def fort_read(self,fmt,dtype=None):
"""Read a Fortran binary record.
Inputs:
fmt -- If dtype is not given this represents a struct.pack
format string to interpret the next record. Otherwise this
argument is ignored.
dtype -- If dtype is not None, then read in the next record as
an array of type dtype.
Outputs: (data,)
data -- If dtype is None, then data is a tuple containing the output
of struct.unpack on the next Fortan record.
If dtype is a datatype string, then the next record is
read in as a 1-D array of type datatype.
"""
lookup_dict = {'ieee-le':"<",'ieee-be':">",'native':''}
if dtype is None:
fmt = lookup_dict[self.format] + fmt
numbytes = struct.calcsize(fmt)
nn = struct.calcsize("i");
if (self.raw_read(nn) == ''):
raise ValueError, "Unexpected end of file..."
strdata = self.raw_read(numbytes)
if strdata == '':
raise ValueError, "Unexpected end of file..."
data = struct.unpack(fmt,strdata)
if (self.raw_read(nn) == ''):
raise ValueError, "Unexpected end of file..."
return data
else: # Ignore format string and read in next record as an array.
fmt = lookup_dict[self.format] + "i"
nn = struct.calcsize(fmt)
nbytestr = self.raw_read(nn)
if nbytestr == '':
raise ValueError, "Unexpected end of file..."
nbytes = struct.unpack(fmt,nbytestr)[0]
howmany, dtype = getsize_type(dtype)
ncount = nbytes / howmany
if ncount*howmany != nbytes:
self.rewind(4)
raise ValueError, "A mismatch between the type requested and the data stored."
if ncount < 0:
raise ValueError, "Negative number of bytes to read:\n file is probably not opened with correct endian-ness."
if ncount == 0:
raise ValueError, "End of file? Zero-bytes to read."
retval = numpyio.fread(self.file, ncount, dtype, dtype, self.bs)
if len(retval) == 1:
retval = retval[0]
if (self.raw_read(nn) == ''):
raise ValueError, "Unexpected end of file..."
return retval
def fort_read(self, fmt, dtype=None):
"""Read a Fortran binary record.
Inputs:
fmt -- If dtype is not given this represents a struct.pack
format string to interpret the next record. Otherwise this
argument is ignored.
dtype -- If dtype is not None, then read in the next record as
an array of type dtype.
Outputs: (data,)
data -- If dtype is None, then data is a tuple containing the output
of struct.unpack on the next Fortan record.
If dtype is a datatype string, then the next record is
read in as a 1-D array of type datatype.
"""
lookup_dict = {'ieee-le': "<", 'ieee-be': ">", 'native': ''}
if dtype is None:
fmt = lookup_dict[self.format] + fmt
numbytes = struct.calcsize(fmt)
nn = struct.calcsize("i")
if (self.raw_read(nn) == ''):
raise ValueError, "Unexpected end of file..."
strdata = self.raw_read(numbytes)
if strdata == '':
raise ValueError, "Unexpected end of file..."
data = struct.unpack(fmt, strdata)
if (self.raw_read(nn) == ''):
raise ValueError, "Unexpected end of file..."
return data
else: # Ignore format string and read in next record as an array.
fmt = lookup_dict[self.format] + "i"
nn = struct.calcsize(fmt)
nbytestr = self.raw_read(nn)
if nbytestr == '':
raise ValueError, "Unexpected end of file..."
nbytes = struct.unpack(fmt, nbytestr)[0]
howmany, dtype = getsize_type(dtype)
ncount = nbytes / howmany
if ncount * howmany != nbytes:
self.rewind(4)
raise ValueError, "A mismatch between the type requested and the data stored."
if ncount < 0:
raise ValueError, "Negative number of bytes to read:\n file is probably not opened with correct endian-ness."
if ncount == 0:
raise ValueError, "End of file? Zero-bytes to read."
retval = numpyio.fread(self.file, ncount, dtype, dtype, self.bs)
if len(retval) == 1:
retval = retval[0]
if (self.raw_read(nn) == ''):
raise ValueError, "Unexpected end of file..."
return retval
def read(self,count,stype,rtype=None,bs=None,c_is_b=0):
"""Read data from file and return it in a numpy array.
Inputs:
count -- an integer specifying the number of elements of type
stype to read or a tuple indicating the shape of
the output array.
stype -- The data type of the stored data (see fwrite method).
rtype -- The type of the output array. Same as stype if None.
bs -- Whether or not to byteswap (or use self.bs if None)
c_is_b --- If non-zero then the count is an integer
specifying the total number of bytes to read
(must be a multiple of the size of stype).
Outputs: (output,)
output -- a numpy array of type rtype.
