# Manuals/calci/TRIDIAGONAL

MATRIX("TRIDIAGONAL",order)

• is the size of the Tridiagonal matrix.

## Description

• This function returns the matrix with the property of tridiagonal.
• A square matrix with nonzero elements only on the diagonal and slots horizontally or vertically adjacent the diagonal.
• i.e., along the subdiagonal and superdiagonal.
• So a tridiagonal matrix is a matrix that has nonzero elements only on the main diagonal, the first diagonal below this, and the first diagonal above the main diagonal.
• A tridiagonal is of the form:

• A general tridiagonal matrix is not necessarily symmetric or Hermitian,but tridiagonal matrix is a matrix that is both upper and lower Hessenberg matrix.
• In Calci, MATRIX("tridiagonal") gives the tridiagonal matirx of order 3.
• Users can change the order of the matrix.

## Examples

• MATRIX("tridiagonal") =18
• MATRIX("tridiagonal",3)
 59 58 0 -93 3 21 0 -24 90
• MATRIX("tridiagonal",6)
 23 9 0 0 0 0 -6 91 -75 0 0 0 0 32 -25 -11 0 0 0 0 -44 42 -1 0 0 0 0 61 -26 86 0 0 0 0 -50 -92

## Related Videos

Tridiagonal Matix