R help - Dec 2009 - matrix data appears corrupted.. appears to be pairs of decimal numbers glommed together

Hello,

We are occasionally getting matrix results that appear to be corrupted... here
are the last several rows of an example, copy-pasted out of the R command
window.  These are supposed to be floating point numbers.

[25015,]  1.820848e-01-3.2090e-06i
[25016,]  2.178046e-01-4.8140e-06i
[25017,]  1.820848e-01-3.2090e-06i
[25018,]  1.820848e-01-3.2090e-06i
[25019,]  1.144594e-01-1.6657e-06i
[25020,]  1.820848e-01-3.2090e-06i
[25021,] -1.293271e-01+4.3889e-06i
[25022,]  1.144594e-01-1.6657e-06i
[25023,]  1.820848e-01-3.2090e-06i
[25024,]  1.820848e-01-3.2090e-06i
[25025,]  1.173487e-01-4.4415e-07i
[25026,]  1.820848e-01-3.2090e-06i
[25027,]  1.375304e-01-3.6167e-06i
[25028,]  1.820848e-01-3.2090e-06i
[25029,] -1.293271e-01+4.3889e-06i
[25030,]  1.820848e-01-3.2090e-06i
[25031,]  1.820848e-01-3.2090e-06i
[25032,]  1.820848e-01-3.2090e-06i
[25033,]  1.820848e-01-3.2090e-06i

Any general idea what may be going on here?

It is a sporadic problem... it occurs maybe 2% or 3% of the time when running
this particular script on various data.

I apologize for not including a pared-down example that reproduces the
problem.... we are using an R script written elsewhere on large data sets.  If
someone wants more specifics please follow up.

Steve Grubb

On Dec 3, 2009, at 3:02 PM, Stephen Grubb wrote:
> Hello,
>
> We are occasionally getting matrix results that appear to be  
> corrupted... here are the last several rows of an example, copy- 
> pasted out of the R command window.  These are supposed to be  
> floating point numbers.
>
> [25015,]  1.820848e-01-3.2090e-06i
> [25016,]  2.178046e-01-4.8140e-06i
> [25017,]  1.820848e-01-3.2090e-06i
> [25018,]  1.820848e-01-3.2090e-06i
> [25019,]  1.144594e-01-1.6657e-06i
> [25020,]  1.820848e-01-3.2090e-06i
> [25021,] -1.293271e-01+4.3889e-06i
> [25022,]  1.144594e-01-1.6657e-06i
> [25023,]  1.820848e-01-3.2090e-06i
> [25024,]  1.820848e-01-3.2090e-06i
> [25025,]  1.173487e-01-4.4415e-07i
> [25026,]  1.820848e-01-3.2090e-06i
> [25027,]  1.375304e-01-3.6167e-06i
> [25028,]  1.820848e-01-3.2090e-06i
> [25029,] -1.293271e-01+4.3889e-06i
> [25030,]  1.820848e-01-3.2090e-06i
> [25031,]  1.820848e-01-3.2090e-06i
> [25032,]  1.820848e-01-3.2090e-06i
> [25033,]  1.820848e-01-3.2090e-06i
>
> Any general idea what may be going on here?
Those are all complex numbers.
>
> It is a sporadic problem... it occurs maybe 2% or 3% of the time  
> when running this particular script on various data.
You are most likely "solving" or inverting <something> that does
not
have all real roots or eigenvalues  ... or something.
>
> I apologize for not including a pared-down example that reproduces  
> the problem.... we are using an R script written elsewhere on large  
> data sets.  If someone wants more specifics please follow up.
>
> Steve Grubb

David Winsemius, MD
Heritage Laboratories
West Hartford, CT