You need to either allocate memory for an array (either by directly creating it on the stack or pointing a dynamically allocated array), and then pass that to the function.
Reply:Here is an example code you want in func.
func( test )
{
//modify test by reference
*(test+0)='a';
*(test+1)='b';
*(test+2)='c';
}
this will change the acutal string.test.
so in the after calling func(test) from main, print the string. You will have the requried change (i.e) it will print abcstr instead of thestr.
You can write any code instead of replacing the first 3 charecters with 'a','b','c'.
--------------------------------------...
hamper
For example
void func( char* thefunc);
char * test ="thestr";
func( test )
{
//modify test by reference
}
so how to modify the string test without having to put a return in the function "func"??
Parse string by reference in C?
Like this:
#include %26lt;stdio.h%26gt;
void swapnum(int *i, int *j) {
int temp = i;
i = j;
j = temp;
}
int main(void) {
int a = 10;
int b = 20;
/* Pass by reference */
swapnum(%26amp;a, %26amp;b);
printf("A is %d and B is %d\n", a, b);
return 0;
}
Reply:When you use a string 'by reference' it means you don't pass a copy of the string to the function, instead you pass an address where the string is, and the function accesses it wherever it is.
In this case you passing a pointer to the first character of the string. The function can read the string character by character (test, test+1, test+2, etc.), until it reaches a zero, then it knows that's the end.
Since the function accesses the string where it is, instead of a copy of the string, it doesn't have to return anything. When it's done, the string is changed, but still in the same place (test).
Reply:See http://c-faq.com/aryptr/aryptrequiv.html . C strings are just character arrays. In C, you can --never-- pass arrays by value. They will always be by reference. You don't have to return anything. If you modify the string in your function, it will be modified permanently.
Just a caveat. Even though in your function the C string has pointer semantics, do not originally create the string by directly pointing to a literal. You need to either allocate memory for an array (either by directly creating it on the stack or pointing a dynamically allocated array), and then pass that to the function.
Reply:Here is an example code you want in func.
func( test )
{
//modify test by reference
*(test+0)='a';
*(test+1)='b';
*(test+2)='c';
}
this will change the acutal string.test.
so in the after calling func(test) from main, print the string. You will have the requried change (i.e) it will print abcstr instead of thestr.
You can write any code instead of replacing the first 3 charecters with 'a','b','c'.
--------------------------------------...
hamper
Learning C++ / Experience with C++ All-in-one Desk Reference for Dummies?
I am learning C++, and I currently own C++ All-in-one desk reference For Dummies. Any tips on books, websites, or anything of the like?
Learning C++ / Experience with C++ All-in-one Desk Reference for Dummies?
My favroite site is www.cplusplus.com
Practice is far more important than reading books. Its important to be trying every bit of code you see until you understand it in and out. Books are good when you need a reference and some theory.
As for software, for an absolute beginer I really recomend Microsoft's Visual C++ because it makes it easy to do lots of trial and error which is really important part of early stages of learning to program. It also has a good detailed reference.
Free version available here: http://msdn.microsoft.com/vstudio/expres...
Keep in mind though there are other compilers and not all are compatable with ANSI Standard C++. g++ is very popular compiler on LINUX. Borland and Devshed are others for windows. But I have yet to see the user friendliness of Visual Studio in any other software for C++.
Learning C++ / Experience with C++ All-in-one Desk Reference for Dummies?
My favroite site is www.cplusplus.com
Practice is far more important than reading books. Its important to be trying every bit of code you see until you understand it in and out. Books are good when you need a reference and some theory.
As for software, for an absolute beginer I really recomend Microsoft's Visual C++ because it makes it easy to do lots of trial and error which is really important part of early stages of learning to program. It also has a good detailed reference.
Free version available here: http://msdn.microsoft.com/vstudio/expres...
Keep in mind though there are other compilers and not all are compatable with ANSI Standard C++. g++ is very popular compiler on LINUX. Borland and Devshed are others for windows. But I have yet to see the user friendliness of Visual Studio in any other software for C++.
In strict sense parameters are passed by values only in C. For pass by reference we simulate it. IS this true
While passing by address, we pass the values of pointer variables i.e. addresses??
Also What is the difference between in call by reference and call by address in C. What abt C++??
In strict sense parameters are passed by values only in C. For pass by reference we simulate it. IS this true
You are correct..we pass the values of pointer variables...which in fact contain the address of where the real data is....so technically in C/C++ pointers are always 4-bytes in size despite the pointer type....it is when it is pointed to that you find the "real" type which can be things like char, int, byte, etc...
Call by Address and Call by Reference are synonymous with each other.
C++ has a newer feature over C where you can reference a variable as an "Alias" ... it's a much easier way than playing with pointers.
