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Formal parameters are the parameters as they are known in the function definition. Actual parameters (also known as arguments) are what are passed by the caller. For example, in the following code, a and b are the formal parameters, and x and y are the actual parameters:

int max(int a, int b) {
if (a > b) return a;
else return b;
}

int m = max(x, y);

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14y ago
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15y ago

The arguments passed to the functions while the function is called is known as the actual arguments, whereas the arguments declared in the function header is called as formal arguments.

Ex. Suppose sum() is a function.

int sum(int x, int y) /*Here x and y are called formal arguments*/

{...}

void main()

{

int ans;

....

ans = sum(3,5); /*Here the arguments 3 and 5 are called actual arguments*/

...

getch();

}

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12y ago

1> the parameters used in prototypes and function definitions are called formal parameters and

2>those used in function calls are called actual parameters.actual parameters used in a calling statement may be simple constants.

Example:

int main()

{

int a,b,c;

int add(int,int);

c=add(a,b);//actual parameter

printf("%d",c);

getch();

}

int add(int e,int f) //formal parameter

{ printf("enter the no");

scanf("%d%d",&e,&f);

return e+f;

}

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10y ago

Formal arguments are the arguments used locally by a function. Actual arguments are the arguments that were passed to the function by the caller.

Consider the following:

void foo(int formal)

{

// formal is local to foo, and is a copy of actual

}

void bar(int& formal)

{

// formal is local to bar, and is a reference to actual (an alternate name for actual)

}

int main()

{

int actual = 42;

// actual is local to main

foo(actual); // pass actual to foo by value

bar(actual); // pass actual to bar by reference

}

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11y ago

Formal arguments are the arguments in the definition of a function.

Actual arguments are the arguments provided to the function when you call it.

Example:

float divide(float arg1, float arg2) // Here, arg1 and arg2 are formal arguments.

{

return arg1/arg2;

}

int main(void)

{

float num1 = 4.0f;

float num2 = 2.0f;

float result = divide(num1, num2); // Here, num1 and num2 are actual arguments.

float result2 = divide(16.0f, 8.0f); // Note that 16.0f and 8.0f are also actual arguments.

return 0;

}

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Q: What is the difference between actual and formal argument in c plus plus?
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Explain the difference between an argument and a parameter Use a C plus plus program segment to illustrate your answer?

In C++ there is no such thing as a parameter, there are only arguments, both actual and formal. Some languages use the term parameter to mean a formal argument and argument to mean an actual argument, while others reverse the meanings completely. Some languages make no distinction at all and use the terms parameter and argument interchangeably. However, C++ is quite clear on this: actual arguments are the names that you pass to a function, while formal arguments are the names received by the function. Even so, you will still encounter incorrect usage of the terms parameter and arguments, even by C++ experts (myself included!) The following example code demonstrates the difference between an actual argument and a formal argument, as the terms apply in C++: int foo(int formal) { return(formal*2); } void bar(int& formal) { formal*=2; } int main() { int actual=1; actual = foo(actual); bar(actual); return(0); } The function foo() declares a formal argument by value while bar() declares a formal argument by reference. In main() we declare a variable with the name actual and pass this actual argument to both functions in turn. When we pass actual to foo(), the value of actual is assigned to formal. Since formal is a copy of actual, they are separate names with separate values (initially they will have the same value of course). Thus any changes made to formal will have no effect on actual, hence we must assign the return value from foo() to actual in main(), in order to record the change made by foo(). When we pass actual to bar(), a reference to actual is assigned to formal. A reference is simply an alternate name for the same argument, however the name actual is not visible to bar(), so they are still separate names, but they always have the same value. Thus any changes to formal will affect actual, thus there is no need to assign any return value to record the change.


What is the difference between parameters and arguments in VB?

