genVectorNegate
in genMath.lib

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Sample Code

int genVectorNegate(
                                        float *VectorA,       // pointer to array holding vector A
                                        float *VectorB,       // pointer to array for vector B
                                        int dimen)                // dimension of vectors A and B

This function computes the negative of a vector of dimension n:

b(i)  =  -a(i) 

The explicit routines VectorNegate2d and VectorNegate3d are faster due to code
optimizations in the explicit algorithms.

The return code is errno, defined in the C standard library (math.h).  This is an integer value
for math errors.

Sample Application:
/////////// splgnVNg.c for genVectorNegate Library Function //////////
//								    //																//
//	For this sample, 3-d vectors are used.  The vector is	    //
//	stored in array a and the negative is returned in array b.  //
//								    //
//////////////////////////////////////////////////////////////////////
//////////////////////////// INCLUDES ////////////////////////////////

#include "stdio.h"
#include "genMath.h"

////////////////////////////// MAIN //////////////////////////////////
void main()
{

	//local declarations
	//integers
	int i; 			// dimension counter
	int retcode; 		// return code for call to genVectorNegate

	//floats
	float a[3]; 		// vector A
	float b[3]; 		// vector B

	//character strings
	char ch; 		//input string to exit

	//intialize the A vectors
	a[0] = (float)1.234;
	a[1] = (float)-.678;
	a[2] = (float)10.3;

	//negate the vector
	retcode = genVectorNegate(a,b,3);

	//display the result

	printf("%s", "Resultant Components: \n\n");

	for(i=0;i<=2;++i){

		printf("%s%d%s%f%s", "b[",i,"] = ", b[i],"\n");

	}

	printf("%s","\n");

	//display closing message and wait for <enter> before exiting
	printf("Press <Enter> to end");
	scanf("%c", &ch);

} // End Main
//////////////////////// End splgnVNg.c ///////////////////////
The reader may verify that the vector (array) a is negated.
Output from the test program splgnVNg.c: 
Resultant Components:
b[0] = -1.234000
b[1] = 0.678000
b[3] = -10.300000