Reply:u r rite
dude
its the difference
in call by value value is copied to parameter
where as in reference address of the value is copied to parameter that can hold the value of address
Reply:I haven't programmed for a long time, but I remember you can pass by reference in C++. It's just a simple step that creates a substitute and has some very powerful advantages mainly when used with functions and in 'object oriented' programming. It's like giving a variable an 'alias'. It solves some problems that occur when passing by value.
I'm not sure if you can pass by reference in C (I don't think so).
Reply:Actually there is no call by reference concept in c,call by reference is in oops i think there is no diff in between call by ref in c++ and call by address in c
Also What is the difference between in call by reference and call by address in C. What abt C++??
In strict sense parameters are passed by values only in C. For pass by reference we simulate it. IS this true
You are correct..we pass the values of pointer variables...which in fact contain the address of where the real data is....so technically in C/C++ pointers are always 4-bytes in size despite the pointer type....it is when it is pointed to that you find the "real" type which can be things like char, int, byte, etc...
Call by Address and Call by Reference are synonymous with each other.
C++ has a newer feature over C where you can reference a variable as an "Alias" ... it's a much easier way than playing with pointers.
Reply:u r rite
dude
its the difference
in call by value value is copied to parameter
where as in reference address of the value is copied to parameter that can hold the value of address
Reply:I haven't programmed for a long time, but I remember you can pass by reference in C++. It's just a simple step that creates a substitute and has some very powerful advantages mainly when used with functions and in 'object oriented' programming. It's like giving a variable an 'alias'. It solves some problems that occur when passing by value.
I'm not sure if you can pass by reference in C (I don't think so).
Reply:Actually there is no call by reference concept in c,call by reference is in oops i think there is no diff in between call by ref in c++ and call by address in c
How does c being the constant unifying energy and mass derive from c being constant in all frames of reference
E=MC^2 is the bit in special relativity that laymen like me had heard of. After reading a bit on SR I understand (at a primitive level) the postulates and consequences re spacetime and EM radiation. The descriptions then jump to E=MC^2 without any explanation as to where it fits in and why c is again the critical factor. I am interested to kow what and where the link is connecting relativity as in c and frames of reference and relativity as in c and energy.
How does c being the constant unifying energy and mass derive from c being constant in all frames of reference
It is important to note that the result more correctly stated is as follows
E^2 = (mc^2)^2 + (pc)^2
from which the relation you quote results if the momentum p, is zero ie you are not moving, and you take the square root of both sides and keep the positive solution. So in no sense should any treatment jump straight to E = mc^2, it is a special case. You can find derivations online or in any college level physics textbook.
The key is that relativity joins space and time into one, as a result it also joins energy and momentum into one object, let me explain.
Energy conservation can be understood as due to the fact that an experiment performed today and an experiment performed tomorrow will yield the same result unless you change the experiment - called time invariance. Momentum conservation can be understood as due to the fact that an experiment performed at one end of a room will give the same results as at the other unless again you change the conditions. This is called spatial invariance. Well in our new spacetime prescription, we can't very well say that Energy conservation and momentum conservation are different, instead they are tied together in the above equation.
Reply:Assuming that c is constant in all reference frames, and assuming that space is homogeneous. isotropic, and translationally invariant lead directly to the necessity of the Lorentz transformations between frames. The LT's, in turn, required that the concept of kinetic energy be generalized from mv^2/2. Einstein did this and got an extra term that did not even depend on velocity v. It was, of course, mc^2. Despite his best efforts, it would not go away.
Reply:basically, because we don't know any better yet
How does c being the constant unifying energy and mass derive from c being constant in all frames of reference
It is important to note that the result more correctly stated is as follows
E^2 = (mc^2)^2 + (pc)^2
from which the relation you quote results if the momentum p, is zero ie you are not moving, and you take the square root of both sides and keep the positive solution. So in no sense should any treatment jump straight to E = mc^2, it is a special case. You can find derivations online or in any college level physics textbook.
The key is that relativity joins space and time into one, as a result it also joins energy and momentum into one object, let me explain.
Energy conservation can be understood as due to the fact that an experiment performed today and an experiment performed tomorrow will yield the same result unless you change the experiment - called time invariance. Momentum conservation can be understood as due to the fact that an experiment performed at one end of a room will give the same results as at the other unless again you change the conditions. This is called spatial invariance. Well in our new spacetime prescription, we can't very well say that Energy conservation and momentum conservation are different, instead they are tied together in the above equation.
Reply:Assuming that c is constant in all reference frames, and assuming that space is homogeneous. isotropic, and translationally invariant lead directly to the necessity of the Lorentz transformations between frames. The LT's, in turn, required that the concept of kinetic energy be generalized from mv^2/2. Einstein did this and got an extra term that did not even depend on velocity v. It was, of course, mc^2. Despite his best efforts, it would not go away.
Reply:basically, because we don't know any better yet
ALL arrays in C++ are passed as reference???
ALL arrays in C++ are passed as reference??
