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 From: Jonathan Camilleri Subject: Date: Fri, 23 Oct 2015 16:00:55 +0200

GNU Octave, version 4.0.0
Copyright (C) 2015 John W. Eaton and others.
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Octave was configured for "i686-w64-mingw32".

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Read http://www.octave.org/bugs.html to learn how to submit bug reports.
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>> A=[1,2,1,1,212,1000]
A =

1      2      1      1    212   1000

>> B= rand(3,2)
B =

0.58139   0.52678
0.60398   0.34393
0.49790   0.32606

>> C=1(3,2)
error: A(I,J): row index out of bounds; value 3 out of bound 1
>> C=0.9(3,2)
error: A(I,J): row index out of bounds; value 3 out of bound 1
>> C=(3,2)
parse error:

syntax error

>>> C=(3,2)
^

>> 2 * A
ans =

2      4      2      2    424   2000

>> 4.5 * A
ans =

4.5000      9.0000      4.5000      4.5000    954.0000   4500.0000

>> 0.6944 * A ^ 0.5
error: for A^b, A must be a square matrix. Use .^ for elementwise power.
>> 0.6944 * A
ans =

0.69440     1.38880     0.69440     0.69440   147.21280   694.40000

>>
>> x = A \ b
error: 'b' undefined near line 1 column 9
>>
>> x = A \ b
error: 'b' undefined near line 1 column 9
>> x = A \ B
error: operator \: nonconformant arguments (op1 is 1x6, op2 is 3x2)
>> a = rand(3,3)
a =

0.824214   0.029893   0.542378
0.668594   0.111037   0.547211
0.499944   0.341851   0.948776

>> b = rand(3,4)
b =

0.26867   0.98889   0.48521   0.44561
0.45460   0.20859   0.44251   0.30262
0.38680   0.32572   0.91684   0.82033

>> x = b \ a
x =

1.3559534  -0.0752192   0.4586538
0.5842781  -0.1827420   0.0082588
0.0916040   0.2354118   0.5122098
-0.3642875   0.2616426   0.3645640

>>

I cannot figure out how matrix division is working out
i.e. 0.26867 divided by 1 / 0.82414 not equal to 1.3559534

1. Maths Is Fun
2. Gnu.org Octave documentation/tutorial

--
Jonathan Camilleri

Mobile (MT): ++356 7982 7113