pyyeti.nastran.op4.OP4

class pyyeti.nastran.op4.OP4

Class for reading/writing Nastran output4 (.op4) files.

See demo below and refer to the help on these functions for more information: write() (or save()), load() (or the lower level dctload(), listload()), and dir(). save is an alias for write.

Examples

Instantiate the class and create matrices for demo:

>>> from pyyeti.nastran import op4
>>> o4 = op4.OP4()
>>> import numpy as np
>>> rng = np.random.default_rng()
>>> r = rng.normal(size=(3, 5))
>>> c = r + 1j*rng.normal(size=(3, 5))

Write binary op4 file, with ‘r’ first:

>>> o4.write('testbin.op4', ['r', 'c'], [r, c])

Write ascii op4 file without caring about order:

>>> o4.write('testascii.op4', dict(r=r, c=c), binary=False)

To read an op4 file into a dictionary (indexed by the name in lower case):

>>> dct = o4.load('testbin.op4', into='dct')

Note: to preserve order, the dictionary returned by “load” or “read” is actually an OrderedDict from the standard Python “collections” module (collections.OrderedDict).

To read into a list:

>>> names, mats, forms, mtypes = o4.load('testascii.op4',
...                                      into='list')

Check some results:

>>> print(np.all(r == dct['r'][0]))
True

>>> if names[0] == 'c':
...     print(np.all(c == mats[0]))
... else:
...     print(np.all(c == mats[1]))
True

To print a ‘directory’ of an op4 file:

>>> d = o4.dir('testbin.op4')
r       ,      3 x 5     , form=2, mtype=2
c       ,      3 x 5     , form=2, mtype=4

Clean up:

>>> import os
>>> os.remove('testbin.op4')
>>> os.remove('testascii.op4')

__init__()

Methods

__init__()
dctload(filename[, namelist, justmatrix, sparse])	Read all matching matrices from op4 file into dictionary.
dir(filename[, verbose])	Directory of all matrices in op4 file.
listload(filename[, namelist, sparse])	Read all matching matrices from op4 file into a list; useful if op4 file has duplicate names.
load(filename[, namelist, into, justmatrix, ...])	Read all matching matrices from op4 file into dictionary or list; interface to dctload() and listload().
write(filename, names[, matrices, binary, ...])	Write op4 file.