def cp04(L_x = 4, L_y = 4, n_x = 2, n_y = 4, n_steps = 100):

    cp = RhombusCreasePattern(n_steps = n_steps,
                              L_x = L_x,
                              L_y = L_y,
                              n_x = n_x,
                              n_y = n_y,
                              show_iter = False,
                              MAX_ITER = 500)

    n_h = cp.n_h
    n_i = cp.n_i
    n_v = cp.n_v

    z_nodes = n_h[(0, -1), :].flatten()
    z_cnstr = [[(n, 2, 1.0)] for n in z_nodes]

    y_links = []
    for n_arr in n_h.T:
        for n in n_arr[1:]:
            y_links.append([(n_arr[0], 1, 1.0), (n, 1, -1.0)])

    x_cnstr = [[(n_h[0, 0], 0, 1.0)]]

    y_cnstr = [[(n_h[0, -1], 1, 1.0)],
               [(n_h[0, 0], 1, 1.0)]]

    cp.cnstr_lhs = z_cnstr + y_links + x_cnstr + y_cnstr

    # lift node 0 in z-axes
    cp.cnstr_rhs = np.zeros((len(cp.cnstr_lhs),), dtype = float)
    cp.cnstr_rhs[-1] = 3.9

    return cp
def create_cp_fc_inclined(L_x=4, L_y=4, n_x=2, n_y=4, n_steps=100):
    """Create scalable rhombus crease pattern with face constraints
    """
    cp = RhombusCreasePattern(n_steps=n_steps, L_x=L_x, L_y=L_y, n_x=n_x, n_y=n_y, show_iter=False, MAX_ITER=50)

    n_h = cp.n_h
    n_v = cp.n_v
    n_i = cp.n_i

    y_links = []

    #    n_h0 = n_h[(0, -1), :-1]
    #    n_h1 = n_h[(0, -1), 1:]
    #    for nv, nh0, nh1 in zip(n_v.T, n_h0.T, n_h1.T):
    #        for v, h0, h1 in zip(nv, nh0, nh1):
    #            print 'constraining', h0, h1
    #            y_links.append([(h0, 1, 1.0), (h1, 1, -1.0)])

    n_h0 = n_h[(0, -1), :-1]
    n_h1 = n_h[(0, -1), 1:]
    for nv in n_v.T:
        print "adding constraint", nv
        y_links.append([(nv[0], 0, 1.0), (nv[1], 0, 1.0)])

    # here was a conflict @todo - resolve with Jan
    #    for nv, nh0, nh1 in zip(n_v.T, n_h0.T, n_h1.T):
    #        for v, h0, h1 in zip(nv, nh0, nh1):
    #            y_links.append([(v, 1, 1.0), (h1, 1, -0.5)])

    cp.cnstr_lhs = y_links
    cp.cnstr_rhs = np.zeros((len(cp.cnstr_lhs),), dtype=float)

    print "cnstr_lhs", cp.cnstr_lhs
    print "cnstr_rhs", cp.cnstr_rhs

    #    A = L_x * 0.2
    A = 0.2
    #    face_z_t = FF(Rf = z_ - 4 * A * t_ / L_x * x_ * (1 - x_ / L_x))
    face_z_t = FF(Rf=z_ - 4 * A * t_ * x_ * (1 - x_ / L_x))
    face_x_L2 = FF(Rf=x_ - L_x / 2)

    face_y_L2 = FF(Rf=y_ - L_y / 2)
    #    face_y_Ly = FF(Rf = y_ - L_y)

    # old
    n_h_idx = n_x / 2

    z_nodes = n_h[:, :].flatten()
    #    y_nodes = n_i[:, 0] # + list(n_v[:, :].flatten())
    y_nodes = n_i[0, 0]  # + list(n_v[:, :].flatten())

    cp.cnstr_lst = [
        (face_y_L2, [n_i[0, 0]]),
        (face_z_t, z_nodes),
        ##                    (face_x_L2, n_h[2, (0, -1)].flatten()),
        #                    (face_x_L2, n_h[n_h_idx, (0, -1)].flatten()),
        (face_x_L2, n_h[n_h_idx, :].flatten()),
    ]

    return cp
def cp01(L_x = 4, L_y = 2, n_x = 2, n_y = 2, n_steps = 80):