In programming languages, a parameter and an argument are the same thing; there is no actual difference between the two. Although a few languages do differentiate between an actual argument and a formal argument by calling one a parameter and the other an argument (or vice versa), the terms are universally interchangeable. That is; there is no single definition that applies to any one language, including Visual Basic. The language may have a convention, but there's no reason to follow that convention. Personally, I prefer the term argument and use the terms formal argument and actual argument whenever I need to specifically differentiate one from the other. In this way I can refer to them in a consistent but language-agnostic manner. Only a Pedant would argue that the terms parameter and argument have a specific meaning to a specific language, even when the creators of that language use the terms interchangeably themselves. To clarify, an actual argument is the argument being passed to a function while a formal argument is the argument that is used by the function. The two will always have the same value, but they are not the same argument. For instance, consider the following function definition: f (int a) { print a*2 } Whether we regard 'a' as being a parameter or an argument is immaterial -- it is a formal argument or formal parameter, whichever you prefer. The meaning is clarified by using the word "formal". Now consider the calling code: b = 42 f (b) Here, b is the actual argument (or actual parameter) being passed to the function f. Note that a and b are not the same variable or reference. That alone means there is no reason to differentiate them; the meaning of argument or parameter is implied by the context alone. It doesn't matter whether the function uses pass by value or pass by reference semantics. When passing arguments by value, a is simply a copy of b (independent variables with the same value). When passing by reference, a refers to the same memory address as b (a is an alias for b). In either case, the function uses the formal argument named a while the calling code uses the actual argument named b. In other words, the names are only accessible from within the scope in which they are declared, even if they refer to the same memory address. Of course, a function may pass one of its formal arguments to another function. Thus with respect to the calling function, its formal argument becomes an actual argument to the function being called.


In python are actual and formal parameters matched up by position or name?

When we invoke a function, we pass the actual arguments in the same order specified by the function's formal arguments, thus it is the relative position that determines how they are matched. Note that actual parameter names are within the scope of the calling code while formal parameter names are scoped to the function in which they are declared. The calling code has no access to the formal argument names, and the function may or may not have access to the actual argument names. Python uses the pass-by-object paradigm: if the object being passed is immutable, then it is passed by value (the formal parameter is assigned a copy of the object's value), otherwise it is passed by reference (in which case the formal argument becomes an alternative name for the actual argument).


How structure is passed to function using structure pointer?

When you pass an object to a function you are not actually passing the object, you are only passing the object's value. This is what is meant by the term pass by value.When passing a value to a function there are actually two objects involved in the exchange: the actual argument (the object that is being passed) and the formal argument (the object used by the function). When we call a function that accepts one or more arguments (also known as parameters), the value of the actual argument is assigned to the corresponding formal argument. Thus the formal argument is a copy of the actual argument and any changes made to the formal argument will have no effect upon the actual argument.When the formal argument is a pointer, however, the value we pass is a memory address. The actual argument can either be a pointer of the same type or we can take the address of an object of the same type using the address-of operator and pass that. Either way, the value we pass is a memory address. We call this pass by reference even though the address is actually being passed by value. Passing by reference means that the formal argument and the actual argument both refer to the same object and offers an efficient means of passing large objects that are too expensive to copy. This includes most structures and unions and all arrays. Note that arrays implicitly decay to pointers and therefore cannot be passed by value. Structures and unions can be passed by value, but if they are larger than a pointer (in bytes) passing by reference is more efficient.There are four different ways to declare a formal argument as a pointer:mutable pointer to mutable typemutable pointer to constant typeconstant pointer to mutable typeconstant pointer to constant typeIdeally, functions should declare formal pointer arguments using methods 2 or 4. Both point to constant types so this gives the caller an assurance that the function has no side effects upon the object being passed by reference. Functions that use methods 1 or 3 should be regarded as having side-effects upon the object being referred to. This can be desirable for efficiency reasons, however returning values via arguments (also known as output parameters) should be avoided whenever possible.Note that it makes no difference if the formal pointer argument is mutable or constant because the formal and actual arguments are still separate objects. Constant formal arguments are only of relevance to the function designer, they are of no importance to the caller. This is true of all values passed to functions whether the value is a memory address or not. What is important to the caller of a by reference function is whether or not the object being pointed at is declared constant or not.


Formal and Actual Arguments?

