utils Package

This is the pyNastran.utils.rst file.

#:mod:gui_io Module #——————– # #.. inheritance-diagram:: pyNastran.utils.gui_io # #.. automodule:: pyNastran.utils.gui_io # :members: # :undoc-members: # :show-inheritance:

mathematics Module

Various mathematical functions are defined in this file. This includes:
  • gauss(n)

  • get_abs_index(data, axis=1)

  • get_abs_max(min_values, max_values)

  • get_max_index(data, axis=1)

  • get_min_index(data, axis=1)

  • integrate_positive_unit_line(x, y, min_value=0.)

  • integrate_unit_line(x, y)

  • is_float_ranged(a, x, b)

  • is_list_ranged(a, List, b)

  • list_print(list_a, tol=1e-8, float_fmt=’%-3.2g’, zero_fmt=’ 0’)

  • print_annotated_matrix(A, row_names=None, col_names=None, tol=1e-8)

  • print_matrix(A, tol=1e-8)

  • reduce_matrix(matrix_a, nids)

  • roundup(value, round_increment=100)

  • solve_tridag(A, D)

  • unique2d(a)

All beams are LineProperty objects. Multi-segment beams are IntegratedLineProperty objects.

pyNastran.utils.mathematics.Area(a, b)
pyNastran.utils.mathematics.gauss(n)[source]

A quadrature rule: an approximation of the definite integral of a function. Currently implementation supports up to 5 quadrature points.

Function returns following values depending on n (number of points):

  • n = 1:

  • f$ 0 f$ –> f$ 2 f$

  • n = 2:

  • f$ pm 1/sqrt{3} f$ –> f$ 1 f$

  • n = 3

  • f$ 0 f$ –> f$ 8/9 f$

  • f$ pmsqrt{3/5} f$ –> f$ 5/9 f$

  • n = 4:

  • f$ pmsqrt{left( 3 - 2sqrt{6/5} right)/7} f$ –> f$ (18+sqrt{30})/36 f$

  • f$ pmsqrt{left( 3 + 2sqrt{6/5} right)/7} f$ –> f$ (18-sqrt{30})/36 f$

  • n = 5:

  • f$ 0 f$ –> f$ 128/225 f$

  • f$ pmfrac{1}{3}sqrt{5-2sqrt{10/7}} f$ –> f$ (322+13sqrt{70})/900 f$

  • f$ pmfrac{1}{3}sqrt{5+2sqrt{10/7}} f$ –> f$ (322-13sqrt{70})/900 f$

Parameters

n – Number of quadrature points

Returns lists

points and corresponding weights, sorted by points value

pyNastran.utils.mathematics.get_abs_index(data, axis=1)[source]

Gets the maximum absolute value of a 2D matrix along an axis

Examples

>>> data = [
        [4.0, 2.2, 3.0, 5.0, 2.2]  # subcase 1
        [4.1, 2.1, 3.1, 5.1, 2.1], # subcase 2
    ]
>>> max_values, index = get_min_index(data, axis=1)
>>> out
[4.1, 2.2, 3.1, 5.1, 2.2]
>>> index
[1, 0, 1, 1, 0]
pyNastran.utils.mathematics.get_abs_max(min_values, max_values, dtype='float32')[source]

Get return the value with the greatest magnitude, preserving sign.

pyNastran.utils.mathematics.get_max_index(data, axis=1)[source]

Gets the maximum values of a 2D matrix along an axis

Examples

>>> data = [
        [4.0, 2.2, 3.0, 5.0, 2.2]  # subcase 1
        [4.1, 2.1, 3.1, 5.1, 2.1], # subcase 2
    ]
>>> max_values, index = get_max_index(data, axis=1)
>>> out
[4.1, 2.2, 3.1, 5.1, 2.2]
>>> index
[1, 0, 1, 1, 0]
pyNastran.utils.mathematics.get_min_index(data, axis=1)[source]

Gets the minimum values of a 2D matrix along an axis

Examples

>>> data = [
        [4.0, 2.2, 3.0, 5.0, 2.2]  # subcase 1
        [4.1, 2.1, 3.1, 5.1, 2.1], # subcase 2
    ]
>>> min_values, index = get_min_index(data, axis=1)
>>> out
[4.0, 2.1, 3.0, 5.0, 2.1]
>>> index
[0, 1, 0, 0, 1]
pyNastran.utils.mathematics.integrate_positive_unit_line(x, y, min_value=0.0)[source]

Integrates a line of length 1.0 by linear interpolation

Parameters
xList[float]

the independent variable

yList[float]

the dependent variable

min_valuefloat; default=0.0

???

Returns
integrated_valuefloat

the area under the curve

pyNastran.utils.mathematics.integrate_unit_line(x, y)[source]

Integrates a line of length 1.0 by linear interpolation

Parameters
xList[float]

the independent variable

yList[float]

the dependent variable

Returns
integrated_valuefloat

the area under the curve

pyNastran.utils.mathematics.is_float_ranged(a, x, b)[source]

Returns true if a<= x <= b or a-x < 0 < b-x.

