General > Aj_matrix

`Aj_matrix`

## Purpose

kinematic matrix of structural model with 2d/3d truss and 2d frame elements

## Synopsis

`Aj = Aj_matrix (Model)`

## Description

AJ_MATRIX kinematic matrix of structural model with 2d/3d truss and 2d frame elements AJ = AJ_MATRIX (MODEL) the function forms the kinematic matrix AJ for all degrees of freedom (DOFs) and all element deformations of the structural model specified in data structure MODEL; the kinematic matrix AJ includes the effect of joint offsets for the elements; the function is currently limited to 2d/3d truss and 2d frame elements

## Cross-Reference Information

This function calls:

- Localize returns the node coordinates and id array of element
- ElmLenOr element length and x-axis orientation (direction cosines)
- TranJnt sets up transformation matrix for finite size joints

- Event2Event_NLAnalysis event-to-event incremental analysis with linear or P-DELTA geometry
- PlasticAnalysis collapse load factor, basic forces, and collapse mechanism by plastic analysis
- Get_Veps determine the elastic deformations from the displacements and plastic deformations