## Tuesday, 13 March 2012

### The sinh Function in C & C++

More functions from the  <math.h> or <cmath> header files. Today it’s about the sinh function.

The sinh function returns the hyperbolic sine for any real number and is defined as shown below.

From C11 standard.

The newest standard includes the asinh function, but it is not implemented in Visual C++ 2010; however, you can use the log function to determine the arc hyperbolic sine.

Test Code.

I tested the functions in Visual C++ 2010 as an console application.

// The standard library includes the system function.
#include <cstdlib>

// C++ standard I/O library.
#include <cstdio>

// C++ math library.
#include <cmath>

int main()
{
// Header.
printf("The sinh Function in C & C++\n\n");
printf("Given x, any real number, the function returns y \n");
printf("equal to the hyperbolic sine of x.\n\n");

// Counter for loop.
int i;
// Argument.
double x;
// Result.
double y, y2;

printf("    x   =>  sinh(x) =  0.5 * (exp(x) - 1.0/exp(x)) \n\n");
for (i = -5; i <= 5; ++i)
{
x = i * 1.0;
y = sinh(x);
y2 = 0.5 * (exp(x) - 1.0/exp(x));
printf ("%6.1f  => %8.4f = %8.4f\n", x, y, y2);
}
// Keep console window open.
system("pause");

// Return some value.
return 0;
} // end main

Output.