The program is:

! Practice Program 8.1

! A matrix is a one-dimensional or two-dimensional array of numbers.

! A square matrix has the same number of rows and columns. The

! principal diagonal of a square matrix goes from the upper left

! corner to the lower right corner. The identity matrix is a square

! matrix with elements along the principle diagonal having a value

! of 1, and the other elements having a value of 0. Here is an

! identity matrix displayed by a True Basic program:

! 1 0 0 0

! 0 1 0 0

! 0 0 1 0

! 0 0 0 1

!

! Using FOR statements, create and display an identity matrix

! with 10 rows and columns (a 10-by-10 matrix).

! Pseudocode:

! 1. Name the matrix Identity (i,j)

! 2. Initiallize with zeros for all i,j; 1 to 10 for each

! 3. Print out the matrix elements

! 4. Now substitute 1's for zeros i=j and for 1-10 using FOR statements

! 5. Print out the new matrix

! 6. Consider using a subroutine to do this for any i=j=n.

! 7. Start with a 3x3 identity matrix in MEX8.1.2

! Review 8.4 Arrays with two dimensions on p 216

! Declare a 2-D 10x10 array with DIM Identity (1 to 10, 1 to 10)

! See EP8-7 p218 for a nested for loop method to initialize Identity (10,10)

DIM Identity (1 to 10, 1 to 10)

FOR row = 1 to 10

FOR column = 1 to 10

IF row = column then

LET Identity (row,column)=1

ELSE

LET Identity (row,column)=0

END IF

NEXT column

NEXT row

PRINT

FOR row = 1 to 10

FOR column = 1 to 10

SET COLOR "red"

PRINT Identity (row,column);

NEXT column

PRINT

NEXT row

SET COLOR "blue"

PRINT "This is a 10x10 identity matrix"

PAUSE 6

SOUND 500,0.2

END

The output is:

1 0 0 0 0 0 0 0 0 0

0 1 0 0 0 0 0 0 0 0

0 0 1 0 0 0 0 0 0 0

0 0 0 1 0 0 0 0 0 0

0 0 0 0 1 0 0 0 0 0

0 0 0 0 0 1 0 0 0 0

0 0 0 0 0 0 1 0 0 0

0 0 0 0 0 0 0 1 0 0

0 0 0 0 0 0 0 0 1 0

0 0 0 0 0 0 0 0 0 1

This is a 10x10 identity matrix