    cp = RhombusCreasePattern(n_steps = n_steps,
                              L_x = L_x,
                              L_y = L_y,
                              n_x = n_x,
                              n_y = n_y,
                              z0_ratio = 0.01,
                              show_iter = False,
                              MAX_ITER = 500)

    n_h = cp.n_h
    n_i = cp.n_i
    n_v = cp.n_v

    cp.cnstr_lhs = [[(n_h[0, 0], 2, 1.0)], # 0
                    [(n_h[0, -1], 2, 1.0)], # 1
                    [(n_h[-1, 0], 2, 1.0)], # 2
                    [(n_h[-1, -1], 2, 1.0)], # 3
                    [(n_h[1, 0], 2, 1.0)], # 4
                    [(n_h[0, 0], 1, 1.0), (n_h[1, 0], 1, -1.0)], # 5
                    [(n_h[0, 0], 1, 1.0), (n_h[-1, 0], 1, -1.0)], # 6
                    [(n_h[0, -1], 1, 1.0), (n_h[1, -1], 1, -1.0)], # 7
                    [(n_h[0, -1], 1, 1.0), (n_h[-1, -1], 1, -1.0)], # 8
                    [(n_h[1, 0], 0, 1.0)], # 9
                    [(n_h[0, -1], 1, 1.0)], # 10
                    ]

    # lift node 0 in z-axes
    cp.cnstr_rhs = np.zeros((14,), dtype = float)
    cp.cnstr_rhs[4] = 1.999999999

    return cp
def create_cp_fc(L_x = 4, L_y = 4, n_x = 1, n_y = 2,
         n_steps = 100):
    '''Create scalable rhombus crease pattern with face constraints
    '''
    cp = RhombusCreasePattern(n_steps = n_steps,
                              L_x = L_x,
                              L_y = L_y,
                              n_x = n_x,
                              n_y = n_y,
                              show_iter = False,
                              MAX_ITER = 500)

    n_h = cp.n_h
    n_i = cp.n_i
    n_v = cp.n_v
    n_h_idx = n_y / 4

    x_links = []
    y_links = []
    z_links = []

#    for n_arr in n_h[:, (-1,)].T:
#        for idx, n in enumerate(n_arr[1:]):
#            y_links.append([(n_arr[0], 1, 1.0), (n, 1, -1.0)])

    for n in n_v[-1, 1:]:
        x_links.append([(n_v[-1, 0], 0, 1.0), (n, 0, -1.0)])

    for n0, n1 in zip(n_v[0, :], n_v[-1, :]):
        z_links.append([(n0, 2, 1.0), (n1, 2, -1.0)])

    #cntrl = [[(n_h[-1, -1], 1, 1.0)]]
    #cntrl = [[(n_h[-1, 1], 0, 1.0)]]

    cp.cnstr_lhs = x_links + y_links + z_links # + cntrl
    #cp.cnstr_lhs = z_cnstr

    # lift node 0 in z-axes
    cp.cnstr_rhs = np.zeros((len(cp.cnstr_lhs),), dtype = float)
    #cp.cnstr_rhs[-1] = -L_x * 0.34

    face_z_0 = FF(Rf = z_ - 0)
    face_x_0 = FF(Rf = x_ - 0)
    face_x_L = FF(Rf = x_ - L_x * (1 - 0.2 * t_))
    face_y_0 = FF(Rf = y_ - 0)
    face_y_L = FF(Rf = y_ - L_y * (1 - 0.1 * t_))#* x_ / L_x))

    cp.cnstr_lst = [(face_x_0, n_h[0, :]), # [n_h[0, 0], n_h[0, -1]]),
                    (face_z_0, n_h[0, :]), # [n_h[0, 0], n_h[0, -1]]),
                    (face_y_0, n_h[:, 0]),
#                    (face_x_L, []),
                    (face_y_L, n_h[:, -1])]
#    cp.cnstr_rhs[-1] = -L_y * 0.9999

    return cp
def create_cp_fc_02(L_x=4, L_y=4, n_x=2, n_y=2, z0_ratio=0.1, n_steps=100):
    """Create scalable rhombus crease pattern with face constraints
       One basic element with general formulation (extension in y-direction variabel)
       (extension in x-direction has to be adepted manually)
    """
    cp = RhombusCreasePattern(
        n_steps=n_steps, L_x=L_x, L_y=L_y, n_x=n_x, n_y=n_y, show_iter=False, z0_ratio=z0_ratio, MAX_ITER=50
    )

    n_h = cp.n_h
    n_v = cp.n_v
    n_i = cp.n_i

    n_h_idx = n_x / 2
    n_h_idx = n_x / 2

    y_links = []
    for n_arr in n_h[0:3, :].T:
        for idx, n in enumerate(n_arr[1:]):
            n_x = len(n_arr)
            y_links.append([(n_arr[0], 1, 1.0), (n, 1, -1.0)])

