Shape Data Attributes

Shape Data Attributes (sorted by subject)

AbscissaAxisLab

This is a character string of maximum length 20 that can be used to override the default Abscissa axis label. It is used only with operating deflection shapes.

AbscissaUnitsLab

This is a character string of maximum length 20 that can be used to override the default Abscissa units label. It is used only with operating deflection shapes.

CreateDate

Lists the date that the shape was created. It is automatically stored when the shape is created. While it can be modified in MATLAB, it will be overwritten when exported to an ADF. It is stored as a character string of length 20, in the format "DD-MMM-YY HH:MM:SS".

CSType

This attribute defines the coordinate system type in which the shape coefficients are defined. The available data types and their corresponding numeric identifier are shown in the table below.

This attribute is an IMAT-specific property. The Universal file format does not contain a location to store this attribute, so this property will not round-trip through Universal files. It is stored in the ASH file, and will round-trip in IMAT through the ASH format, but other software that recognizes the ASH format will not recognize this attribute and may overwrite it.

Numeric Identifier	Data Type
0	Displacement
1	Basic (global)
2	Other

DOFType

This attribute defines the number of degrees of freedom per node, which affects the Shape coefficient storage. The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
3	`'3DOF'` [X,Y,Z (translational only)]
6	`'6DOF'` [X,Y,Z,RX,RY,RZ (translational and rotational)]

Damping

Defines the damping of the mode as a fraction of critical damping. For example, 1% of critical damping is stored as 0.01.

Frequency

Defines the undamped natural frequency of the mode in Hertz.

IDLine1

This is also called the shape Title. It is limited to 80 characters.

IDLine2

The second shape descriptor line. It is limited to 80 characters.

IDLine3

The third shape descriptor line. It is limited to 40 characters.

IDLine4

The fourth shape descriptor line. It is limited to 80 characters.

IDLine5

The fifth shape descriptor line. It is limited to 80 characters.

ModalDampingImag

Specifies the imaginary part of the modal damping for this mode. This attribute is not set by I-deas until you explicitly normalize the mode, or until you export the shape to a universal file.

For a real mode, this attribute is not used. For a complex mode, ModalDampingImag holds the imaginary part of the "modal B" for this complex mode. For more information, read the "Complex Mode Solution" article in I-deas SmartView.

Modal damping is considered to have the same units as the shape coefficients (defined by OrdNumDataType and OrdDenDataType).

ModalDampingReal

Specifies the real part of the modal damping for this mode. This attribute is not set by I-deas until you explicitly normalize the mode, or until you export the shape to a universal file.

For a real mode, this attribute is not used. For a complex mode, ModalDampingReal holds the real part of the "modal B" for this complex mode. For more information, read the "Complex Mode Solution" article in I-deas SmartView.

Modal damping is considered to have the same units as the shape coefficients (defined by OrdNumDataType and OrdDenDataType).

ModalMassImag

Specifies the imaginary part of the modal mass for this mode. This attribute is not set by I-deas until you explicitly normalize the mode, or until you export the shape to a universal file.

For a real mode, the ModalMassImag is zero, and ModalMassReal is the modal mass of the mode. For a complex mode, ModalMassImag holds the imaginary part of the "modal A" for this complex mode. For more information, read the "Complex Mode Solution" article in I-deas SmartView.

Modal mass is considered to have the same units as the shape coefficients (defined by OrdNumDataType and OrdDenDataType).

ModalMassReal

Specifies the real part of the modal mass for this mode. This attribute is not set by I-deas until you explicitly normalize the mode, or until you export the shape to a universal file.

For a real mode, the ModalMassImag is zero, and ModalMassReal is the modal mass of the mode. For a complex mode, ModalMassReal holds the real part of the "modal A" for this complex mode. For more information, read the "Complex Mode Solution" article in I-deas SmartView.

Modal mass is considered to have the same units as the shape coefficients (defined by OrdNumDataType and OrdDenDataType).

ModifyDate

Lists the date that the shape was last modified. It is automatically updated when the shape is modified. While it can be modified in MATLAB, it will be overwritten when exported to an ADF. It is stored as a character string of length 20, in the format "DD-MMM-YY HH:MM:SS".

