|Re: [eigen] Reusing a sparse matrix for SparseLU|
[ Thread Index |
| More lists.tuxfamily.org/eigen Archives
- To: eigen <eigen@xxxxxxxxxxxxxxxxxxx>
- Subject: Re: [eigen] Reusing a sparse matrix for SparseLU
- From: Gael Guennebaud <gael.guennebaud@xxxxxxxxx>
- Date: Mon, 3 Dec 2018 15:37:26 +0100
- Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=0wUxhgSG3FstFoRV1K/dVlQk3tpk0v+X94jE6/tbQkM=; b=J75o7Se+9Ow6GtJs5tUrSqDvsQt+ENwcyFiTqTzwVvRVk+XGd2KXmMHze/1wtNb/uc YxVt0wsbh9syXla9JSa8Us60BySGlfEHrARq1f75Tr5jRmUZoV6CHCQyj16lRzwZhRcl Fiy6puH9JB8+CwP+whGb3V9PjppDYpe+BmzxiQBJw0w+e6Bw8lfItYMfuHAhjgUyFB// 0M1wMNlHUYqO+FnRD1Et3gOPQOnazrYaSEYdjMLPmkK400nfGRf5ZHOMXZC9fEmMj4IZ 7/tYMPkmSG7JvjBBNIc02MBHMXxKMKaZtMiIDmTSgnnJtw2NIhKUF3mw7CYn7E/3iFbm +ozg==
hm... if you're thinking about using coeffs() << v0, v1, v2... then your matrix is likely very small. What is its typical size and number of non-zeros? If too small and not sparse enough better use a dense matrix/solver.
Matthieu Brucher writes:
> Hi Alberto,
> Thanks for the answer. Unfortunately, this still makes me create
> another array,
I need to create an array for the coifs, don't I? Seems like I could use valuePtr as well.
But the speed is very bad and profiles indicate that there may be mallocs inside the factorisation or the solve :/
> I'd rather populate the elements directly.
You can do precisely that, by using the coeffs() vector.
Oh, you mean I could do coeffs() << v0, v1, v2...?