Note
Access to this page requires authorization. You can try signing in or changing directories.
Access to this page requires authorization. You can try changing directories.
Illustrates how to use trigonometry (sin, cos, tan, and so on) functions in Visual C++.
// acos
template<class T>
inline valarray<T> acos(
const valarray<T>& x
);
// asin
template<class T>
inline valarray<T> asin(
const valarray<T>& x
);
// atan
template<class T>
inline valarray<T> atan(
const valarray<T>& x
);
// atan2
template<class T>
inline valarray<T> atan2(
const valarray<T>& x,
const valarray<T>& y
);
template<class T>
inline valarray<T> atan2(
const valarray<T> x,
const T& y
);
template<class T>
inline valarray<T> atan2(
const T& x,
const valarray<T>& y
);
// cos
template<class T>
inline valarray<T> cos(
const valarray<T>& x
);
// cosh
template<class T>
inline valarray<T> cosh(
const valarray<T>& x
);
// sin
template<class T>
inline valarray<T> sin(
const valarray<T>& x
);
// sinh
template<class T>
inline valarray<T> sinh(
const valarray<T>& x
);
// tan
template<class T>
inline valarray<T> tan(
const valarray<T>& x
);
// tanh
template<class T>
inline valarray<T> tanh(
const valarray<T>& x
);
Example
Note
The class/parameter names in the prototype do not match the version in the header file. Some have been modified to improve readability.
// trig.cpp
// compile with: /EHsc
// Illustrates the use of STL trigonometry functions.
// Functions:
// acos, asin, atan, atan2, cos, cosh, sin, sinh, tan, tanh
//////////////////////////////////////////////////////////////////////
#include <iostream> // for i/o functions
#include <valarray> // for valarray
#include <cmath> // for trigonometry functions
using namespace std ;
#define ARRAY_SIZE 3 // array size
int main()
{
// Initialize val_array to values -1, 0 and 1.
valarray<double> val_array(ARRAY_SIZE);
int i;
for (i = 0; i < ARRAY_SIZE; i+)
val_array[i] = i - 1;
// Display the size of val_array.
cout << "Size of val_array = " << val_array.size() << endl;
// Display the values of val_array before calling any trigonometry
// functions.
cout << "The values in val_array:" << endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << val_array[i];
cout << " ]" << endl << endl;
// Initialize rev_valarray that is the reverse of val_array.
valarray<double> rev_valarray(ARRAY_SIZE);
for (i = 0; i < ARRAY_SIZE; i+)
rev_valarray[i] = val_array[ARRAY_SIZE - i - 1];
// Display the size of rev_valarray.
cout << "Size of rev_valarray = " << rev_valarray.size() << endl;
// Display the values of rev_valarray.
cout << "The values in rev_valarray:" << endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rev_valarray[i];
cout << " ]" << endl << endl;
// rvalue_array to hold the return value from calling the trigonometry
// functions.
valarray<double> rvalue_array;
// ----------------------------------------------------------------
// acos() - display the result of rvalue_array
// ----------------------------------------------------------------
rvalue_array = acos(val_array);
cout << "The result after calling acos():" << endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rvalue_array[i];
cout << " ]" << endl << endl;
// ----------------------------------------------------------------
// asin() - display the result of rvalue_array
// ----------------------------------------------------------------
rvalue_array = asin(val_array);
cout << "The result after calling asin():" << endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rvalue_array[i];
cout << " ]" << endl << endl;
// ----------------------------------------------------------------
// atan() - display the result of rvalue_array
// ----------------------------------------------------------------
rvalue_array = atan(val_array);
cout << "The result after calling atan():" << endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rvalue_array[i];
cout << " ]" << endl << endl;
// ----------------------------------------------------------------
// atan2() - display the result of rvalue_array
// ----------------------------------------------------------------
// This template function returns an object of class valarray<T>,
// each of whose elements at I is the arctangent of x[I] / y[I].
rvalue_array = atan2(val_array, rev_valarray);
cout << "The result after calling atan2(val_array, rev_valarray):"
<< endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rvalue_array[i];
cout << " ]" << endl << endl;
// This template function stores in element I the arctangent of
// x[I] / y.
rvalue_array = atan2(val_array, 3.1416);
cout << "The result after calling atan2(val_array, 3.1416):"
<< endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rvalue_array[i];
cout << " ]" << endl << endl;
// This template function stores in element I the arctangent of
// x / y[I].
rvalue_array = atan2(3.1416, val_array);
cout << "The result after calling atan2(3.1416, val_array):"
<< endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rvalue_array[i];
cout << " ]" << endl << endl;
// ----------------------------------------------------------------
// cos() - display the result of rvalue_array
// ----------------------------------------------------------------
rvalue_array = cos(val_array);
cout << "The result after calling cos():" << endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rvalue_array[i];
cout << " ]" << endl << endl;
// ----------------------------------------------------------------
// cosh() - display the result of rvalue_array
// ----------------------------------------------------------------
rvalue_array = cosh(val_array);
cout << "The result after calling cosh():" << endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rvalue_array[i];
cout << " ]" << endl << endl;
// ----------------------------------------------------------------
// sin() - display the result of val_array
// ----------------------------------------------------------------
rvalue_array = sin(val_array);
cout << "The result after calling sin():" << endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rvalue_array[i];
cout << " ]" << endl << endl;
// ----------------------------------------------------------------
// sinh() - display the result of val_array
// ----------------------------------------------------------------
rvalue_array = sinh(val_array);
cout << "The result after calling sinh():" << endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rvalue_array[i];
cout << " ]" << endl << endl;
// ----------------------------------------------------------------
// tan() - display the result of val_array
// ----------------------------------------------------------------
rvalue_array = tan(val_array);
cout << "The result after calling tan():" << endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rvalue_array[i];
cout << " ]" << endl << endl;
// ----------------------------------------------------------------
// tanh() - display the result of val_array
// ----------------------------------------------------------------
rvalue_array = tanh(val_array);
cout << "The result after calling tanh():" << endl << "[";
for (i = 0; i < ARRAY_SIZE; i+)
cout << " " << rvalue_array[i];
cout << " ]" << endl;
}
Size of val_array = 3 The values in val_array: [ -1 0 1 ] Size of rev_valarray = 3 The values in rev_valarray: [ 1 0 -1 ] The result after calling acos(): [ 3.14159 1.5708 0 ] The result after calling asin(): [ -1.5708 0 1.5708 ] The result after calling atan(): [ -0.785398 0 0.785398 ] The result after calling atan2(val_array, rev_valarray): [ -0.785398 0 2.35619 ] The result after calling atan2(val_array, 3.1416): [ -0.308168 0 0.308168 ] The result after calling atan2(3.1416, val_array): [ 1.87896 1.5708 1.26263 ] The result after calling cos(): [ 0.540302 1 0.540302 ] The result after calling cosh(): [ 1.54308 1 1.54308 ] The result after calling sin(): [ -0.841471 0 0.841471 ] The result after calling sinh(): [ -1.1752 0 1.1752 ] The result after calling tan(): [ -1.55741 0 1.55741 ] The result after calling tanh(): [ -0.761594 0 0.761594 ]
Requirements
Header: <valarray>
See Also
Concepts
Standard Template Library Samples