Scientific Unit Testing Dave Steffen, Ph.D. Software Lead in Physics which is relevant dsteffen@scitec.com www.scitec.com 1If I have seen further than others, it is by standing upon the shoulders Limit tests to the code in question 26Reproducibility (handling nondeterministic results) Most scientific experiments have measurement error or noise. Interference from the environment: noisy signals correct Unit tests attempt to show !C Confidence in C tracks thoroughness of tests A.K.A "The Scientific Method" 42Acknowledgements Kris Jusiak, Quantlab Financial Check out his C++20 macro-free unit

Poster submission: Modern C++ for Parallelism in High Performance Computing Victor Eijkhout CppCon 2024 Introduction This poster reports on ‘D2D’, a benchmark that explores elegance of expression and and perfor- mance in the context of a High Performance Computing ‘mini-application’. The same code has been implemented using a number of different approaches to parallelism. Implementations are discussed discussed with performance results. Relevance C++ is making inroads into HPC / Scientific Computing, a field traditionally dominated by C and Fortran. With all the developments in modern C++ such as range

Constraints Architecture Substitution Construction Conclusion Symbolic Calculus for High-Performance Computing from Scratch using C++23 Vincent Reverdy Laboratoire d’Annecy de Physique des Particules, France Symbolic Computation, Joël Falcou and Vincent Reverdy, CppCon 2019 Hypothesis This is the Scientific Computing Track so you all know about optimization, performance, parallelism, . . . What this talk is not about Complicated maths (you are smart people, you can do it yourself) High-performance computing (you all know about it + see the 2019 talk for that) Benchmarks, assembly, and optimization (see

from developing across multiple architectures ▪ Develop with open standards for accelerator computing ▪ Standards and industry defined libraries For Software Developers For Processor Developers ▪ optimized toolchain Free and based on open standards“this work supports the productivity of scientific application developers and users through performance portability of applications between Aurora nliber@anl.govWHO AM I? ▪ Argonne National Laboratory ▪ Computer Scientist ▪ Argonne Leadership Computing Facility ▪ C++, SYCL, Kokkos ▪ Aurora ▪ WG21 - ISO C++ Committee ▪ Vice Chair, Library Evolution

and electronic components (SOTIF) ● Chair of UL4600 Object Tracking ● RISC-V Datacenter/Cloud Computing Chair ● http://wongmichael.com/about ● C++11 book in Chinese: https://www.amazon.cn/dp/B00ETOV2OQ powerful supercomputers in the world 34 Nevin “:-)” Liber nliber@anl.gov ● Advanced Leadership Computing Facility (ALCF) ○ Computer Scientist ○ Kokkos (SYCL/DPC++ backend) ○ Vice Chair WG21 Library Former host WG21 (C++) & WG14 (C) meetings This presentation was supported by the Exascale Computing Project (17-SC-20-SC), a collaborative effort of two U.S. Department of Energy organizations

DedicationIntroduction Firsts steps Context Theoretical foundations Outline of an implementation Conclusion Computing the evolution of the Universe 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 11.00 12 the implementation of this kind of expression templates: Symbolic Calculus for High-Performance Computing from Scratch using C++23, V. Reverdy, CppCon2023 CppCon - Vincent Reverdy - September 20th, 2024 Outlooks Toward a computer algebra system for C++ By combining last year strategies for symbolic computing and ode solvers so that we can have a nice syntax: solve [{ gpu }]( derivative (y, t) = a ∗ H0

Kitware Overview / Built on open source Computer Vision Data and Analytics Scientific Computing Medical Computing Software Solutions6 Where did CMake come from? • Kitware was the lead engineering

Lectured internationally as a software consultant and commercial trainer. � Retired from the Scientific Computing Division at Fermilab, specializing in C++ programming and in-house consulting. • Not dead 10 Copyright © 2020 by W alter E. Brown. All rights reserved. The following narration is by computing pioneer and Turing Award recipient Sir Maurice Wilkes (1913−2010) 10 So how do we program

https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p0009r9.html Damien Lebrun-Grandie Scientific Computing Track Chairgithub.com/griswaldbrooks/spanny2 motivations don’t we already have multidimensional .begin(), unique_vertices.end()}; }() computing unique coordinates at construction storing them as state 67github.com/griswaldbrooks/spanny2 layout_vertices

Lectured internationally as a software consultant and commercial trainer. � Retired from the Scientific Computing Division at Fermilab, specializing in C++ programming and in-house consulting. • Not dead