The actual arguments (we call them parameters) to a function are the original copies in the caller's address space. The function prolog code provided by the compiler provides for making copies of all of the parameters. These copies are called the formal parameters. In C and C++, the default calling convention is call by value, which means that the called function only has access to the formal copy. Optionally, you can call by reference, passing instead the address of the actual parameter. Using dereference notation, the called function then has access to the actual parameter, and the formal parameter is simply its address. One of the things that sometimes confuses people is the name of the parameter. You might, for instance, call something alpha in you main function. It is called alpha, and alpha means the memory location of alpha. In the function, however, you can call the parameter something else, perhaps beta. Within the context of the called function, beta contains the value of or the address of alpha, but it is not alpha, it is beta. To make matters worse, you can have another alpha within a block, or within the function, and that is certainly not related at all to the original alpha. Recommendation: Always call an object by consistent names. This way, you won't get into scoping rules trouble.

Related questions

Explain the difference between an argument and a parameter Use a C plus plus program segment to illustrate your answer?

In C++ there is no such thing as a parameter, there are only arguments, both actual and formal. Some languages use the term parameter to mean a formal argument and argument to mean an actual argument, while others reverse the meanings completely. Some languages make no distinction at all and use the terms parameter and argument interchangeably. However, C++ is quite clear on this: actual arguments are the names that you pass to a function, while formal arguments are the names received by the function. Even so, you will still encounter incorrect usage of the terms parameter and arguments, even by C++ experts (myself included!) The following example code demonstrates the difference between an actual argument and a formal argument, as the terms apply in C++: int foo(int formal) { return(formal*2); } void bar(int& formal) { formal*=2; } int main() { int actual=1; actual = foo(actual); bar(actual); return(0); } The function foo() declares a formal argument by value while bar() declares a formal argument by reference. In main() we declare a variable with the name actual and pass this actual argument to both functions in turn. When we pass actual to foo(), the value of actual is assigned to formal. Since formal is a copy of actual, they are separate names with separate values (initially they will have the same value of course). Thus any changes made to formal will have no effect on actual, hence we must assign the return value from foo() to actual in main(), in order to record the change made by foo(). When we pass actual to bar(), a reference to actual is assigned to formal. A reference is simply an alternate name for the same argument, however the name actual is not visible to bar(), so they are still separate names, but they always have the same value. Thus any changes to formal will affect actual, thus there is no need to assign any return value to record the change.


Sample program in c plus plus with parameter?

C++ doesn't have parameters it has arguments, both formal and actual. Actual arguments are the arguments you pass to a function. Formal arguments are the arguments used by the function and which are treated as local variables within the function body. Formal arguments always fall from scope when the function returns. In order for a function to make changes to the actual argument you you can either return the formal argument by value and assign the function to the actual argument upon return, or you can pass the argument by reference. In the former case, the returned value is temporary. If the function is not assigned to the actual argument, the temporary value falls from scope. In the latter case, the actual and formal arguments both refer to the same object through separate names (aliases). Thus any operations performed on the formal argument will affect the actual argument (they are one and the same object). Example: // Forward declarations. int byval (int); void byref (int&); int main() { int actual = 42; byval (actual); // The byval formal argument is no longer in scope. // Although a temporary value of 84 was returned, // it wasn't assigned to anything and is no longer // available. // The actual argument still has the value 42. actual = byval (actual); // The byval formal argument is no longer in scope, // however, its value was returned and assigned // to the actual argument. // The actual argument now has the value 84. byref (actual); // The formal argument and the actual argument are // one and the same argument. // The actual argument now has the value 42. } int byvalue(int formal) { formal *= 2; return formal; } // The formal argument no longer exists, but its value // was pushed into the function's return address. That // value will cease to exist unless the caller immediately // assigns the function's return value to a variable. void byref(int& formal) { formal /= 2; } // The formal argument no longer exists and nothing // was pushed onto the function's return address. // However, formal was just an alias for the actual // argument, thus the actual argument has already // been updated.


What is the difference between parameters and arguments in VB?

