A literate process for the certification of scientific and engineering software

我们的主要目标是开发可认证的科学和工程软件。当前过程的一个问题是软件工件之间存在相当多的重复，以及这些工件之间明确缺乏可追溯性。我们相信，我们可以通过采纳文学编程（LP）背后的思想来解决这两个问题，在LP中，程序的编写首先以人类读者可以理解为目标，而不是人为地受到传统计算机代码所需的顺序和格式的限制。****在经典LP中，从读写源文件中提取两个项目：用户可读的文档和计算机可读的源代码。我们提出的文字过程将扩展这个想法，这样“源”文件就可以以多种方式进行处理，不仅可以提取代码及其解释，还可以提取需求说明、应用程序编程接口（API）、测试用例、测试报告和构建指令。这将允许我们在所有这些软件工件之间共享相当数量的公共信息，从而减少重复。同时，由于共享信息将被提取到正确的工件中，因此可追溯性得到了提高。****为了开发、激励和记录识字过程，我们将使用一个关于一组常微分方程（ODE）解算器代码生成的案例研究。在族方法中，代码的生成考虑了族中的共性，但根据其可变性区分每个成员。代码生成方法促进了认证组件的重用，从而实现了快速认证。ODE求解器家族将放在核安全分析的背景下。特别地，将开发一个例子来解决作为核反应堆燃料销热分析一部分的ode系统。

Our principal objective is to develop certifiable scientific and engineering software. One problem with current processes is that there is considerable duplication between software artifacts, as well as a definite lack of traceability between these artifacts. We believe that we can solve both of these problems by adapting the ideas behind Literate Programming (LP), in which programs are written first with the goal of being understandable to human readers, rather than being artificially constrained by the ordering and formatting required by conventional computer code.****In classical LP, from literate source files two items are extracted: the user readable documentation and the computer readable source code. Our proposed literate process will extend this idea so that "source" files can be processed in multiple ways to extract not just the code and its explanation, but also the requirements specification, the Application Program Interface (API), the test cases, the test report and the build instructions. This will allow us to share the considerable amount of information in common between all these software artifacts, thus decreasing duplication. At the same time traceability is increased, since this shared information will be extracted into the correct artifacts.****To develop, motivate and document the literate process we will use a case study of code generation for a family of ordinary differential equation (ODE) solvers. In the family approach code is generated taking into account the commonalities in the family, but distinguishing each member based on its variabilities. The code generation approach facilitates reuse of certified components, leading to quick certification. The family of ODE solvers will be put in the context of nuclear safety analysis. In particular, an example will be developed that solves a system of ODEs as part of the thermal analysis of fuel pins in a nuclear reactor.