CAN ANY BODY TELL ME THAT IS IT TRUE??
ALL arrays in C++ are passed as reference???
yes, but you can pass individual elements within the array by value.
example:
char myarray[10] = "hello";
passbyvalue(myarray[0]);
//passes the letter "h" to the function
Reply:Yes. Arrays are always passed by Reference.
Reply:Yes arrays are passed by name
bloom
CAN ANY BODY TELL ME THAT IS IT TRUE??
ALL arrays in C++ are passed as reference???
yes, but you can pass individual elements within the array by value.
example:
char myarray[10] = "hello";
passbyvalue(myarray[0]);
//passes the letter "h" to the function
Reply:Yes. Arrays are always passed by Reference.
Reply:Yes arrays are passed by name
bloom
I am asking for a good and very advance C programming reference?
i need a refrence (book or e-book) include not only pointers, classes and ......
but also system calls, threads, hardware instruction, C over UNIX and ......
I am asking for a good and very advance C programming reference?
You can check free ebooks websites like http://myitcareer.org/
but also system calls, threads, hardware instruction, C over UNIX and ......
I am asking for a good and very advance C programming reference?
You can check free ebooks websites like http://myitcareer.org/
Confused about CONST keyword in C++ and Reference variable?
Consider following code:
void main()
{
int i=10;
int %26amp;ref1=i;
int %26amp; const ref2=i;
const int %26amp;ref3=i;
}
here...
What is difference between ref1 and ref3?
because
in code we can do:
ref1++;
ref2++;
but we can not do ref3++;It gives compile time error:Const obj can't be modified.
If any body know exact and only difference between
int %26amp;ref1=i;
and
int %26amp; const ref2=i;
Both ref1 and ref2 work as normal reference to integer variable.
Confused about CONST keyword in C++ and Reference variable?
ref3 is a const reference, which means you can't modify it. You are declaring the reference itself to be const.
ref2 is a regular reference. the const keyword in this case means what the reference is bound to (in this case the variable i) will not change, which is ALWAYS the case with references. the const keyword here is totally meaningless. syntactically it is correct which is why the compiler doesn't complain. but for all intents and purposes, ref1 and ref2 are exactly the same.
Reply:%26amp; means "by reference," which is different than "by value."
When you call a variable "by reference," you are asking for its location in memory. Therefore, you can change the value of the variable simply by calling it.
For example:
int byValue(test) {
test = 6;
return test;
}
int byReference(%26amp;test) {
test = 6;
return test;
}
int test = 4; // test = 4
test2 = byValue(test); // test = 6, test2 = 6
test2 = byReference(test); // test = 6, test2 = 6
So, it matters where we put the ampersand -- it needs to be right up against the variable we want to call by reference.
In the line int %26amp;ref1 = 1, we're setting the value of ref1 to be 1, and we're doing so by reference. For all practical purposes, it's the same as saying int ref1 = 1; since we're declaring the variable, it's new to memory; since it doesn't have a reference until we create it, asking to assign its value by reference is moot.
int %26amp; const ref2 = 1 throws an error because it's basically trying to create the same constant twice. Since it errors, ref2 does not become a constant but does get assigned a value of 1.
The reason ref3 can't be changed is that even though we are calling it by reference, we have declared it a constant, and that has priority.
Reply:CONST : Constant. These are basically values that will never change. Example of this would be
CONST INT PI = 3.14159
The value of PI is always going to be that so you don't want to change that.
REFERENCE VARIABLE: Reference variables are mainly used when you are passing variables from one function to another. You pass it by reference meaning you are passing the address of the variable location. This will ensure that whatever changes you make the variable will be made to the variable.
In your program you are doing
ref2++ which will give you the error since a CONST object is something that cannot have a changing value.
You need a variable for this instead.
void main()
{
int i=10;
int %26amp;ref1=i;
int %26amp; const ref2=i;
const int %26amp;ref3=i;
}
here...
What is difference between ref1 and ref3?
because
in code we can do:
ref1++;
ref2++;
but we can not do ref3++;It gives compile time error:Const obj can't be modified.
If any body know exact and only difference between
int %26amp;ref1=i;
and
int %26amp; const ref2=i;
Both ref1 and ref2 work as normal reference to integer variable.
Confused about CONST keyword in C++ and Reference variable?
ref3 is a const reference, which means you can't modify it. You are declaring the reference itself to be const.
ref2 is a regular reference. the const keyword in this case means what the reference is bound to (in this case the variable i) will not change, which is ALWAYS the case with references. the const keyword here is totally meaningless. syntactically it is correct which is why the compiler doesn't complain. but for all intents and purposes, ref1 and ref2 are exactly the same.
Reply:%26amp; means "by reference," which is different than "by value."
When you call a variable "by reference," you are asking for its location in memory. Therefore, you can change the value of the variable simply by calling it.