In programming languages, a parameter and an argument are the same thing; there is no actual difference between the two. Although a few languages do differentiate between an actual argument and a formal argument by calling one a parameter and the other an argument (or vice versa), the terms are universally interchangeable. That is; there is no single definition that applies to any one language, including Visual Basic. The language may have a convention, but there's no reason to follow that convention. Personally, I prefer the term argument and use the terms formal argument and actual argument whenever I need to specifically differentiate one from the other. In this way I can refer to them in a consistent but language-agnostic manner. Only a Pedant would argue that the terms parameter and argument have a specific meaning to a specific language, even when the creators of that language use the terms interchangeably themselves. To clarify, an actual argument is the argument being passed to a function while a formal argument is the argument that is used by the function. The two will always have the same value, but they are not the same argument. For instance, consider the following function definition: f (int a) { print a*2 } Whether we regard 'a' as being a parameter or an argument is immaterial -- it is a formal argument or formal parameter, whichever you prefer. The meaning is clarified by using the word "formal". Now consider the calling code: b = 42 f (b) Here, b is the actual argument (or actual parameter) being passed to the function f. Note that a and b are not the same variable or reference. That alone means there is no reason to differentiate them; the meaning of argument or parameter is implied by the context alone. It doesn't matter whether the function uses pass by value or pass by reference semantics. When passing arguments by value, a is simply a copy of b (independent variables with the same value). When passing by reference, a refers to the same memory address as b (a is an alias for b). In either case, the function uses the formal argument named a while the calling code uses the actual argument named b. In other words, the names are only accessible from within the scope in which they are declared, even if they refer to the same memory address. Of course, a function may pass one of its formal arguments to another function. Thus with respect to the calling function, its formal argument becomes an actual argument to the function being called.


What are the difference between colloquial and formal English?

what is the difference between colloquial and formal English


In python are actual and formal parameters matched up by position or name?

When we invoke a function, we pass the actual arguments in the same order specified by the function's formal arguments, thus it is the relative position that determines how they are matched. Note that actual parameter names are within the scope of the calling code while formal parameter names are scoped to the function in which they are declared. The calling code has no access to the formal argument names, and the function may or may not have access to the actual argument names. Python uses the pass-by-object paradigm: if the object being passed is immutable, then it is passed by value (the formal parameter is assigned a copy of the object's value), otherwise it is passed by reference (in which case the formal argument becomes an alternative name for the actual argument).


What is the difference between formal and informal speech?

A fallacy is a mistaken belief. A formal fallacy is one in which the argument itself is wrong, which makes it always wrong. An informal fallacy is one in which the reasoning is wrong, not the form of the argument itself.


What is pass by value in c functions?

Pass by value is a semantic that describes the way in which the actual argument in the calling code is assigned to the corresponding formal argument of the function being called. In pass by value, the actual argument and the corresponding formal argument are independent of each other; changing the value of the formal argument has no effect whatsoever upon the actual argument's value. In other words, the function receives a copy of the actual argument's value, never the actual argument itself. In C, all arguments are passed by value. However, when the formal argument is declared a pointer, we are effectively declaring a pass by reference semantic. The formal and actual arguments are still independent of each other (the formal argument's pointer value can still be changed without affecting the actual argument's pointer value), but if the formal argument and the actual argument both refer to the same object, changing that object's value via the function changes the same value in the caller. Pass by reference is useful when the value being passed is large or complex and cannot be implicitly or easily copied, such as an array or data structure. Pass by reference can also be used to return a value to the caller via an "output parameter", thus allowing a function to return more than one value. [Object-oriented programmers will detest the use of output parameters, citing bad programming practice (or poor style), but in C, it is not only desirable to use them to maintain efficiency, it is largely unavoidable. Object-oriented languages have highly efficient move constructors and move assignment operators, but C does not and copying large structures unnecessarily is detrimental to performance.]


Difference between formal and informal organisation?

difference between formal organization structure and informal organization structure.


The difference between formal and informal risk assessment?

explain the difference between formal and informal risk assessments


What is the difference between formal and informal observations?

....


What is the difference between formal and informal rhythm in arts?

formal and informal rhythm


What is formal debate?

A formal debate is an argument between two individuals that is bound by rules and the participants conduct themselves professionally. Some formal debates are competitions that are judged to have a winner.