MasterAllRound: the PC calculator

Matrices: example inverse matrix: flexibility matrix

This example is from the area of finite element analysis. The task is to get the flexibility matrix [F]. The flexibility matrix is the inverse matrix of the stiffness matrix [K]. The example shows only a 3x3 matrix but there is no size restriction for MasterAllRound.

Let's assume the following stiffness matrix:
Steifigkeitsmatrix

To solve this problem, more than one input method exists in MasterAllRound. We will show you the solution using number symbols (constants).

Using the smart calculator of MasterAllRound, we declare the values of the number symbols K11, K12 et cetera first:

K11 = 171.0 and   K12 = -162.2 and   K13 = 66.6

K21 = K12 and   K22 = 235.0 and   K23 = -162.2

K31 = K13 and   K32 = K23 and   K33 = 171.0
After this, we enter the size of the matrix (n=3)
We will represent the cells with the number symbols K11, K12 et cetera
We start the calculation of the inverse matrix by clicking on the "Invert matrix A" button

The result is: Flexibility matrix

Here you see the MasterAllRound window with the input and the result matrix: Matrix inversion: input and result

(To matrices) (To MAR Plus)