Parameters
afloat

the lower bound value (inclusive)

xList[float, …]

the search values

b: float

the upper bound value (inclusive)

Returns
is_rangedbool

True/False

pyNastran.utils.mathematics.is_list_ranged(a, List, b)[source]

Returns true if a<= x <= b or a-x < 0 < b-x

Parameters
afloat

the lower bound value (inclusive)

xList[float, …]

the search values

b: float

the upper bound value (inclusive)

Returns
is_rangedbool

True/False

pyNastran.utils.mathematics.list_print(list_a, tol=1e-08, float_fmt='%-3.2g', zero_fmt=' 0')[source]

prints a list / numpy array in a readable format

pyNastran.utils.mathematics.print_annotated_matrix(A, row_names=None, col_names=None, tol=1e-08)[source]

Takes a list/dictionary and annotates the row number with that value indicies go from 0 to N

pyNastran.utils.mathematics.print_matrix(A, tol=1e-08)[source]

prints a 2d matrix in a readable format

pyNastran.utils.mathematics.reduce_matrix(matrix_a, nids)[source]

takes a list of ids and removes those rows and cols

pyNastran.utils.mathematics.roundup(value, round_increment=100)[source]

Rounds up to the next N.

Parameters
valueint

the value to round up

round_incrementint

the increment to round by

.. python
>>> 100 = roundup(10)
>>> 200 = roundup(105)
>>> 300 = roundup(200)
>>> 1000 = roundup(200, 1000)
>>> 2000 = roundup(1000, 1000)
>>> 2000 = roundup(1001, 1000)
.. note: this function is used to ensure that renumbering is more

obvious when testing

nastran_utils Module

pyNastran.utils.nastran_utils.run_nastran(bdf_filename: str, nastran_cmd: str = 'nastran', keywords: Union[str, List[str], Dict[str, str], None] = None, run: bool = True, run_in_bdf_dir: bool = True) → Tuple[Optional[int], List[str]][source]

Call a nastran subprocess with the given filename

Parameters
bdf_filenamestring

Filename of the Nastran .bdf file

keywordsstr/dict/list of strings, optional

Default keywords are ‘scr=yes’, ‘bat=no’, ‘old=no’, and ‘news=no’

runbool; default=True

let’s you disable actually running Nastran to test out code/get the call arguments

run_in_local_dirbool; default=True

True : output (e.g., *.f06) will go to the current working directory (default) False : outputs (e.g., *.f06) will go to the input BDF directory

Returns
return_codeint

the nastran flag

cmd_argsList[str]

the nastran commands that go into subprocess

numpy_utils Module

Interface to various numpy utilities

pyNastran.utils.numpy_utils.zip_strict(*arrays)[source]

__init__ Module

defines:
  • deprecated(old_name, new_name, deprecated_version, levels=None)

  • print_bad_path(path)

  • object_attributes(obj, mode=’public’, keys_to_skip=None)

  • object_methods(obj, mode=’public’, keys_to_skip=None)

pyNastran.utils.__init__.b(string: str) → bytes[source]

reimplementation of six.b(…) to work in Python 2

pyNastran.utils.__init__.check_path(filename: str, name: str = 'file') → None[source]

checks that the file exists

pyNastran.utils.__init__.int_version(name: str, version: str) → List[int][source]

splits the version into a tuple of integers

pyNastran.utils.__init__.ipython_info() → Optional[str][source]

determines if iPython/Jupyter notebook is running

pyNastran.utils.__init__.is_binary_file(filename: Union[str, pathlib.PurePath]) → bool[source]

Return true if the given filename is binary.

Parameters
filenamestr

the filename to test

Returns
binary_flagbool

True if filename is a binary file (contains null byte) and False otherwise.

raises

IOError if the file cannot be opened. ..

Based on the idea (.. seealso:: http://bytes.com/topic/python/answers/21222-determine-file-type-binary-text)
that file is binary if it contains null.

Warning

this may not work for unicode. ..

pyNastran.utils.__init__.is_file_obj(filename: str) → bool[source]

does this object behave like a file object?

pyNastran.utils.__init__.object_attributes(obj: Any, mode: str = 'public', keys_to_skip: Optional[List[str]] = None, filter_properties: bool = False) → List[str][source]

List the names of attributes of a class as strings. Returns public attributes as default.

Parameters
objinstance

the object for checking

modestr

defines what kind of attributes will be listed * ‘public’ - names that do not begin with underscore * ‘private’ - names that begin with single underscore * ‘both’ - private and public * ‘all’ - all attributes that are defined for the object

keys_to_skipList[str]; default=None -> []

names to not consider to avoid deprecation warnings

filter_properties: bool: default=False

filters the @property objects

Returns
attribute_namesList[str]

sorted list of the names of attributes of a given type or None if the mode is wrong

pyNastran.utils.__init__.object_methods(obj: Any, mode: str = 'public', keys_to_skip: Optional[List[str]] = None) → List[str][source]

List the names of methods of a class as strings. Returns public methods as default.

Parameters
objinstance

the object for checking

modestr

defines what kind of methods will be listed * “public” - names that do not begin with underscore * “private” - names that begin with single underscore * “both” - private and public * “all” - all methods that are defined for the object

keys_to_skipList[str]; default=None -> []

names to not consider to avoid deprecation warnings

Returns
methodList[str]

sorted list of the names of methods of a given type or None if the mode is wrong

pyNastran.utils.__init__.object_stats(obj: Any, mode: str = 'public', keys_to_skip: Optional[List[str]] = None, filter_properties: bool = False) → str[source]

Prints out an easy to read summary of the object

pyNastran.utils.__init__.print_bad_path(path: str) → str[source]

Prints information about the existence (access possibility) of the parts of the given path. Useful for debugging when the path to a given file is wrong.

Parameters
pathstr

path to check

Returns
msgstr

string with information whether access to parts of the path is possible

pyNastran.utils.__init__.remove_files(filenames)[source]

remvoes a series of files; quietly continues if the file can’t be removed