D3plot

Ressources:
class qd.cae.dyna.D3plot(filepath, read_states=[], use_femzip=False)
Parameters
filepathstr

path to the d3plot

read_statesstr or list of str

read state information directly (saves time), see the function read_states

use_femzipbool

whether the file shall be decompressed with femzip.

Returns
D3plot d3plotinstance
Raises
ValueError

in case of an invalid filepath or locked file

RuntimeError

if anything goes wrong (internal checks) during reading

Notes

If LS-Dyna writes multiple files (one for each timestep), give the filepath to the first file. The library finds all other files. Please read state information with the read_states flag in the constructor or with the member function.

Examples

Read the plain geometry data

>>> d3plot = D3plot("path/to/d3plot")

Read a compressed d3plot

>>> d3plot = D3plot("path/to/d3plot.fz", use_femzip=True)

Read d3plot with state data at once.

>>> d3plot = D3plot("path/to/d3plot", read_states=["mises_stress max"])

Methods

clear(vars)

Parameters

compare_scatter(self, filepath_list, …[, …])

Compare the scatter between mutliple d3plot files

get_elementByIndex(element_type, index)

Parameters

get_element_coords(element_filter)

Parameters

get_element_energy(element_filter)

Parameters

get_element_history_vars(element_type)

Parameters

get_element_ids(element_filter)

Parameters

get_element_node_ids(element_type, n_nodes)

Parameters

get_element_plastic_strain(element_filter)

Parameters

get_element_strain(element_filter)

Parameters

get_element_stress(element_filter)

Parameters

get_element_stress_mises(element_filter)

Parameters

get_elements([element_filter])

Parameters

get_filepath()

Returns

get_nElements([element_filter])

Parameters

get_nNodes()

Returns

get_nParts()

Returns

get_nTimesteps()

Get the number of timesteps of the d3plot.

get_nodeByID(id)

Parameters

get_nodeByIndex(index)

Parameters

get_node_acceleration()

Returns

get_node_coords()

Returns

get_node_ids()

Returns

get_node_velocity()

Returns

get_nodes()

Returns

get_partByID(id)

Parameters

get_partByIndex(index)

Parameters

get_partByName(name)

Parameters

get_parts()

Returns

get_timesteps()

Get the simulation time of the written states.

get_title()

Get the title of the d3plot, which is part of the header data.

info()

Prints a summary of the header data of the D3plot, which involves node info, element info, written state data and so forth.

plot(self[, iTimestep, element_result, …])

Plot the D3plot, currently shells only!

plot_parts(parts[, iTimestep, …])

Plot a selected group of parts.

read_states(vars)

Parameters

get_elementByID
__init__(filepath, read_states=[], use_femzip=False)
Parameters
filepathstr

path to the d3plot

read_statesstr or list of str

read state information directly (saves time), see the function read_states

use_femzipbool

whether the file shall be decompressed with femzip.

Returns
D3plot d3plotinstance
Raises
ValueError

in case of an invalid filepath or locked file

RuntimeError

if anything goes wrong (internal checks) during reading

Notes

If LS-Dyna writes multiple files (one for each timestep), give the filepath to the first file. The library finds all other files. Please read state information with the read_states flag in the constructor or with the member function.

Examples

Read the plain geometry data

>>> d3plot = D3plot("path/to/d3plot")

Read a compressed d3plot

>>> d3plot = D3plot("path/to/d3plot.fz", use_femzip=True)

Read d3plot with state data at once.

>>> d3plot = D3plot("path/to/d3plot", read_states=["mises_stress max"])
clear(vars)
Parameters
varsstr or list(str)

variable or list of variables to delete

Notes

This function may be used if one wants to clear certain state data from the memory. Valid variable names are:

  • disp

  • vel

  • accel

  • strain

  • stress

  • stress_mises

  • plastic_strain

  • history [(optional) shell or solid]

The specification of shell or solid for history is optional. Deletes all history variables if none given.

