Southampton BASIC System: Difference between revisions

Revision as of 09:31, 23 May 2009

Revision as of 00:46, 24 May 2009

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=== Arrays ===

Support for handling arrays of data was relatively strong, with <code>MAT</code> statements able to read an entire array from <code>DATA</code> statements, and perform useful [[matrix (mathematics)|matrix]] operations such as adding[[matrix oraddition]], multiplying two[[matrix matricessubtraction]], or[[matrix evenmultiplication]], and finding the [[multiplicative inverse matrix]] offor a [[square matrix]].

Example:

10 DATADIM 0A(3,0,1,0,1,0,1,0,03)

20 DIMMAT READ A(3,3)

30 DATA 1,1,2,1,0,2,0,2,1

30 MAT READ A

40 DATADIM 2,4B(3,3,-1,0,-2,1,-4,5)

50 DIMMAT READ B(3,3)

60 DATA 0,0,1,0,1,0,1,0,0

60 MAT READ B

70 DIM C(3,3),D(3,3)

80 MAT C = A * B

90 MAT PRINT D=INV(C,)

30100 MAT READPRINT AD,

A contains

<math>\begin{pmatrix}

{|

|<code>A</code> is read from the first <code>DATA</code> statement

|<math>\begin{pmatrix}

1 & -41 & 52 \\

21 & 40 & 32 \\

0 & 2 & 1

\end{pmatrix}</math>

|-

|<code>B</code> is read from the second <code>DATA</code> statement

|<math>\begin{pmatrix}

0 & 0 & 1 \\

0 & 1 & 0 \\

1 & 0 & 0

\end{pmatrix}</math>

|-

, B contains

|<code>C</code> is calculated by multiplying <code>A</code> and <code>B</code>

<math>\begin{pmatrix}

|<math>\begin{pmatrix}

2 & 4 & 3 \\

-12 & 01 & -21 \\

12 & -40 & 51 \\

1 & 2 & 0

\end{pmatrix}</math>

|-

, C contains

|<code>D</code> is calculated as the inverse of <code>C</code>

<math>\begin{pmatrix}

|<math>\begin{pmatrix}

1 & -4 & 5 \\

-12 & 02 & -21 \\

21 & 4-1 & 30 \\

4 & -3 & -2

\end{pmatrix}</math>

|}

The output would be

This is the output:

12 -4 5 2 1

-1 0 -21 0

24 4 -3 -2

== Debugging ==