Nodes

Integer column vector of node labels for which Shape coefficients are stored.

NumberNodes

Specifies the number of nodes used in the mode shape definition. This defines the size of Nodes, and when multiplied by DOFType, defines the size of Shape.

OrdDenDataType

Defines the data type for the ordinate denominator of the frequency response functions from which the shape was defined (mode shapes are considered to be in the same units as the FRFs). For mode shapes from test, this would typically be "Excitation Force". For mode shapes from analysis, this would typically be "Unknown" (i.e., unitless). This data type determines unit conversion during import and export.

The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
0	'Unknown'
1	'General'
2	'Stress'
3	'Strain'
5	'Temperature'
6	'Heat Flux'
8	'Displacement'
9	'Force'
11	'Velocity'
12	'Acceleration'
13	'Excitation Force'
15	'Pressure'
16	'Mass'
17	'Time'
18	'Frequency'
19	'RPM'
20	'Order'
21	'Sound Pressure'
22	'Sound Intensity'
23	'Sound Power'
24	'Cycles'
25	'Torque'
26	'Moment'
27	'LoadFactor'
28	'Gravitational Acceleration'
29	'Element Force'
30	'Element Moment'
31	'Signal'
32	'Unitless Scalar'
33	'Unitless Real'
34	'Unitless Integer'
35	'Voltage'
36	'Electric Current'

OrdDenExpForce

An integer value which defines the force exponents for the data type of the denominator of the shape. This needs to be specified explicitly only for the "General" OrdDenDataType. For all others, it is defined automatically. If this attribute is changed, the OrdDenDataType will be set to "General". During importing and exporting, the exponents are used to convert units.

OrdDenExpLength

An integer value which defines the length exponents for the data type of the denominator of the shape. This needs to be specified explicitly only for the "General" OrdDenDataType. For all others, it is defined automatically. If this attribute is changed, the OrdDenDataType will be set to "General". If OrdDenTypeQual is set to rotation, the length is assumed to be unitless and expressed in radians. During importing and exporting, the exponents are used to convert units.

OrdDenExpTemp

An integer value which defines the temperature exponents for the data type of the denominator of the shape. This needs to be specified explicitly only for the "General" OrdDenDataType. For all others, it is defined automatically. If this attribute is changed, the OrdDenDataType will be set to "General". The standard ordinate data types use the Kelvin or Rankine scale to express temperature. During importing and exporting, the exponents are used to convert units.

OrdDenExpTime

An integer value which defines the time exponents for the ordinate denominator data type. This is a "virtual" attribute, in that it is not actually stored in the object. It is a read-only attribute. The value returned is based on the data type. This attribute is not used for any units conversion.

OrdDenTypeQual

This attribute affects the interpretation of the ordinate numerator units exponents. This attribute is necessary for all OrdDenDataTypes except for "General". The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
0	'Translation'
1	'Rotation'

The difference in interpretation of the units exponent is in the length. For rotation, the length is unitless and assumed to be in radians.

OrdNumDataType

Defines the data type for the ordinate numerator of the frequency response functions from which the shape was defined (mode shapes are considered to be in the same units as the FRF's). For mode shapes from test, this would typically be "Acceleration", or other data type corresponding to the measurement. For mode shapes from analysis, this would typically be "Displacement". This data type determines unit conversion during import and export from I-deas.

The available data types and their corresponding numeric identifier are shown in the table under OrdDenDataType.

OrdNumExpForce

An integer value which defines the force exponents for the data type of the numerator of the shape. This needs to be specified explicitly only for the "General" OrdNumDataType. For all others, it is defined automatically. If this attribute is changed, the OrdNumDataType will be set to "General". During importing and exporting, the exponents are used to convert units.

OrdNumExpLength

An integer value which defines the length exponents for the data type of the numerator of the shape. This needs to be specified explicitly only for the "General" OrdNumDataType. For all others, it is defined automatically. If this attribute is changed, the OrdNumDataType will be set to "General". If OrdNumTypeQual is set to rotation, the length is assumed to be unitless and expressed in radians. During importing and exporting, the exponents are used to convert units.

