Re: Octave criterion for matrix singularity

[Carlo De Falco]

> On 26 Feb 2019, at 14:21, mabalenk <address@hidden> wrote:
> 
> Yes, it does help. Thank you. But I don't understand, where is the division
> by 2 hidden. It seems to me, that rcond is compared to eps, the machine
> precision.

Try by yourself :

>> eps
ans =    2.2204e-16
>> 1 + eps(1) == 1
ans = 0
>> 1 + eps(1)/2 == 1
ans = 1

or read the manual :

>> help eps

....

     More precisely, 'eps' is the relative spacing between any two
     adjacent numbers in the machine's floating point system.  This
     number is obviously system dependent.  On machines that support
     IEEE floating point arithmetic, 'eps' is approximately 2.2204e-16
     for double precision and 1.1921e-07 for single precision.

....

HTH,
c.