    """
    Extension in x-direction
    """
    # y_links.append([(n_h[0,0], 1, 1.0), (n_h[-1,0], 1, -1.0)])
    # y_links.append([(n_h[0,0], 1, 1.0), (n_h[-2,0], 1, -1.0)])

    y_links.append([(n_h[0, -1], 1, 1.0)])
    y_links.append([(n_h[1, 0], 0, 1.0)])

    cp.cnstr_lhs = y_links

    print "n_h[1, 0]", n_h[1, 0]
    print "n_h[-1,-1]", n_h[-1, 0]
    print "n_h[1, -1]", n_h[1, -1]
    print "n_h[-1,-1]", n_h[-1, -1]

    cp.cnstr_rhs = np.zeros((len(cp.cnstr_lhs),), dtype=float)

    print "cnstr_lhs", cp.cnstr_lhs
    print "cnstr_rhs", cp.cnstr_rhs

    A = 0.2

    face_z_t = FF(Rf=z_ - 4 * A * t_ * x_ * (1 - x_ / L_x))

    cp.cnstr_lst = [(face_z_t, n_h[1:-1, 0]), (face_z_t, n_h[0, :]), (face_z_t, n_h[-1, :])]

    print "edge1", n_h[0, :]
    print "edge2", n_h[-1, :]
    print "center", n_h[1:-1, 0]
    return cp
def cp05(L_x = 4, L_y = 4, n_x = 2, n_y = 4,
         n_steps = 100, skew_coeff = 0.0):
    '''Exploit symmetric constraints
    '''
    cp = RhombusCreasePattern(n_steps = n_steps,
                              L_x = L_x,
                              L_y = L_y,
                              n_x = n_x,
                              n_y = n_y,
                              show_iter = False,
                              MAX_ITER = 500)

    n_h = cp.n_h
    n_i = cp.n_i
    n_v = cp.n_v

    z_nodes = n_h[(0, -1), :].flatten()
    z_cnstr = [[(n, 2, 1.0)] for n in z_nodes]

    y_links = []
    for n_arr in n_h[:, (0, -1)].T:
        for idx, n in enumerate(n_arr[1:]):
            n_x = len(n_arr)
            coeff = skew_coeff * float(idx + 1) / float(n_x)
            y_links.append([(n_arr[0], 1, 1.0 - coeff), (n, 1, -1.0)])

    for n_arr in n_h[:, 1:-1].T:
        y_links.append([(n_arr[0], 1, 1.0), (n_arr[-1], 1, -1.0)])

    x_links = []
    z_links = []
#    for n0, n1 in zip(n_h[1:-1, 0], n_h[1:-1, -1]):
#        x_links.append([(n0, 0, 1.0), (n1, 0, 1.0)])
#        z_links.append([(n0, 2, 1.0), (n1, 2, -1.0)])
    for n in n_v[0, 1:]:
        z_links.append([(n_v[0, 0], 2, 1.0), (n, 2, -1.0)])

    n_h_idx = n_y / 4
    x_cnstr = [[(n_h[0, n_h_idx], 0, 1.0)]]

    y_cnstr = [[(n_h[0, n_h_idx], 1, 1.0)]]

    cntrl = [[(n_h[-1, n_h_idx], 0, 1.0)]]
    #cntrl = [[(n_h[-1, 0], 1, 1.0)]]

    cp.cnstr_lhs = z_cnstr + x_links + y_links + z_links + x_cnstr + y_cnstr + cntrl

    # lift node 0 in z-axes
    cp.cnstr_rhs = np.zeros((len(cp.cnstr_lhs),), dtype = float)
    cp.cnstr_rhs[-1] = -L_x * 0.1

    return cp
def create_cp_fc_03(L_x=4, L_y=4, n_x=2, n_y=2, z0_ratio=0.1, n_steps=100):
    """Create scalable rhombus crease pattern with face constraints
       other constraints chosen (more in field in z-direction)
    """
    cp = RhombusCreasePattern(
        n_steps=n_steps, L_x=L_x, L_y=L_y, n_x=n_x, n_y=n_y, show_iter=False, z0_ratio=z0_ratio, MAX_ITER=50
    )