For example:
int byValue(test) {
test = 6;
return test;
}
int byReference(%26amp;test) {
test = 6;
return test;
}
int test = 4; // test = 4
test2 = byValue(test); // test = 6, test2 = 6
test2 = byReference(test); // test = 6, test2 = 6
So, it matters where we put the ampersand -- it needs to be right up against the variable we want to call by reference.
In the line int %26amp;ref1 = 1, we're setting the value of ref1 to be 1, and we're doing so by reference. For all practical purposes, it's the same as saying int ref1 = 1; since we're declaring the variable, it's new to memory; since it doesn't have a reference until we create it, asking to assign its value by reference is moot.
int %26amp; const ref2 = 1 throws an error because it's basically trying to create the same constant twice. Since it errors, ref2 does not become a constant but does get assigned a value of 1.
The reason ref3 can't be changed is that even though we are calling it by reference, we have declared it a constant, and that has priority.
Reply:CONST : Constant. These are basically values that will never change. Example of this would be
CONST INT PI = 3.14159
The value of PI is always going to be that so you don't want to change that.
REFERENCE VARIABLE: Reference variables are mainly used when you are passing variables from one function to another. You pass it by reference meaning you are passing the address of the variable location. This will ensure that whatever changes you make the variable will be made to the variable.
In your program you are doing
ref2++ which will give you the error since a CONST object is something that cannot have a changing value.
You need a variable for this instead.
C++: undefined reference to.....?
I have two objects A, and B. In A i have a function:
A::addB(B *b)
{
int bresult = b-%26gt;getResult();
..............
}
when compiled with g++ i get:
undefined reference to 'B::getResult()'
I didn't forget to include the header file for B
C++: undefined reference to.....?
When you get an "undefined reference" error, your problem won't be solved with #includes (assuming you are trying to link to a method defined in a .cpp, and all your #includes reference only .h files). The reason this is happening is that the object file in which B::getResult() is defined is not being found by the linker. So there is probably a file B.o that will have to be referenced in your linking line. Here's an abstraction of the g++ calls:
g++ -c A.cpp B.cpp
g++ -o myprogram A.o B.o
Reply:Include header for class B before using in class A.
Alternatively, this method will work.
// Header file
class B;
class A
{
public:
void addB(B *);
...
};
class B
{
public:
int getResult();
...
}
// Source file
void A::addB(B *b)
{
int bresult = b-%26gt;getResult();
...
}
That should fix your problem.
Reply:What does your compile command look like? You might have to make sure to G++ a.cpp b.cpp
Or something like that.
There are other causes: Is getResult() public on B?
A::addB(B *b)
{
int bresult = b-%26gt;getResult();
..............
}
when compiled with g++ i get:
undefined reference to 'B::getResult()'
I didn't forget to include the header file for B
C++: undefined reference to.....?
When you get an "undefined reference" error, your problem won't be solved with #includes (assuming you are trying to link to a method defined in a .cpp, and all your #includes reference only .h files). The reason this is happening is that the object file in which B::getResult() is defined is not being found by the linker. So there is probably a file B.o that will have to be referenced in your linking line. Here's an abstraction of the g++ calls:
g++ -c A.cpp B.cpp
g++ -o myprogram A.o B.o
Reply:Include header for class B before using in class A.
Alternatively, this method will work.
// Header file
class B;
class A
{
public:
void addB(B *);
...
};
class B
{
public:
int getResult();
...
}
// Source file
void A::addB(B *b)
{
int bresult = b-%26gt;getResult();
...
}
That should fix your problem.
Reply:What does your compile command look like? You might have to make sure to G++ a.cpp b.cpp
Or something like that.
There are other causes: Is getResult() public on B?
Where can i find a good reference site for c++ that is for free?
i have to do an assignment on c++ programmes. the reference book is very expensive for me and non of my friends have that book. i've searched the internet already but only finds a couple of good sites but it required payments. can anybody recommend something good for me?
Where can i find a good reference site for c++ that is for free?
Try this one. It has lots more than just C++
http://www.freeprogrammingresources.com/...
Reply:My husband is a programmer and recommended this free online book.
Good luck!
You want Thinking In C++
dogwood
Where can i find a good reference site for c++ that is for free?
Try this one. It has lots more than just C++
http://www.freeprogrammingresources.com/...
Reply:My husband is a programmer and recommended this free online book.
Good luck!
You want Thinking In C++
dogwood
What does the last c reference in circuit speed oc48c?
Circuit speed? Can you give a bit more information? Put this in context so we might have a clue.
C++ reference Parameter question?
I have to make a prgm. that uses 2 functions, 1 that reads in a time in mintues and seconds and another that displays the time like: 2:12:34.
Do you have any code suggestions, I'm stuck?
