variable in python..

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# This example computes the diffraction from a superhydrophobic optical grating
# immersed in water. A curved liquid-gas interface spans each groove.


from mrcwa import *
from tables import *

# dimensionless curvature of the interface


#Variable
M1=0
M2=0
M3=0

# groove width
g = 5.0
# wall width
w = 3.0
# depth
h = 6
# period
T = g + w
r = 0.5 * g
#Materials definition
air = material(1.0)
water = material(1.33,'blue')
Si = material((4.367+0.079j),'black')
output_file = open("SuperHydro_varying_kr","w")

For kr in range(1, 5)

    R=r/kr
    l = R * sqrt( 1 - r**2 / R**2 )
    zeta = R * ( 1 - sqrt( 1 - r**2 / R**2 ) )

    if kr < 0:

        box + halfspace(-inf, 0.0, Si)
        box + rectangle(g, h, air, (0, -0.5*h) )
        box + circle(R, water, (.0,-l))

        ymesh = hstack( ( array([0.0,r]), arange(r+h+zeta-d, h+r+d, d), array([h+g]) ) )
         print 'good'
    elif kr > 0:

        box + circle(R, air, (.0,-l))
        box + halfspace(-inf, 0.0, Si)
        box + rectangle(g, h, air, (0, -0.5*h) )

        ymesh = hstack( ( array([0.0,r]), arange(r+h-d, h+g+d, d) ) )

    xmesh = hstack( (arange(0,g+0.01,0.001), array([T]) ) )
    grating=stack( box.slice(xmesh=xmesh, ymesh=ymesh) )
     print 'bad'
    M1=0
    M2=0
    M3=0
    M =-50
    P = 50

    grating.order=(M,P+1)

    grating.l = 0.488

    grating.fourier()

    angles = arange(30,87,1)
    orders = arange(M,P+1)


    for i,theta in enumerate(angles):
        grating.theta = theta
        grating.wavevec()
        grating.partialr()
        L=grating.partialr()[49]*grating.partialr()[49]
        Q=grating.partialr()[50]*grating.partialr()[50]
        S=grating.partialr()[51]*grating.partialr()[51]
        M1+=L
        M2+=Q
        M3+=S
    output_file.write(" %s  %s  %s  %s \n" % (kr, M1, M2, M3) )
output_file.close()