Examples

>>> d3plot = D3plot("path/to/d3plot", read_states="strain inner")
>>> elem = d3plot.get_elementByID(Element.shell, 1)
>>> len( elem.get_strain() )
34
>>> # clear specific field
>>> d3plot.clear("strain")
>>> len( elem.get_strain() )
0
>>> # reread some data
>>> d3plot.read_states("strain outer")
>>> len( elem.get_strain() )
34
>>> d3plot.clear() # clear all
>>> len( elem.get_strain() )
0
compare_scatter(self, filepath_list, element_result, pid_filter_list=None, kMappingNeighbors=4, export_filepath=None, **kwargs)

Compare the scatter between mutliple d3plot files

Parameters
filepath_listlist(str)

list of filepaths of d3plot for comparison

element_resultstr or function(element)

element results to compare. Either specify a user defined function or use predefined results. Available are disp, plastic_strain or energy.

pid_filter_listlist(int)

list of pids to filter for optionally

kMappingNeighborsint

number of neighbors used for nearest neighbor mapping

export_filepathstr

optional filepath for saving. If none, the model is exported to a temporary file and shown in the browser.

**kwargsfurther arguments

additional arguments passed on to d3plot constructor (e.g. read_states)

Notes

The file calling the function will be the basis for the comparison. The other files results will be mapped onto this mesh. The scatter is computed between all runs as maximum difference.

Examples

>>> # Settings (don't forget to load the correct vars!)
>>> state_vars = ["stress_mises max"]
>>> other_files = ["path/to/d3plot_2", "path/to/d3plot_3"]
>>>
>>> # Element eval function (used for scatter computation)
>>> def elem_eval_fun(elem):
>>>     result = elem.get_stress_mises()
>>>     if len(result):
>>>         return result[-1]
>>>     return 0.
>>>
>>> # load base file
>>> d3plot = D3plot("path/to/d3plot", read_states=state_vars)
>>> 
>>> # compute and plot scatter
>>> d3plot.compare_scatter(other_files, elem_eval_fun, read_states=state_vars)
get_elementByIndex(element_type, index)
Parameters
element_typeElement.type

type of the element. Must be beam, shell or solid.

indexint or list(int)

element index or list of indexes

Returns
elementElement

Element(s) depending on the arguments

Raises
ValueError

if invalid element_type is given or index does not exist

Examples

>>> # single element
>>> elem = femfile.get_elementByIndex(Element.shell, 0)
>>> # multiple elements
>>> list_of_shells = femfile.get_elementByID(Element.shell, [0,1,2])
>>> 
>>> femfile.get_elementByIndex(Element.beam, 1).get_type()
type.beam
>>> femfile.get_elementByIndex(Element.solid, 1).get_type()
type.solid
>>> femfile.get_elementByIndex(Element.tshell, 1).get_type()
type.tshell
get_element_coords(element_filter)
Parameters
element_filterElement.type

optional type for filtering

Returns
fieldnp.ndarray

coords vector of the elements (nElems x nTimesteps x 3)

Notes

If an element does not have the respective result, 0 is set as default value.

Examples

>>> d3plot = D3plot("path/to/d3plot", read_states="coords")
>>> d3plot.get_nElements(Element.shell)
4969
>>> d3plot.get_nTimesteps()
32
>>> d3plot.get_element_coords(Element.shell).shape
(4969, 32. 3)
get_element_energy(element_filter)
Parameters
element_filterElement.type

optional type for filtering

Returns
fieldnp.ndarray

energy of the elements (nElems x nTimesteps)

Notes

If an element does not have the respective result, 0 is set as default value.

Examples

>>> d3plot = D3plot("path/to/d3plot", read_states="energy mean")
>>> d3plot.get_nElements(Element.shell)
4969
>>> d3plot.get_nTimesteps()
32
>>> d3plot.get_element_energy(Element.shell).shape
(4969, 32)
get_element_history_vars(element_type)
Parameters
element_typeElement.type

type of the element

Returns
fieldnp.ndarray

history_vars vector of the elements (nElems x nTimesteps x nHistoryVars)

Notes

IMPORTANT: You can not query the history vars without specifying an element type. In LS-Dyna e.g. history var 7 is different between shells and beams. To prevent wrong usage and bugginess, we enforce this policy here. We didn’t mess this one up!