C++ reference Parameter question?
check out the time_t structure. and asctime() function in C.
after reading input from user (you could have one input line for hours, one for min, one for sec) you need to check the values (valid ranges 0..60 or 1..23). if any fail, re-read them all.
if they pass ranges, then place the values into a time_t and call asctime( ) - the output text will be nice and pretty.
Reply:theres a question similar to this in the archives.
i believe the complete code is provided in it as well.
its worth a search.
Reply:don't waste your time...out dated by 2 decades !!!!!!!!!!!!
Do you have any code suggestions, I'm stuck?
C++ reference Parameter question?
check out the time_t structure. and asctime() function in C.
after reading input from user (you could have one input line for hours, one for min, one for sec) you need to check the values (valid ranges 0..60 or 1..23). if any fail, re-read them all.
if they pass ranges, then place the values into a time_t and call asctime( ) - the output text will be nice and pretty.
Reply:theres a question similar to this in the archives.
i believe the complete code is provided in it as well.
its worth a search.
Reply:don't waste your time...out dated by 2 decades !!!!!!!!!!!!
In which ASTM standard is Reference Fuel C defined?
Reference Fuel C is required in many tests of rubber and polymer chemical resistance, but where is it defined?
In which ASTM standard is Reference Fuel C defined?
I believe ASTM D471 is your best bet. My recollection is that Reference Fuel C is composed of 50% isooctane and 50% toluene. Hope this helps.
In which ASTM standard is Reference Fuel C defined?
I believe ASTM D471 is your best bet. My recollection is that Reference Fuel C is composed of 50% isooctane and 50% toluene. Hope this helps.
Call by value || Call by reference for C++?
What is Call-by-reference semantics and Call-by-value semantics (in C++), and what's the difference between them.
Call by value || Call by reference for C++?
Call by value passes a parameter to the subroutine but if the subroutine modifies that parameter, it does not change the variable that was passed.
Call by reference passes the address of the actual parameter owned by the caller. If the called subroutine modifies that parameter, the calling routine will see the value of the parameter that was passed is changed.
Reply:if you want to modify a variable in a function then you should call that function the arguments of that function should be address of a variable that is called call by reference ( means that address).
void negative(int *np){*np=-(*np);}
If you call that function by value. there is no changes in that variable.
void negative(int np){np=-np;}
Try this with your c editor.
redbud
Call by value || Call by reference for C++?
Call by value passes a parameter to the subroutine but if the subroutine modifies that parameter, it does not change the variable that was passed.
Call by reference passes the address of the actual parameter owned by the caller. If the called subroutine modifies that parameter, the calling routine will see the value of the parameter that was passed is changed.
Reply:if you want to modify a variable in a function then you should call that function the arguments of that function should be address of a variable that is called call by reference ( means that address).
void negative(int *np){*np=-(*np);}
If you call that function by value. there is no changes in that variable.
void negative(int np){np=-np;}
Try this with your c editor.
redbud
How do I reference a dll in C# correctly?
There is this RCTDLL that I want to add as a reference to my project. But when I do add it to my project I get the error "A reference to C:\WINDOWS\WinSxS\x86_Microsoft.Windows.... cannot be added. Please make sure that the file is accessible, and that is a valid assembly or COM component"
How do I reference a dll in C# correctly?
First you need to know if this is a .net dll file, a COM component or a native win32 dll file.
You can easily add a reference to .net and COM dll files from References-%26gt;Add
If it's a native dll then you need to know which function you want to import and the prototype of the function (the name, parameter list and their types, return type).
You can use a tool such as Depends.Exe located
Visual Studio .NET Folder\Common7\Tools\Bin
which will list all the exported functions for native dlls. However, it doesn't give you the list of parameters! So you need the documentation for the dll to be able to use it's functions.
For example:
the lstrcat function in kernel32.dll would be imported like this:
[DllImport("kernel32.DLL")] private static extern int lstrcat
([MarshalAs(UnmanagedType.LPTStr)] string lpstring1,
[MarshalAs(UnmanagedType.LPTStr)] string lpstring2);
Reply:I think the dll is not a COM dll so you won't be able to add reference to it:
You can use dllImport to invoke the methods present in that Dll.
For this you must be knowing the signature of the methods that you want to call,
Go through the following link.
Calling Win32 DLLs in C# with P/Invoke
http://msdn.microsoft.com/msdnmag/issues...
I think this will solve your problem.
If still there for further help you can mail me,
i'll try to help if i can
How do I reference a dll in C# correctly?
First you need to know if this is a .net dll file, a COM component or a native win32 dll file.
You can easily add a reference to .net and COM dll files from References-%26gt;Add
If it's a native dll then you need to know which function you want to import and the prototype of the function (the name, parameter list and their types, return type).
You can use a tool such as Depends.Exe located
Visual Studio .NET Folder\Common7\Tools\Bin
which will list all the exported functions for native dlls. However, it doesn't give you the list of parameters! So you need the documentation for the dll to be able to use it's functions.
