In flood frequency analysis (FFA), choices of distribution and methods can hinder the reproducibility of results. Besides, changes in climate, land use/cover, and water management can induce nonstationarity. Frameworks to select between stationary FFA (S-FFA) and nonstationary FFA (NS-FFA) are lacking, and NS-FFA tools are limited. Therefore, this paper introduces a systematic and software-supported framework enabling repeatable workflows for both S-FFA and NS-FFA. The framework has three modules to a) process flood series for exploratory data analysis (EDA) and NS-FFA model determination (if needed), b) select the S-FFA or NS-FFA approach underpinned by the EDA, and c) perform FFA including model determination, parameter estimation, uncertainty quantification, and model performance assessment. The framework incorporates various distributions, methods, and metrics, and recent advancements in NS-FFA for model determination and uncertainty quantification and allows for the modeller's intervention while ensuring reproducibility. The software is freely available to the public.

在洪水频率分析 (FFA) 中，分布和方法的选择可能会影响结果的再现性。此外，气候、土地利用/覆盖和水管理的变化也会导致非平稳性。缺乏在固定 FFA (S-FFA) 和非固定 FFA (NS-FFA) 之间进行选择的框架，并且 NS-FFA 工具也有限。因此，本文介绍了一个系统的、软件支持的框架，支持 S-FFA 和 NS-FFA 的可重复工作流程。该框架具有三个模块：a) 处理洪水系列以进行探索性数据分析 (EDA) 和 NS-FFA 模型确定（如果需要）；b) 选择以 EDA 为基础的 S-FFA 或 NS-FFA 方法；c) 执行FFA包括模型确定、参数估计、不确定性量化和模型性能评估。该框架结合了各种分布、方法和指标，以及 NS-FFA 的最新进展，用于模型确定和不确定性量化，并允许建模者进行干预，同时确保可重复性。该软件免费向公众开放。