"""
if bs is None:
bs = self.bs
else:
bs = (bs == 1)
howmany,stype = getsize_type(stype)
shape = None
if c_is_b:
if count % howmany != 0:
raise ValueError, "When c_is_b is non-zero then " \
"count is bytes\nand must be multiple of basic size."
count = count / howmany
elif type(count) in [types.TupleType, types.ListType]:
shape = list(count)
# allow -1 to specify unknown dimension size as in reshape
minus_ones = shape.count(-1)
if minus_ones == 0:
count = product(shape,axis=0)
elif minus_ones == 1:
now = self.tell()
self.seek(0,2)
end = self.tell()
self.seek(now)
remaining_bytes = end - now
know_dimensions_size = -product(count,axis=0) * getsize_type(stype)[0]
unknown_dimension_size, illegal = divmod(remaining_bytes,
know_dimensions_size)
if illegal:
raise ValueError("unknown dimension doesn't match filesize")
shape[shape.index(-1)] = unknown_dimension_size
count = product(shape,axis=0)
else:
raise ValueError(
"illegal count; can only specify one unknown dimension")
shape = tuple(shape)
if rtype is None:
rtype = stype
else:
howmany,rtype = getsize_type(rtype)
if count == 0:
return zeros(0,rtype)
retval = numpyio.fread(self.file, count, stype, rtype, bs)
if shape is not None:
retval = resize(retval, shape)
return retval
from numpyio import fread, fwrite
from sys import argv
print "\nReading info from %s.hdr and" % argv[1]
print "%s.dat\n" % argv[1]
print "Writing %s.raw\n" % argv[1]
HEADERLEN = 640
BLOCKLEN = 49152
# Read the header file
file = open(argv[1]+'.hdr', 'r')
data = fread(file, HEADERLEN+8, 'b')
file.close()
header = data[4:-4]
infile = open(argv[1]+'.dat', 'r')
outfile = open(argv[1]+'.raw', 'w')
# Read and write the raw data
while (1):
data = fread(infile, BLOCKLEN+8, 'b')
if (len(data)==BLOCKLEN+8):
fwrite(outfile, HEADERLEN, header, 'b')
fwrite(outfile, BLOCKLEN, data[4:-4], 'b')
else:
break
print ''
infile.close()
outfile.close()
from __future__ import print_function
from numpyio import fread, fwrite
from sys import argv
print("\nReading info from %s.hdr and" % argv[1])
print("%s.dat\n" % argv[1])
print("Writing %s.raw\n" % argv[1])
HEADERLEN = 640
BLOCKLEN = 49152
# Read the header file
file = open(argv[1] + '.hdr', 'r')
data = fread(file, HEADERLEN + 8, 'b')
file.close()
header = data[4:-4]
infile = open(argv[1] + '.dat', 'r')
outfile = open(argv[1] + '.raw', 'w')
# Read and write the raw data
while (1):
data = fread(infile, BLOCKLEN + 8, 'b')
if (len(data) == BLOCKLEN + 8):
fwrite(outfile, HEADERLEN, header, 'b')
fwrite(outfile, BLOCKLEN, data[4:-4], 'b')
else:
break
print('')
infile.close()
def read(self, count, stype, rtype=None, bs=None, c_is_b=0):
"""Read data from file and return it in a numpy array.
Inputs:
count -- an integer specifying the number of elements of type
stype to read or a tuple indicating the shape of
the output array.
stype -- The data type of the stored data (see fwrite method).
rtype -- The type of the output array. Same as stype if None.
bs -- Whether or not to byteswap (or use self.bs if None)
c_is_b --- If non-zero then the count is an integer
specifying the total number of bytes to read
(must be a multiple of the size of stype).
Outputs: (output,)
output -- a numpy array of type rtype.
"""
if bs is None:
bs = self.bs
else:
bs = (bs == 1)
howmany, stype = getsize_type(stype)
shape = None
if c_is_b:
if count % howmany != 0:
raise ValueError, "When c_is_b is non-zero then " \
"count is bytes\nand must be multiple of basic size."
count = count / howmany
elif type(count) in [types.TupleType, types.ListType]:
shape = list(count)
# allow -1 to specify unknown dimension size as in reshape
minus_ones = shape.count(-1)
if minus_ones == 0:
count = product(shape, axis=0)
elif minus_ones == 1:
now = self.tell()
self.seek(0, 2)
end = self.tell()
self.seek(now)
remaining_bytes = end - now
know_dimensions_size = -product(
count, axis=0) * getsize_type(stype)[0]
unknown_dimension_size, illegal = divmod(
remaining_bytes, know_dimensions_size)
if illegal:
raise ValueError(
"unknown dimension doesn't match filesize")
shape[shape.index(-1)] = unknown_dimension_size
count = product(shape, axis=0)
else:
raise ValueError(
"illegal count; can only specify one unknown dimension")
shape = tuple(shape)
if rtype is None:
rtype = stype
else:
howmany, rtype = getsize_type(rtype)
if count == 0:
return zeros(0, rtype)
retval = numpyio.fread(self.file, count, stype, rtype, bs)
if shape is not None:
retval = resize(retval, shape)
return retval