For example:
the lstrcat function in kernel32.dll would be imported like this:
[DllImport("kernel32.DLL")] private static extern int lstrcat
([MarshalAs(UnmanagedType.LPTStr)] string lpstring1,
[MarshalAs(UnmanagedType.LPTStr)] string lpstring2);
Reply:I think the dll is not a COM dll so you won't be able to add reference to it:
You can use dllImport to invoke the methods present in that Dll.
For this you must be knowing the signature of the methods that you want to call,
Go through the following link.
Calling Win32 DLLs in C# with P/Invoke
http://msdn.microsoft.com/msdnmag/issues...
I think this will solve your problem.
If still there for further help you can mail me,
i'll try to help if i can
Help with C# Function Reference Declaration Error???????????
please please help my friend with this if you can hes been working so hard on this but hes stuck :/
I am trying to write a C# program for class and I know very little about C#. I have defined my function below the includes:
void Echo_Keypress(ulong_t arg);
and I am using my function later in the program:
static void Echo_Keypress(ulong_t arg)
{
//do stuff
}
This is the error I am getting:
main.c: (.text+0x9a): undefined reference to `Echo_Keypress'
Does anyone know how to get around this error? Any help/info is greatly appreciated
Help with C# Function Reference Declaration Error???????????
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace jijo
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void Form1_KeyDown(object sender, KeyEventArgs e)
{
System.Windows.Forms.MessageBox.Show("Yo... press the key " + e.KeyCode.ToString());
}
}
}
Reply:Which of the two occurences of your function do you get the error on? I don't think in C# you have to declare a function like you would have to in C++.
Reply:See:
http://www.yoda.arachsys.com/csharp/para...
for the following topics:
Preamble: what is a reference type?
Further preamble: what is a value type?
Checking the preamble...
The different kinds of parameters
Value parameters
Reference parameters
Output parameters
Parameter arrays
Mini-glossary
Hope this helps.
Reply:Hi, You need not to declare your function as;
void Echo_keypress(ulong_t arg);
This is done normally in C++ or C style programming where you can declare functions before and give their definitions later on.
You just need to put your definition only, i.e.
static void Echo_keypress(ulong_t arg0
{
//do stuff
}
Also, as you are creating it as static, you will have to call it through class name directly, instead of creating a object first...
I am trying to write a C# program for class and I know very little about C#. I have defined my function below the includes:
void Echo_Keypress(ulong_t arg);
and I am using my function later in the program:
static void Echo_Keypress(ulong_t arg)
{
//do stuff
}
This is the error I am getting:
main.c: (.text+0x9a): undefined reference to `Echo_Keypress'
Does anyone know how to get around this error? Any help/info is greatly appreciated
Help with C# Function Reference Declaration Error???????????
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace jijo
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void Form1_KeyDown(object sender, KeyEventArgs e)
{
System.Windows.Forms.MessageBox.Show("Yo... press the key " + e.KeyCode.ToString());
}
}
}
Reply:Which of the two occurences of your function do you get the error on? I don't think in C# you have to declare a function like you would have to in C++.
Reply:See:
http://www.yoda.arachsys.com/csharp/para...
for the following topics:
Preamble: what is a reference type?
Further preamble: what is a value type?
Checking the preamble...
The different kinds of parameters
Value parameters
Reference parameters
Output parameters
Parameter arrays
Mini-glossary
Hope this helps.
Reply:Hi, You need not to declare your function as;
void Echo_keypress(ulong_t arg);
This is done normally in C++ or C style programming where you can declare functions before and give their definitions later on.
You just need to put your definition only, i.e.
static void Echo_keypress(ulong_t arg0
{
//do stuff
}
Also, as you are creating it as static, you will have to call it through class name directly, instead of creating a object first...
How can we reference c# code into vb? Please help!?
I have some problem when i try to reference C# code into vb.net
Intellisense does not show me anything
for eg. a c# class 'Microsoft.Samples'
When i type 'Microsoft.' then intellisense does not show me samples.I have imported the class file into my project.
Please give suggestions...
How can we reference c# code into vb? Please help!?
Did you add the dll to the project, too? Go to References, right click, and look for the dll you want to add.
Then use the "Imports" statement.
Reply:See these links
http://www.dnzone.com/forum/topic.asp?to...
http://www.thescripts.com/forum/thread25...
Reply:How can we reference c# code into vb?
Intellisense does not show me anything
for eg. a c# class 'Microsoft.Samples'
When i type 'Microsoft.' then intellisense does not show me samples.I have imported the class file into my project.
Please give suggestions...
How can we reference c# code into vb? Please help!?
Did you add the dll to the project, too? Go to References, right click, and look for the dll you want to add.
Then use the "Imports" statement.
Reply:See these links
http://www.dnzone.com/forum/topic.asp?to...
http://www.thescripts.com/forum/thread25...
