###############################################################################
# Usage: python plaintext.py files
#
# Purpose:
#   This program takes a set of plaintext files on the command line and glues
#   them together into a BOV file that can be plotted using VisIt.
#
# Notes:      The input files must be plain text and contain only columns
#             of numbers. All input files must have the same number of rows and
#             columns.
#
# Programmer: Brad Whitlock
# Date:       Fri Feb  3 16:12:53 PST 2012
#
# Modifications:
#
###############################################################################
import sys, string, struct
 
# Read one input file and return its data as a list.
def readslice(filename):
    f = open(filename, "rt")
    lines = f.readlines()
    f.close()
 
    data = []
    nrows = 0
    for line in lines:
        toks = string.split(line, " ")
        vals = []
        for t in toks:
            try:
                v = float(t)
                vals = vals + [v]
            except:
                pass
        if nrows == 0:
            ncols = len(vals)
        for v in vals:
            data = data + [v]
        nrows = nrows + 1
    print data
    return data,ncols,nrows
 
# Insert the data from one slice into the overall 3D array.
def insertslice(data, slice, k, nx, ny):
    index2 = 0
    for j in xrange(ny):
        for i in xrange(nx):
            # Note the reversal in j here to make the data look the same 
            # as the input text file.
            index3 = k * nx*ny + (ny-1-j)*nx + i
            data[index3] = slice[index2]
            index2 = index2 + 1
 
# Write the 3D array out to a BOV file.
def saveBOV(filename, data, varname, nx, ny, nz):
    f = open(filename + ".dat", "wb")
    for d in data:
        f.write(struct.pack('f', d))
    f.close()
 
    f = open(filename + ".bov", "wt")
    f.write("TIME: 0\n")
    f.write("DATA_FILE: %s.dat\n" % filename)
    f.write("DATA_SIZE: %d %d %d\n" % (nx,ny,nz))
    f.write("DATA_FORMAT: FLOAT\n")
    f.write("VARIABLE: %s\n" % varname)
    f.write("DATA_ENDIAN: LITTLE\n")
    f.write("CENTERING: zonal\n")
    f.close()
 
# Create some test data.
def write_test_data():
    NX,NY,NZ = 3,4,5
    idx = 0
    for k in xrange(NZ):
        filename = "input%02d.txt" % k
        f = open(filename, "wt")
        for j in xrange(NY):
            line = ""
            for i in xrange(NX):
                line = line + "%d " % idx
                idx = idx + 1
            f.write("%s\n" % line)
        f.close()
 
# Iterate over the filenames that were passed on the command line and
# glue them together into BOV.
def main():
    nx = 0
    ny = 0
    nz = len(sys.argv[1:])
    data = []
 
    k = 0
    for filename in sys.argv[1:]:
        slice,dimx,dimy = readslice(filename)
        if k == 0:
            nx,ny = dimx,dimy
            data = [0] * (nx * ny * nz)
        insertslice(data, slice, k, nx, ny)
        k = k + 1
    print data
    saveBOV("output", data, "var", nx, ny, nz)
 
# Call it.
#write_test_data()
main()

Category: Reading/Writing Data