If an element does not have the respective result, 0 is set as default value.

Examples

>>> d3plot = D3plot("path/to/d3plot", read_states="shell history 7 max")
>>> d3plot.get_nElements(Element.shell)
4969
>>> d3plot.get_nTimesteps()
32
>>> # Element type is required here!
>>> d3plot.get_element_history_vars(Element.shell).shape
(4969, 32. 10)
get_element_ids(element_filter)
Parameters
element_filterElement.type

optional element type for filtering

Returns
element_idsnp.ndarray

Ids of the elements

Notes

If the ids for all elements are queried (Element.none as filter type) then the returned order is:

  • Element.beam

  • Element.shell

  • Element.solid

  • Element.tshell

Examples

>>> d3plot = D3plot("path/to/d3plot")
>>> # get all ids (beam, shell, solid, tshell)
>>> d3plot.get_element_ids()
array([4687, 4688, 4689, 4690, ...])
>>> # filter only beams
>>> d3plot.get_element_ids(Element.beam)
array([9545, 9546, 9547, 9511, ...])
get_element_node_ids(element_type, n_nodes)
Parameters
element_typeElement.type

type of the element

n_nodesint

number of nodes

Returns
element_node_idsnp.ndarray

ids of the nodes for every element (shape elems x n_nodes).

Notes

The number of nodes must be specified since elements of one type may have different number of nodes which would result in a non-uniform matrix.

Examples

>>> d3plot = D3plot("path/to/d3plot")
>>> d3plot.get_element_node_ids(Element.shell, 4)
array([[347, 354, 343, 344],
       [354, 355, 342, 343],
       [349, 352, 356, 348]], dtype=int32)
get_element_plastic_strain(element_filter)
Parameters
element_filterElement.type

optional type for filtering

Returns
fieldnp.ndarray

effective plastic strain of the elements (nElems x nTimesteps)

Notes

If an element does not have the respective result, 0 is set as default value.

Examples

>>> d3plot = D3plot("path/to/d3plot", read_states="plastic_strain max")
>>> d3plot.get_nElements(Element.shell)
4969
>>> d3plot.get_nTimesteps()
32
>>> d3plot.get_plastic_strain(Element.shell).shape
(4969, 32)
get_element_strain(element_filter)
Parameters
element_filterElement.type

optional type for filtering

Returns
fieldnp.ndarray

strain vector of the elements (nElems x nTimesteps x 6)

Notes

If an element does not have the respective result, 0 is set as default value.

Examples

>>> d3plot = D3plot("path/to/d3plot", read_states="strain mean")
>>> d3plot.get_nElements(Element.shell)
4969
>>> d3plot.get_nTimesteps()
32
>>> d3plot.get_element_strain(Element.shell).shape
(4969, 32. 6)
get_element_stress(element_filter)
Parameters
element_filterElement.type

optional type for filtering

Returns
fieldnp.ndarray

stress vector of the elements (nElems x nTimesteps x 6)

Notes

If an element does not have the respective result, 0 is set as default value.

Examples

>>> d3plot = D3plot("path/to/d3plot", read_states="stress mean")
>>> d3plot.get_nElements(Element.shell)
4969
>>> d3plot.get_nTimesteps()
32
>>> d3plot.get_element_stress(Element.shell).shape
(4969, 32. 6)
get_element_stress_mises(element_filter)
Parameters
element_filterElement.type

optional type for filtering

Returns
fieldnp.ndarray

mises stress of the elements (nElems x nTimesteps)

Notes

If an element does not have the respective result, 0 is set as default value.

Examples

>>> d3plot = D3plot("path/to/d3plot", read_states="stress_mises mean")
>>> d3plot.get_nElements(Element.shell)
4969
>>> d3plot.get_nTimesteps()
32
>>> d3plot.get_element_stress_mises(Element.shell).shape
(4969, 32)
get_elements(element_filter=Element.none)
Parameters
element_filterElement.type

Optional element type filter. May be beam, shell or solid.

Returns
elementslist(Element)

list of Elements

Raises
ValueError

if invalid element_filter is given.