Reply:How can we reference c# code into vb?
Where can I find a C# Reference Sheet?
Long time answerer, first time asker... (I've always wanted to say that)...
I'm still relativily new to programming in C# and I have a few books on the subject. I'm looking for a quick reference chart with some basic commands that I need on it (instead of flipping through pages looking).
Can anyone supply a couple links?
Thanks for your help!
Jason
Where can I find a C# Reference Sheet?
Assuming that you need it for Microsoft platforms, the best resource is MSDN.
C# as language on MSDN:
http://msdn.microsoft.com/vcsharp/progra...
You probably also need .NET Framework Library
http://msdn.microsoft.com/library/defaul...
Reply:Mr, The people who wrote the books you have read/reading are professionals in the field of the programming language you are talking about i.e c# and the only way to achieve your goal is to read and understand each chapter very well. i once did what you are trying to do, but later on i noticed that most questions people ask me, or most difficulties i face are somewhere in those pages that i skipped. Try taking your time to achieve your goal and not looking for a shortcut. Here is a Link to a Nice E-book Tutorial on c# http://www.intelligentedu.com/blogs/post...
Reply:Yep MSDN. You can download the libraries as well....so....
sundew
I'm still relativily new to programming in C# and I have a few books on the subject. I'm looking for a quick reference chart with some basic commands that I need on it (instead of flipping through pages looking).
Can anyone supply a couple links?
Thanks for your help!
Jason
Where can I find a C# Reference Sheet?
Assuming that you need it for Microsoft platforms, the best resource is MSDN.
C# as language on MSDN:
http://msdn.microsoft.com/vcsharp/progra...
You probably also need .NET Framework Library
http://msdn.microsoft.com/library/defaul...
Reply:Mr, The people who wrote the books you have read/reading are professionals in the field of the programming language you are talking about i.e c# and the only way to achieve your goal is to read and understand each chapter very well. i once did what you are trying to do, but later on i noticed that most questions people ask me, or most difficulties i face are somewhere in those pages that i skipped. Try taking your time to achieve your goal and not looking for a shortcut. Here is a Link to a Nice E-book Tutorial on c# http://www.intelligentedu.com/blogs/post...
Reply:Yep MSDN. You can download the libraries as well....so....
sundew
C# reference book?
HI, I am looking for a good c# reference book to keep beside me while I am programming, can you recommend any?
C# reference book?
Beginning Visual C# 2005 (for beginner user)
http://www.amazon.com/Beginning-Visual-2...
Professional C# 2005 (for advanced user)
http://www.amazon.com/Professional-2005-...
Visual C# 2005 How to Program (for newcomer user)
http://www.amazon.com/Visual-2005-How-Pr...
Reply:The C programming language by Kernighan and Ritchie
Reply:I recommend this book.
http://www.amazon.com/Microsoft-Visual-2...
Covers the major stuff.
C# reference book?
Beginning Visual C# 2005 (for beginner user)
http://www.amazon.com/Beginning-Visual-2...
Professional C# 2005 (for advanced user)
http://www.amazon.com/Professional-2005-...
Visual C# 2005 How to Program (for newcomer user)
http://www.amazon.com/Visual-2005-How-Pr...
Reply:The C programming language by Kernighan and Ritchie
Reply:I recommend this book.
http://www.amazon.com/Microsoft-Visual-2...
Covers the major stuff.
C++ reference to object, passing to constructors?
Hi everyone, I'm using some code (see below)
and I want to save the reference "%26amp;AdminRef" so that other functions in my class can use it, how should I do this?
(Sorry if this is a nooby question, just starting out and playing with C++)
C++ reference to object, passing to constructors?
class Player {
//Variables
string Name;
int Level;
int TotalHealth;
int CurrentHealth;
int WeaponID;
int ArmorID;
GameManager *Admin;
Player::Player(GameManager *AdminRef) {
Admin = AdminRef;
}
//Functions
void Player::Attack(string Type) {
AdminRef-%26gt;Attack("Player", Type);
}
}
int main()
{
GameManager Admin;
MainPlayer Player(%26amp;Admin);
return 0;
}
Make sure you initialize Admin in main before you pass it in to Player().
Reply:I tend to use pointers rather than references, but this is what I'd do:
class {
// Allocate a pointer for general use
GameAdmin* m_AdminRef
...
Player::Player( GameAdmin *AdminRef )
{
m_AdminRef = AdminRef;
}
void Player::Attack(string Type) {
m_AdminRef-%26gt;Attack("Player", Type);
} // end of class
This might also work as a reference; I'm not that up on them.
Hope that helps.
Reply:Just declare the reference in the class, so along with all your int and stuff write a
GameManager %26amp;adminRef
And in your constructor change it to adminRef = AdminRef to make your class's copy of adminRef equal to whatever you put it through your constructor.