    n_h = cp.n_h
    n_v = cp.n_v
    n_i = cp.n_i

    y_links = []

    n_h_idx = (n_x + 1) / 2
    print "n_h_idx", n_h_idx

    for idx, n in enumerate(n_h[1:, 0]):
        y_links.append([(n_h[0, 0], 1, 1.0), (n, 1, -1.0)])

    for idx, n in enumerate(n_h[1:-1, -1]):
        y_links.append([(n_h[0, -1], 1, 1.0), (n, 1, -1.0)])

    for idx, n in enumerate(n_h[n_h_idx, 1:]):
        y_links.append([(n, 0, 1.0)])

    y_links.append([(n_h[0, -1], 1, 1.0)])

    cp.cnstr_lhs = y_links

    print "n_h[1, 0]", n_h[1, 0]
    print "n_h[-1,-1]", n_h[-1, 0]
    print "n_h[1, -1]", n_h[1, -1]
    print "n_h[-1,-1]", n_h[-1, -1]

    cp.cnstr_rhs = np.zeros((len(cp.cnstr_lhs),), dtype=float)

    print "cnstr_lhs", cp.cnstr_lhs
    print "cnstr_rhs", cp.cnstr_rhs

    A = 0.2
    face_z_t = FF(Rf=z_ - 4 * A * t_ * x_ * (1 - x_ / L_x))
    #    face_x_L2 = FF(Rf = x_ - L_x / 2)
    n_arr = np.hstack([n_h[n_h_idx, :].flatten(), n_h[0, :].flatten(), n_h[-1, :].flatten()])
    cp.cnstr_lst = [(face_z_t, n_arr)]

    print "edge1", n_h[0, :]
    print "edge2", n_h[-1, :]
    print "center", n_h[1:-1, :]
    return cp
def create_cp_fc_01(L_x=4, L_y=4, n_x=2, n_y=2, z0_ratio=0.1, n_steps=100):
    """Create scalable rhombus crease pattern with face constraints
       One basic element with no general formulation
    """
    cp = RhombusCreasePattern(
        n_steps=n_steps, L_x=L_x, L_y=L_y, n_x=n_x, n_y=n_y, show_iter=False, z0_ratio=z0_ratio, MAX_ITER=50
    )

    n_h = cp.n_h
    n_v = cp.n_v
    n_i = cp.n_i

    cp.cnstr_lhs = [
        [(n_h[0, 0], 1, 1.0), (n_h[1, 0], 1, -1.0)],  # 1
        [(n_h[0, 0], 1, 1.0), (n_h[-1, 0], 1, -1.0)],  # 2
        [(n_h[0, -1], 1, 1.0), (n_h[1, -1], 1, -1.0)],  # 3
        [(n_h[0, -1], 1, 1.0), (n_h[-1, -1], 1, -1.0)],  # 4
        [(n_h[0, -1], 1, 1.0)],
        [(n_h[1, 0], 0, 1.0)],
    ]

    print "n_h[1, 0]", n_h[1, 0]
    print "n_h[-1,-1]", n_h[-1, 0]
    print "n_h[1, -1]", n_h[1, -1]
    print "n_h[-1,-1]", n_h[-1, -1]

    cp.cnstr_rhs = np.zeros((len(cp.cnstr_lhs),), dtype=float)

    print "cnstr_lhs", cp.cnstr_lhs
    print "cnstr_rhs", cp.cnstr_rhs

    A = 0.2

    face_z_t = FF(Rf=z_ - 4 * A * t_ * x_ * (1 - x_ / L_x))
    face_x_L2 = FF(Rf=x_ - L_x / 2)

    cp.cnstr_lst = [(face_z_t, n_h[0, :]), (face_z_t, n_h[-1, :]), (face_z_t, [n_h[1, 0]])]

    print "edge1", n_h[0, :]
    print "edge2", n_h[-1, :]
    return cp
def cp03(L_x = 4, L_y = 4, n_x = 2, n_y = 4, n_steps = 80):

    cp = RhombusCreasePattern(n_steps = n_steps,
                              L_x = L_x,
                              L_y = L_y,
                              n_x = n_x,
                              n_y = n_y,
                              show_iter = False,
                              MAX_ITER = 500)

