# wall history command

Syntax

wall history <name sid > keyword ...

Primary keywords:

Adds a history of a wall value. A history is a table of floating point values assigned by sampling a model attribute periodically during a simulation. Review the common c history commands for details regarding the manipulation of histories.

The history can be assigned a name for later reference with the optional name keyword, if not the history will be given a default name based on its internally assigned id number.

Following one of the keywords given below, either 1) an additional id keyword followed by an integer id, 2) an additional name keyword followed by a string s, or 3) an additional position keyword followed by a position vector v must be given to define the specific wall.

displacement [wallhistoryblock]

Magnitude of the accumulated wall displacement vector as a result of cycling.

displacement-x [wallhistoryblock]

The $$x$$-component of accumulated displacement as a result of cycling.

displacement-y [wallhistoryblock]

The $$y$$-component of accumulated displacement as a result of cycling.

displacement-z (3D ONLY) [wallhistoryblock]

The $$z$$-component of accumulated displacement as a result of cycling.

euler-x (3D ONLY) [wallhistoryblock]

The $$x$$-euler angle (in degrees) of the current wall orientation. The orientation is updated only when orientation tracking has been enabled (see the model orientation-tracking command). See the euler keyword of the wall attribute command.

euler-y (3D ONLY) [wallhistoryblock]

The $$y$$-euler angle (in degrees) of the current wall orientation. The orientation is updated only when orientation tracking has been enabled (see the model orientation-tracking command). See the euler keyword of the wall attribute command.

euler-z (3D ONLY) [wallhistoryblock]

The $$z$$-euler angle (in degrees) of the current wall orientation. The orientation is updated only when orientation tracking has been enabled (see the model orientation-tracking command). See the euler keyword of the wall attribute command.

extra [wallhistoryblock]

Take a history of an extra variable. Use index to specify the extra index and type to specify the type.

force-contact [wallhistoryblock]

The magnitude of the force resulting from contacts.

force-contact-x [wallhistoryblock]

The $$x$$-component of the contact force.

force-contact-y [wallhistoryblock]

The $$y$$-component of the contact force.

force-contact-z (3D ONLY) [wallhistoryblock]

The $$z$$-component of the contact force.

moment-contact [wallhistoryblock]

{Value in 2D; Magnitude in 3D} of the sum of the contact moments.

moment-contact-x (3D ONLY) [wallhistoryblock]

The $$x$$-component of the contact moment.

moment-contact-y (3D ONLY) [wallhistoryblock]

The $$y$$-component of the contact moment.

moment-contact-z (3D ONLY) [wallhistoryblock]

The $$z$$-component of the contact moment.

position-x [wallhistoryblock]

The $$x$$-component of the location of wall centroid.

position-y [wallhistoryblock]

The $$y$$-component of the location of wall centroid.

position-z (3D ONLY) [wallhistoryblock]

The $$z$$-component of the location of wall centroid.

rotation (2D ONLY) [wallhistoryblock]

Current wall orientation. The orientation is updated only when orientation tracking has been enabled (see model orientation-tracking command).

spin [wallhistoryblock]

{Value in 2D; Magnitude in 3D} of the wall angular velocity in radians per second.

spin-x (3D ONLY) [wallhistoryblock]

The $$x$$-component of the wall angular velocity in radians per second.

spin-y (3D ONLY) [wallhistoryblock]

The $$y$$-component of the wall angular velocity in radians per second.

spin-z (3D ONLY) [wallhistoryblock]

The $$z$$-component of the wall angular velocity in radians per second.

velocity [wallhistoryblock]

Magnitude of the wall translational velocity vector.

velocity-x [wallhistoryblock]

The $$x$$-component of the wall velocity.

velocity-y [wallhistoryblock]

The $$y$$-component of the wall velocity.

velocity-z (3D ONLY) [wallhistoryblock]

The $$z$$-component of the wall velocity.

wall history Keyword Block

The following modifiers are available to specify addition information for the wall history keywords. They will not modify history values to which they are not applicable. In other words, the component keyword will not modify scalar or tensor values. displacement, displacement-x, displacement-y, displacement-z, euler-x, euler-y, euler-z, extra, force-contact, force-contact-x, force-contact-y, force-contact-z, moment-contact, moment-contact-x, moment-contact-y, moment-contact-z, position-x, position-y, position-z, rotation, spin, spin-x, spin-y, spin-z, velocity, velocity-x, velocity-y and velocity-z.

component keyword

This keyword selects which scalar to retrieve from a vector type value, such as velocity or displacement. If the value type is not a vector, this setting is ignored. The available options are:

x
Record the $$x$$-component of the vector.
y
Record the $$y$$-component of the vector.
z (3D ONLY)
Record the $$z$$-component of the vector.
magnitude
Record the vector magnitude.
id i

Record the history of wall with ID i.

index i

For keywords that require it (most notably extra), this specifies the index that should be used.

log b

If on, the returned number is the base 10 log of the absolute value of the original value. The default is off.

name s

Record the history of wall with name s.

position v

Record the history of wall either containing or closest to position v.

quantity keyword

This keyword selects which scalar to retrieve from a symmetric tensor type value, such as stress or strain. If the value type is not a tensor, this setting is ignored. The available options are:

intermediate (3D ONLY)

Record the intermediate principal value of the tensor.

maximum

Record the maximum (most positive) principal value of the tensor. Note that compressive stresses are negative.

mean

Record the mean value, defined as the trace of the tensor divided by { 2 in 2D; 3 in 3D}. For stresses this is most often referred to as the pressure.

minimum

Record the minimum (most negative) principal value of the tensor. Note that compressive stresses are negative.

norm

Record the norm of the full tensor. This is defined as the sum of each tensor component squared.

octahedral (3D ONLY)

Record the octahedral measure of the tensor.

shear-maximum

Record the maximum shear value.

total-measure (3D ONLY)

Record the distance of the tensor value to the origin in principal space.

volumetric

Record the volumetric change, or trace of the tensor.

von-mises (3D ONLY)

Record the Von Mises measure.

xx

Record the xx-component of the tensor.

xy

Record the xy-component of the tensor.

xz (3D ONLY)

Record the xz-component of the tensor.

yy

Record the yy-component of the tensor.

yz (3D ONLY)

Record the yz-component of the tensor.

zz (3D ONLY)

Record the zz-component of the tensor.

type keyword

In certain cases the type (scalar, vector, or tensor) of the value cannot necessarily be determined ahead of time. Extra variables, for example, can hold values of all three types. This keyword allows one to specify which type it is assumed to be. If the original value type does not match, 0.0 is returned.

scalar

Specify a scalar float type.

tensor

Specify a tensor type.

vector

Specify a vector type.

Usage Examples

Record the $$y$$-component of displacement of the wall with ID 2.

wall history displacement-y id 2


from “inclusions.dat” in Inclusions in a Matrix

Record the contact force on wall with ID 2 and name the history 3.

wall history name '3' force-contact id 2


from “fragment.dat” in Fragmentation Analysis during a Uniaxial Compression with Crack Tracking Using Fractures