OrdNumExpTemp

An integer value which defines the temperature exponents for the data type of the numerator of the shape. This needs to be specified explicitly only for the "General" OrdNumDataType. For all others, it is defined automatically. If this attribute is changed, the OrdNumDataType will be set to "General". The standard ordinate data types use the Kelvin or Rankine scale to express temperature. During importing and exporting, the exponents are used to convert units.

OrdNumExpTime

An integer value which defines the time exponents for the ordinate numerator data type. This is a "virtual" attribute, in that it is not actually stored in the object. It is a read-only attribute. The value returned is based on the data type. This attribute is not used for any units conversion.

OrdNumTypeQual

This attribute affects the interpretation of the ordinate numerator units exponents. This attribute is necessary for all OrdNumDataTypes except for "General". The available data types and their corresponding numeric identifier are shown in the table under OrdDenTypeQual.

OrdinateAxisLab

This is a character string of maximum length 20 that can be used to override the default Ordinate axis label. It is used only for operating deflection shapes.

OrdinateUnitsLab

This is a character string of maximum length 20 that can be used to override the default Ordinate units label. It is used only for operating deflection shapes.

OwnerName

Character string of length 16 which identifies the username of the person who created the shape.

ReferenceCoord

Character string of up to 14 characters which defines the reference coordinate that was used to scale the modal coefficients. It is a combination of ReferenceNode and ReferenceDir. Note that setting the ReferenceCoord changes the ReferenceNode and ReferenceDir, and vice versa.

The reference coordinate normally refers to the physical orientation of the exciter on a tested structure. This information is made up of a location number, direction, and sense. For example, a reference coordinate of '1X+' indicates a location of point number 1 on the structure, with a positive direction along the X axis.

ReferenceDir

String of up to 4 characters which identifies the direction and sense of the reference used to scale the mode shape. Any four characters may be used. ReferenceNode, combined with ReferenceDir, make up ReferenceCoord.

ReferenceNode

Integer value which specifies the node number of the reference used to scale the mode shape. Enter a zero if you do not want a value to appear in the attributes. ReferenceNode, combined with ReferenceDir, make up ReferenceCoord.

ResponseCoord

Character string of up to 14 characters which defines the response coordinate used to scale the modal coefficients. It is a combination of ResponseNode and ResponseDir. Note that setting the ResponseCoord changes the ResponseNode and ResponseDir, and vice versa.

The response coordinate normally refers to the physical orientation of a measured response to an input to the structure. This information is made up of a location number, direction, and sense. For example, a response coordinate of '2X+' indicates a location of point number 2 on the structure, with a positive direction along the X axis.

ResponseDir

String of up to 4 characters which identifies the direction and sense of the response used to scale the mode shape. Any four characters may be used. ResponseNode, combined with ResponseDir, make up ResponseCoord.

ResponseNode

Integer value which specifies the node number of the response used to scale the mode shape. Enter a zero if you do not want a value to appear in the attributes. ResponseNode, combined with ResponseDir, make up ResponseCoord.

Shape

Real or complex column vector of mode shape coefficients. The size of Shape should be NumberNodes times DOFType. All degrees of freedom for each node are stored together, and the ordering of the nodes matches the order of the Nodes attribute.

ShapeType

This attribute defines the mode shape type as either a real mode or complex mode. The shape type affects the interpretation of the modal mass and modal damping attributes. The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
1	'Real'
2	'Complex'

SolutionMethod

Documents the curve-fitting method that was used to generate the modal coefficients. The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
0	'User Defined'
1	'Move Response'
2	'Complex Exponential'
3	'Circle Fit'
4	'Polyreference'
5	'SDOF Polynomial'
6	'Direct Parameter'
14	'Orthogonal Polyreference'
15	'Frequency Polyreference'
20	'Structural Modification'
21	'COMAC'
22	'Mode Shape Math'
23	'Real Mode Approximation'
24	'Generic Move Response'

Shape Data Attributes