    n_h = cp.n_h
    n_i = cp.n_i
    n_v = cp.n_v

    cp.cnstr_lhs = [[(n_h[0, 0], 2, 1.0)], # 0
                    [(n_h[0, -1], 2, 1.0)], # 1
                    [(n_h[-1, 0], 2, 1.0)], # 2
                    [(n_h[-1, -1], 2, 1.0)], # 3
                    [(n_h[0, 1], 2, 1.0)], # 4
                    [(n_h[-1, 1], 2, 1.0)], # 5
                    [(n_h[0, 0], 1, 1.0)], # 6
                    [(n_h[0, 0], 1, 1.0), (n_h[1, 0], 1, -1.0)], # 7
                    [(n_h[0, 0], 1, 1.0), (n_h[-1, 0], 1, -1.0)], # 8
                    [(n_h[0, -1], 1, 1.0), (n_h[1, -1], 1, -1.0)], # 9
                    [(n_h[0, -1], 1, 1.0), (n_h[-1, -1], 1, -1.0)], # 10
                    [(n_h[1, 1], 0, 1.0)], # 11
                    [(n_h[0, -1], 1, 1.0)], # 12
                    [(n_h[1, 1], 1, 1.0), (n_h[0, 1], 1, -1.0)], # 13
                    [(n_h[1, 1], 1, 1.0), (n_h[-1, 1], 1, -1.0)], # 14
#                    [(n_h[1, 1], 2, 1.0), (n_h[1, 0], 2, -1.0)], # 13
#                    [(n_h[1, 1], 1, 1.0), (n_h[1, -1], 2, -1.0)], # 14
                    ]

    # lift node 0 in z-axes
    cp.cnstr_rhs = np.zeros((15,), dtype = float)
    cp.cnstr_rhs[6] = 3.95

    return cp
def create_cp_dc(L_x = 4, L_y = 4, n_x = 1, n_y = 2,
         n_steps = 100):
    '''Create scalable rhombus crease pattern with dof_constraints
    '''
    cp = RhombusCreasePattern(n_steps = n_steps,
                              L_x = L_x,
                              L_y = L_y,
                              n_x = n_x,
                              n_y = n_y,
                              show_iter = False,
                              MAX_ITER = 500)

    n_h = cp.n_h
    n_i = cp.n_i
    n_v = cp.n_v
    n_h_idx = n_y / 4

    x_links = []
    y_links = []
    z_links = []

    z_nodes = n_h[(0, 0, -1, -1), (0, -1, -1, 0)].flatten()
    print 'z_nodes', z_nodes

    #z_cnstr = [[(n, 2, 1.0)] for n in z_nodes]
    x_cnstr = [[(n_h[0, 0], 0, 1.0)]]
    y_cnstr = [[(n_h[0, 0], 1, 1.0)]]
    z_cnstr = [[(n_h[0, 0], 2, 1.0)]]

    for n_arr in n_h[:, (0, -1)].T:
        for idx, n in enumerate(n_arr[1:]):
            n_x = len(n_arr)
            y_links.append([(n_arr[0], 1, 1.0), (n, 1, -1.0)])

    for n in n_h[0, 1:]:
        z_links.append([(n_h[0, 0], 2, 1.0), (n, 2, -1.0)])
        x_links.append([(n_h[0, 0], 0, 1.0), (n, 0, -1.0)])
    #x_links.append([(n_h[0, -1], 0, 1.0), (n_h[0, -1], 1, -0.5)])

    for n in n_v[-1, 1:]:
        x_links.append([(n_v[-1, 0], 0, 1.0), (n, 0, -1.0)])

    for n0, n1 in zip(n_v[0, :], n_v[-1, :]):
        z_links.append([(n0, 2, 1.0), (n1, 2, -1.0)])

    #cntrl = [[(n_h[-1, -1], 1, 1.0)]]
    cntrl = [[(n_h[-1, 1], 0, 1.0)]]

    print 'x_cnstr', len(x_cnstr)
    print 'y_cnstr', len(y_cnstr)
    print 'z_cnstr', len(z_cnstr)
    print 'x_links', len(x_links)
    print 'y_links', len(y_links)
    print 'z_links', len(z_links)

    cp.cnstr_lhs = z_cnstr + x_links + y_links + z_links + x_cnstr + y_cnstr + cntrl
    #cp.cnstr_lhs = z_cnstr