Notes

Get the elements of the femfile. One may use a filter by type.

Examples

>>> all_elements = femfile.get_elements()
>>> shell_elements = femfile.get_elements(Element.shell)
get_filepath()
Returns
filepathstr

Filepath of the femfile.

Examples

>>> femfile.get_filepath()
"path/to/femfile"
get_nElements(element_filter=Element.none)
Parameters
element_filterElement.type

Optional element type filter. May be beam, shell or solid.

Returns
nElementsint

number of elements

Raises
ValueError

if invalid element_filter is given.

Examples

>>> femfile.get_nElements()
43156
get_nNodes()
Returns
nNodesint

number of nodes in the file

Examples

>>> femfile.get_nNodes()
43145
get_nParts()
Returns
nPartsint

number of parts in the database

Examples

>>> femfile.get_nParts()
7
get_nTimesteps()

Get the number of timesteps of the d3plot.

Returns
nTimestepsint

number of timesteps

Examples

>>> d3plot = D3plot("path/to/d3plot")
>>> d3plot.get_nTimesteps()
32
get_nodeByID(id)
Parameters
idint or list(int)

node id or list of node ids

Returns
nodeNode or list(Node)

requested Node(s)

Raises
ValueError

if idx does not exist.

Examples

>>> # get by single id
>>> node = femfile.get_nodeByID(1)
>>> # get a list of nodes at once
>>> list_of_nodes = femfile.get_nodeByID( [1,2,3] )
get_nodeByIndex(index)
Parameters
indexint or list(int)

internal node index or list inf indexes

Returns
nodeNode or list(Node)

Node(s)

Raises
ValueError

if index larger femfile.get_nNodes().

Notes

The internal index starts at 0 and ends at femfile.get_nNodes().

Examples

>>> # single index
>>> node = femfile.get_nodeByIndex(1)
>>> # get a list of nodes at once
>>> list_of_nodes = femfile.get_nodeByIndex( [1,2,3] )
get_node_acceleration()
Returns
node_accelerationnp.ndarray

Accelration of all nodes

Examples

>>> d3plot.get_node_acceleration().shape
(4915,1,3)
get_node_coords()
Returns
node_coordsnp.ndarray

coordinates of all nodes

Examples

>>> d3plot.get_node_coords().shape
(4915, 3)
get_node_ids()
Returns
node_idsnp.ndarray

Ids of all nodes

Examples

>>> d3plot.get_node_ids().shape
(100001)
get_node_velocity()
Returns
node_velocitynp.ndarray

Velocity of all nodes

Examples

>>> d3plot.get_node_velocity().shape
(4915,1,3)
get_nodes()
Returns
nodeslist(Node)

list of node objects

Examples

>>> list_of_nodes = femfile.get_nodes()
get_partByID(id)
Parameters
idint or list of int

id or ids of the part in the file

Returns
partsPart or list of Parts

output depending on arguments

Raises
ValueError

if some id does not exist.

Examples

>>> part = femfile.get_partByID(1)
get_partByIndex(index)
Parameters
indexint or list of int

index or indexes of the part in the file

Returns
partsPart or list of Parts

output depending on arguments

Raises
ValueError

if some index does not exist.

Examples

>>> part = femfile.get_partByIndex(0)
get_partByName(name)
Parameters
namestr

name of the part

Returns
partsPart

part with the given name

Raises
ValueError

if a part with name does not exist.

Examples

>>> part = femfile.get_partByName("Lower Bumper")
get_parts()
Returns
partslist(Part)

list of all parts in the file

Examples

>>> list_of_all_parts = femfile.get_parts()
get_timesteps()

Get the simulation time of the written states.

Returns
timestepsnp.ndarray

state timesteps of the D3plot

Examples

>>> d3plot = D3plot("path/to/d3plot")
>>> time = d3plot.get_timesteps()
get_title()

Get the title of the d3plot, which is part of the header data.

Returns
titlestr

the title of the d3plot

Examples

>>> d3plot = D3plot("path/to/d3plot")
>>> d3plot.get_title()
"Barrier Impact"
info()

Prints a summary of the header data of the D3plot, which involves node info, element info, written state data and so forth.

