main/src/georegression/geometry/UtilVector2D_F64.java
public static double acute( Vector2D_F64 a , Vector2D_F64 b ) {
		double dot = a.dot(b);

		double value = dot/(a.norm()*b.norm());
		if( value > 1.0 )
			value = 1.0;
		else if( value < -1.0 )
			value = -1.0;

		return Math.acos( value );
	}
public static double acute( Vector2D_F64 a , Vector2D_F64 b ) {
		double dot = a.dot(b);

		double value = dot/(a.norm()*b.norm());
		if( value > 1.0 )
			value = 1.0;
		else if( value < -1.0 )
			value = -1.0;

		return Math.acos( value );
	}
public static double acute ( Vector2D_F64 a , Vector2D_F64 b ) { double dot = a . dot ( b ) ; double value = dot / ( a . norm ( ) * b . norm ( ) ) ; if ( value > 1.0 ) value = 1.0 ; else if ( value < - 1.0 ) value = - 1.0 ; return Math . acos ( value ) ; }
Returns the acute angle between the two vectors.  Computed using the dot product.
@param a vector
@param b vector
@return acute angle
Returns the acute angle between the two vectors . Computed using the dot product .