Then you can access adminRef like any other variable in your class.
and I want to save the reference "%26amp;AdminRef" so that other functions in my class can use it, how should I do this?
(Sorry if this is a nooby question, just starting out and playing with C++)
C++ reference to object, passing to constructors?
class Player {
//Variables
string Name;
int Level;
int TotalHealth;
int CurrentHealth;
int WeaponID;
int ArmorID;
GameManager *Admin;
Player::Player(GameManager *AdminRef) {
Admin = AdminRef;
}
//Functions
void Player::Attack(string Type) {
AdminRef-%26gt;Attack("Player", Type);
}
}
int main()
{
GameManager Admin;
MainPlayer Player(%26amp;Admin);
return 0;
}
Make sure you initialize Admin in main before you pass it in to Player().
Reply:I tend to use pointers rather than references, but this is what I'd do:
class {
// Allocate a pointer for general use
GameAdmin* m_AdminRef
...
Player::Player( GameAdmin *AdminRef )
{
m_AdminRef = AdminRef;
}
void Player::Attack(string Type) {
m_AdminRef-%26gt;Attack("Player", Type);
} // end of class
This might also work as a reference; I'm not that up on them.
Hope that helps.
Reply:Just declare the reference in the class, so along with all your int and stuff write a
GameManager %26amp;adminRef
And in your constructor change it to adminRef = AdminRef to make your class's copy of adminRef equal to whatever you put it through your constructor.
Then you can access adminRef like any other variable in your class.
Can a C++ reference hold a reference to a child of it's class?
For C++ gurus.
Consider the following code snippets:
ostream %26amp; outfile=cout; // assign stdout to a reference of ostream
Then I may want to do something like this:
ofstream* alternate_op=new ofstream("my_output.txt");
outfile=(ostream %26amp;) *alternate_op;
Now outfile points to my alternate output file instead of stdout. Fine. In MS Visual C++ 6.0 this works out just the way I want it. But other compilers (such as MingW for Windows) complain with messages like:
741 C:\Dev-Cpp\include\c++\3.4.2\bits\ios_ba... `std::ios_base%26amp; std::ios_base::operator=(const std::ios_base%26amp;)' is private
So, is my solution the best one? Or is there a better way? I want to be able to dynamically use either stdout (cout) or my own o/p file stream along with operator%26lt;%26lt; to format output without a lot of fooling around about which one I'm really using. And I'd like my solution to be as portable between compilers as possible.
Can a C++ reference hold a reference to a child of it's class?
Biting my tongue and not taking an obligatory swipe at VC.
Assuming you can, just change the reference to a pointer and you are good to go.
int main ()
{
ostream* outfile = %26amp;cout; // assign stdout to a POINTER to ostream
*outfile %26lt;%26lt; "Hello\n";
ofstream* alternate_op=new ofstream("my_output.txt");
outfile = alternate_op;
*outfile %26lt;%26lt; "World" %26lt;%26lt; endl;
}
Reply:You could run into a dangling pointer problem.
Reply:In C++ you can't reassign a reference. I don't know why VC6 allows you to do it, but it shouldn't. When you assign to a reference, you actually assign to the value being referenced. In this case your code is trying to change the value of cout.
Consider the following code snippets:
ostream %26amp; outfile=cout; // assign stdout to a reference of ostream
Then I may want to do something like this:
ofstream* alternate_op=new ofstream("my_output.txt");
outfile=(ostream %26amp;) *alternate_op;
Now outfile points to my alternate output file instead of stdout. Fine. In MS Visual C++ 6.0 this works out just the way I want it. But other compilers (such as MingW for Windows) complain with messages like:
741 C:\Dev-Cpp\include\c++\3.4.2\bits\ios_ba... `std::ios_base%26amp; std::ios_base::operator=(const std::ios_base%26amp;)' is private
So, is my solution the best one? Or is there a better way? I want to be able to dynamically use either stdout (cout) or my own o/p file stream along with operator%26lt;%26lt; to format output without a lot of fooling around about which one I'm really using. And I'd like my solution to be as portable between compilers as possible.
Can a C++ reference hold a reference to a child of it's class?
Biting my tongue and not taking an obligatory swipe at VC.
Assuming you can, just change the reference to a pointer and you are good to go.
int main ()
{
ostream* outfile = %26amp;cout; // assign stdout to a POINTER to ostream
*outfile %26lt;%26lt; "Hello\n";
ofstream* alternate_op=new ofstream("my_output.txt");
outfile = alternate_op;
*outfile %26lt;%26lt; "World" %26lt;%26lt; endl;
}
Reply:You could run into a dangling pointer problem.
Reply:In C++ you can't reassign a reference. I don't know why VC6 allows you to do it, but it shouldn't. When you assign to a reference, you actually assign to the value being referenced. In this case your code is trying to change the value of cout.
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