Dot and Cross Product

Write a function to evaluate the cross product and dot product of two vectors V₁ and V₂ , where

 V₁ = V_1xi + V_1yj + V_1zk  and  V₂ = V_2xi + V_2yj + V_2zk .

 Note that this function returns a real array as its result .

Use this function to calculate the cross product and dot product of  V₁=[-2 , 4 , 0.5]  and V₂=[0.5 , 3 , 2] .

Program Dot_and_Cross_Product

    implicit none

    Integer :: i

    real :: a(3) , b(3) , dot , crossX , crossY , crossZ

    read(*,*) (a(i),i=1,3)

    read(*,*) (b(i),i=1,3)

    write(*,11) 'Dot Product =' , dot(a,b)

    11 format (A13 , F8.3)

    Write(*,12) 'Cross Product=' , crossX(a,b) , crossY(a,b) , crossZ(a,b)

    12 format ( A14 , f5.2 , 'i+' , f5.2 , 'j' , f5.2, 'k')

    end program

real function dot (a,b)

implicit none

real :: a(3) , b(3)

dot = a(1)*b(1)+a(2)*b(2)+a(3)*b(3)

end function

real function crossX(a,b)

implicit none

real :: a(3) , b(3)

Crossx = b(3)*a(2)-b(2)*a(3)

end function

real function crossY(a,b)

implicit none

real :: a(3) , b(3)

CrossY = b(1)*a(3)-a(1)*b(3)

end function

real function crossZ(a,b)

implicit none

real :: a(3) , b(3)

CrossZ = a(1)*b(2)-a(2)*b(1) 

end function