convert a cell centered tecplot block ascii data to a VTK RECTILINEAR_GRID format data

cell2vtk.py

from numpy import *

#filename = "data.txt"
datadir = "Tr0.8_Kn0.1/GH_16_16_16/"
filename = datadir+"creep3d.dat"

NX = 40
NZ = 40
NY = 80

NX1 = NX + 1
NY1 = NY + 1
NZ1 = NZ + 1

datanames = ["X", "Y", "Z", "Rho", "U", "V", "W", "T", "Qx", "Qy", "Qz"]

data = []

num_data = len(datanames)

num_eles = zeros(num_data)
num_eles[:3] = NX1*NY1*NZ1
num_eles[3:] = NX*NY*NZ

for i in range(num_data):
    data.append(zeros(num_eles[i]))
    
count_eles = zeros(num_data)


di = -1
with open(filename) as f:
    next(f)
    next(f)
    # skip two lines
    # each variable array start with blank line
    for line in f:
        if line not in ['\n', '\r\n']:
            numbers_float = map(float, line.split())
            num_f = len(numbers_float)
            data[di][count_eles[di]:count_eles[di]+num_f] = array(numbers_float)
            count_eles[di] += num_f
        else:
            di = di + 1


# vtk DataFile Version 3.0

with open(datadir+"cell.vtk", "w") as f:
    f.write("# vtk DataFile Version 3.0\n")
    f.write("vtk output\n")
    f.write("ASCII\n")
    f.write("DATASET RECTILINEAR_GRID\n")
    f.write("DIMENSIONS   %d   %d    %d\n"%(NX1, NY1, NZ1))
    f.write("X_COORDINATES   %d float\n"%(NX1))
    for i in range(NX1):
        f.write("%.18e\n"%data[0][i])
    f.write("Y_COORDINATES   %d float\n"%(NY1))
    for i in range(NY1):
        f.write("%.18e\n"%data[1][i*NX1])
    f.write("Z_COORDINATES   %d float\n"%(NZ1))
    for i in range(NZ1):
        f.write("%.18e\n"%data[2][i*NX1*NY1])

    f.write("CELL_DATA %d\n"%(NX*NY*NZ))
    f.write("SCALARS rho float 1\n")
    f.write("LOOKUP_TABLE default")
    for i in range(NX*NY*NZ):
        f.write("\n%.18e"%data[3][i])

    f.write("SCALARS T float 1\n")
    f.write("LOOKUP_TABLE default")
    for i in range(NX*NY*NZ):
        f.write("\n%.18e"%data[7][i])

    f.write("\nVECTORS U float")
    for i in range(NX*NY*NZ):
        f.write("\n%.18e %.18e %.18e"%(data[4][i], data[5][i], data[6][i]))

    f.write("\nVECTORS Q float")
    for i in range(NX*NY*NZ):
        f.write("\n%.18e %.18e %.18e"%(data[8][i], data[9][i], data[10][i]))

PS: data block entries are separated by a blank line
PS: Data header in creep3d.dat is

VARIABLES = X, Y, Z, RHO, U, V, W, T, Qx, Qy, Qz
ZONE I = 41 J = 81 K = 41 DATAPACKING=BLOCK, VARLOCATION=([4,5,6,7,8,9,10,11]=CELLCENTERED)