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I'm using the igraph package in R to run PageRank. I ran it for my graph and got this error:

At arpack.c:1130 : ARPACK error, The Schur form computed by LAPACK routine dlahqr could not be reordered by LAPACK routine dtrsen.

I read online that this could be caused by your graph having multiple disjoint components. So I ran

gList = decompose.graph(g)
is.connected(gList[[20]])  # evaluates to true

But I'm still getting this same error when I run

page.rank(gList[[20]])

What could be causing this? Is there any way to get more info about the error?

(This only happens for some graphs and not others. The problematic graph has 35k vertices, but I can attempt to upload some relevant data if it helps.)

Xodarap
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    This error message got us (i.e. the developers of igraph) stumped quite a few times by now and we still don't know what causes it. Send me a small test graph via email and I'll try to take a look at it. – Tamás Feb 24 '13 at 21:06

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