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From: Rhys Ulerich <rhys.ulerich@gmail.com>
To: Patrick Alken <patrick.alken@colorado.edu>
Cc: "gsl-discuss@sourceware.org" <gsl-discuss@sourceware.org>
Subject: Re: increment a single element of matrix/vector
Date: Tue, 28 Jan 2014 02:08:00 -0000	[thread overview]
Message-ID: <CAKDqugSbjFausECoC3Bm_JdYtOK9VwuG_nkOKtqk4A_e+Cb0Bw@mail.gmail.com> (raw)
In-Reply-To: <52E6EFF3.1000808@colorado.edu>

> I was thinking of adding two routines to GSL, to increment a single element
> of a matrix or vector by some amount, since I'm always doing things like:
>
> gsl_vector_set(v, i, gsl_vector_get(v, i) + x);
>
> which I think is ugly and annoying....

Agreed.  This has often bugged me.

> Or also is there another solution to this problem that I don't know about?

How about using

INLINE_DECL double * gsl_vector_ptr (gsl_vector * v, const size_t i);

to say *gsl_vector_ptr(v, i) += x ?  Never knew about this until I
just went fishing for it.

- Rhys

  reply	other threads:[~2014-01-28  2:08 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-01-27 23:47 Patrick Alken
2014-01-28  2:08 ` Rhys Ulerich [this message]
2014-01-28  2:15   ` Rhys Ulerich
2014-01-28  3:06     ` Patrick Alken
2014-01-28 20:45       ` Patrick Alken
2014-01-28 21:16         ` Rhys Ulerich
2014-01-28 21:26           ` Patrick Alken

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