    # lift node 0 in z-axes
    cp.cnstr_rhs = np.zeros((len(cp.cnstr_lhs),), dtype = float)
    cp.cnstr_rhs[-1] = -L_x * 0.34

#    cp.cnstr_rhs[-1] = -L_y * 0.9999

    return cp
def create_cp_fc_inclined(L_x = 4, L_y = 4, n_x = 1, n_y = 2,
         n_steps = 100):
    '''Create scalable rhombus crease pattern with face constraints
    '''
    cp = RhombusCreasePattern(n_steps = n_steps,
                              L_x = L_x,
                              L_y = L_y,
                              n_x = n_x,
                              n_y = n_y,
                              show_iter = False,
                              MAX_ITER = 2000)

    n_h = cp.n_h
    n_i = cp.n_i
    n_v = cp.n_v
    n_h_idx = n_y / 4

    x_links = []
    y_links = []
    z_links = []

#    for n_arr in n_h[:, (-1,)].T:
#        for idx, n in enumerate(n_arr[1:]):
#            y_links.append([(n_arr[0], 1, 1.0), (n, 1, -1.0)])

#    for n in n_v[-1, 1:]:
#        x_links.append([(n_v[-1, 0], 0, 1.0), (n, 0, -1.0)])

#    for n0, n1 in zip(n_v[0, :], n_v[-1, :]):
#        z_links.append([(n0, 2, 1.0), (n1, 2, -1.0)])
#        y_links.append([(n0, 1, 1.0), (n1, 1, -1.0)])

    #cntrl = [[(n_h[-1, -1], 1, 1.0)]]
    #cntrl = [[(n_h[-1, 1], 0, 1.0)]]

    cp.cnstr_lhs = x_links + y_links + z_links # + cntrl
    #cp.cnstr_lhs = z_cnstr

    # lift node 0 in z-axes
    cp.cnstr_rhs = np.zeros((len(cp.cnstr_lhs),), dtype = float)
    #cp.cnstr_rhs[-1] = -L_x * 0.34

#    face_z_0 = FF(Rf = z_ - (1 - x_ / L_x) * 0.2 * t_)
    face_z_0 = FF(Rf = z_ - 0)
    face_x_0 = FF(Rf = x_ - 0)
#    face_x_L = FF(Rf = x_ - L_x * (1 - 0.2 * t_))
#    face_y_0 = FF(Rf = y_ - 0)
#    face_y_L = FF(Rf = y_ - L_y * (1 - 0.1 * t_))
#parallel movement bothsided
    face_y_0 = FF(Rf = y_ - L_y * (0.05 * t_))# * x_ / L_x)
    face_y_L = FF(Rf = y_ - L_y * (1 - 0.05 * t_))# * x_ / L_x)

#parallel movement: one side inclined
#    face_y_0 = FF(Rf = y_ - L_y / 2.0 * (0.1 * t_) * x_ / L_x)
#    face_y_L = FF(Rf = y_ - L_y * (1 - 0.05 * t_))# * x_ / L_x)

#one side inclined, other side fixed
#    face_y_0 = FF(Rf = y_ - 0)
#    face_y_L = FF(Rf = y_ - L_y  + L_y * 0.1 * t_* x_ / L_x)

##symmetric inclined along x
#    face_y_0 = FF(Rf = y_ - L_y / 2.0 * 0.1 * t_ * x_ / L_x)
#    face_y_L = FF(Rf = y_ - L_y + L_y / 2.0 * 0.1 * t_ * x_ / L_x)
#
##symmetric inclined along both x and y
#    face_y_0 = FF(Rf = y_ - L_y / 2.0 * 0.05 * t_ * y_ / L_y)
#    face_y_L = FF(Rf = y_ - L_y + L_y / 2.0 * 0.05 * t_ * y_ / L_y)

#    cp.cnstr_lst = [(face_x_0, n_h[0, :]),
#                    (face_z_0, n_h[0, :]),
#                    (face_y_0, n_h[:, 0]),
#                    (face_y_L, n_h[:, -1])]

    z_nodes = n_h[:, :].flatten()
    print z_nodes
    cp.cnstr_lst = [(face_x_0, [n_h[0, 0]]),
                    (face_z_0, z_nodes),
                    (face_y_0, n_h[:, 0]),
                    (face_y_L, n_h[:, -1])]

    return cp