Examples

>>> d3plot = D3plot("path/to/d3plot")
>>> d3plot.info()
plot(self, iTimestep=0, element_result=None, fringe_bounds=[None, None], export_filepath=None)

Plot the D3plot, currently shells only!

Parameters
iTimestepint

timestep at which to plot the D3plot

element_resultstr or function

which type of results to use as fringe None means no fringe is used. When using string as arg you may use plastic_strain or energy. Function shall take elem as input and return a float value (for fringe)

fringe_boundslist(float,float) or tuple(float,float)

bounds for the fringe, default will use min and max value

export_filepathstr

optional filepath for saving. If none, the model is exported to a temporary file and shown in the browser.

Examples

Load a d3plot and plot it’s geometry

>>> d3plot = D3plot("path/to/d3plot")
>>> d3plot.plot() # just geometry

Read the state data and plot in deformed state

>>> # read state data
>>> d3plot.read_states(["disp","plastic_strain max"])
>>> d3plot.plot(iTimestep=-1) # last state

Use a user-defined element evaluation function for fringe colors.

>>> # User defined evaluation function
>>> def eval_fun(element):
>>>     res = element.get_plastic_strain()
>>>     if len(res): # some elements may miss plastic strain
>>>         return res[-1] # last timestep
>>> 
>>> d3plot.plot(iTimestep=-1, element_result=eval_fun, fringe_bounds=[0, 0.05])
static plot_parts(parts, iTimestep=0, element_result=None, fringe_bounds=[None, None], export_filepath=None)

Plot a selected group of parts.

Parameters
partsPart or list(Part)

parts to plot. May be from different files.

iTimestepint

timestep at which to plot the D3plot

element_resultstr or function

which type of results to use as fringe None means no fringe is used When using string as arg you may use plastic_strain or energy. Function shall take elem as input and return a float value (for fringe)

fringe_boundslist(float,float) or tuple(float,float)

bounds for the fringe, default will use min and max value

export_filepathstr

optional filepath for saving. If none, the model is exported to a temporary file and shown in the browser.

Notes

Can be applied to parts, coming from different files.

Examples

For a full description of plotting functionality, see d3plot.plot. Load a d3plot and plot a part from it:

>>> d3plot_1 = D3plot("path/to/d3plot_1")
>>> part_1 = d3plot_1.get_partByID(1)
>>> D3plot.plot_parts( [part_1] ) # static function!

Read a second d3plot and plot both parts at once

>>> d3plot_2 = D3plot("path/to/d3plot_2") # different file!
>>> part_2 = d3plot_2.get_partByID(14)
>>> D3plot.plot_parts( [part_1, part_2] )
read_states(vars)
Parameters
varsstr or list(str)

variable or list of variables to read (see Notes below)

Notes

Read a variable from the state files. If this is not done, the nodes and elements return empty vectors when requesting a result. The variables available are:

  • disp (displacement)

  • vel (velocity)

  • accel (acceleration)

  • strain [(optional) mode]

  • stress [(optional) mode]

  • stress_mises [(optional) mode]

  • plastic_strain [(optional) mode]

  • history [id1] [id2] [shell or solid] [(optional) mode]

There is an optional mode for the element results. The results are only given at the center of an element. Since shell elements have multiple layers of results, the optional mode determines the treatment of these layers:

  • inner (first layer)

  • mid (middle)

  • outer (last layer)

  • mean

  • max

  • min

Examples

>>> d3plot = D3plot("path/to/d3plot") # just geometry
>>> node = d3plot.get_nodeByID(1)
>>> len( node.get_disp() ) # no disps loaded
0
>>> # Read displacements
>>> d3plot.read_states("disp")
>>> len( node.get_disp() ) # here they are
31
>>> # multi-loading, already loaded will be skipped
>>> d3plot.read_states(["disp","vel","stress_mises max","shell history 1 mean"])
>>> # most efficient way, load the results directly when opening
>>> D3plot("path/to/d3plot", read_states=["disp","vel","plastic_strain max"])