No comment... I am quite unphotogenic...

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Christoph Quirin Lauter

Assistant professor at University of Alaska Anchorage (UAA).

Maître de conférences habilité en disponiblité in the PEQUAN project at the LIP6 lab of Sorbonne University.

Before that, Software Engineer for Intel Corporation, member of the Numerics team.

Former Ph.D. student under Florent de Dinechin, in the Arénaire project, at LIP.

Married, one little daughter, one little son.

Research interests:

The subject of my Ph.D. thesis has been the correct rounding of elementary functions, such as exp(x), log(x), sin(x), asin(x), power(x,y), in IEEE 754 double precision.

The implementation of elementary functions faces several difficulties of different kind:

I participated on the revision of the IEEE 754 standard that reigns floating-point arithmetic. With Florent de Dinechin and Jean-Michel Muller, I proposed the following reformulation of the chapter on elementary functions. The proposal can be found here. A second remark on the draft version 1.6.0 of january 10, 2008 can be found here.

I have done research on how the implementation and certification of a mathematical function can be automatized. Starting from this, I have been interested on safe algorithms for some high-level computation problems. As an example, let me mention the computation of the infinity norm of a composite function. Here, computation means giving an under- and, more important, an over-estimate of the unknown supremum of the function. The function itself is given as an expression tree. Its leaves are basic functions or "black-box" codes. Of course, the multi-precision evaluation of such a tree in a point or small interval is an important sub-problem. This yields directly to questions on how intermediate precision must be adapted for ensuring a faithful rounding...

I have integrated those algorithms in the software tool Sollya. Sollya is intended as a safe support for the development of elementary functions. I used then Sollya for my Metalibm project, striving to an automatic implementer for mathematical (libm) functions.

In the recent years, for my research published e.g. with my Habilitation à Diriger des Recherches, I investigated means to implement and, in particular, extend the typical IEEE754 floating-point environment with respect to several dimensions, such as:

Short curriculum vitae:

Ph.D. students and interns I work with or I used to work with:


Articles in international journals:

Articles in the proceedings of international conferences:

Research reports:

Master's, Ph.D. thesis, Habilitation (HDR) thesis:

Presentations and Workshops:


Developed open source software:



Address: University of Alaska Anchorage
Christoph Lauter
3211 Providence Dr
Anchorage, AK, 99508-4614
Phone: +1 907 786 0619
+33 1 82 52 17 77
+1 907 891 6834
+1 907 519 0505
+49 9621 7781170
CNET: +1 328 5073

Phone Collection:

As a hobby, I collect old telephone sets and the technology that goes with that. Some information can be found on this page.

Last update: 02/11/2022.