Re: [igraph] Bonpower Crashes (Sparse matrix Help)

[Gábor Csárdi]

Hello Nathan,

On Wed, Apr 8, 2009 at 1:07 AM, Surendar Swaminathan
<address@hidden> wrote:
[...]
> Error
>
> Error in solve(id - exponent * d, tol = tol) :
>   INTEGER() can only be applied to a 'integer', not a 'NULL'

This is not a crash, it is an error message. Maybe it does not matter
for you, but it does matter if one wants to find the bug. It seems to
be a problem in the Matrix package, for me it fails in various ways.
E.g. if I simplify() the first graph and keep only the giant component
of it, then I get:

Error in solve(id - exponent * d, tol = tol) :
  cs_lu(A) failed: near-singular A (or out of memory)

which is fine, it just says that the equation cannot be solved. But
for some graphs I also get

> bp <- bonpow.sparse(g2, exponent=0.9)
Error in solve(id - exponent * d, tol = tol) :
  INTEGER() can only be applied to a 'integer', not a 'builtin'

and sometimes it really crashes:

> bp <- bonpow.sparse(g2, exponent=0.9)
*** glibc detected *** corrupted double-linked list: 0x0000000003188ae0 ***

This is on Linux and R 2.8.1.

Anyway, this is an issue with 'solve' from the 'Matrix' package. Try
to post to R-help, send the bonpow.sparse code and the links to your
graphs. Your subject line should be something like "Matrix package,
solve() errors and crashes". Make sure you also send the output of the
sessionInfo() command.

Best,
G.

[...]
> Error
> Error: cannot allocate vector of size 3.3 Gb
> In addition: Warning messages:
> 1: In solve(id - exponent * d, tol = tol) :
>   Reached total allocation of 1535Mb: see help(memory.size)
> 2: In solve(id - exponent * d, tol = tol) :
>   Reached total allocation of 1535Mb: see help(memory.size)
> 3: In solve(id - exponent * d, tol = tol) :
>   Reached total allocation of 1535Mb: see help(memory.size)
> 4: In solve(id - exponent * d, tol = tol) :
>   Reached total allocation of 1535Mb: see help(memory.size)

This is a memory issue. Maybe see ?Memory, but I don't it would ever
work on 32bit Windows XP.

[...]

-- 
Gabor Csardi <address@hidden>     UNIL DGM