This article introduces an R package, dietr, which calculates fractional trophic levels from quantitative diet item and qualitative food item data following the routine implemented in TrophLab within the open source R environment. dietr is easy to use and can quickly calculate trophic levels for many diet records. In addition to calculating trophic levels following the TrophLab routines, users can also specify a taxonomic hierarchy and estimate trophic levels at multiple taxonomic levels in a single call of a function. Additionally, dietr works well with FishBase data obtained in R using rfishbase and comes with pre-made databases of prey trophic levels that users can utilize for estimating trophic levels. dietr can also calculate several prey electivity indices. I provide information on dietr’s performance and provide a use case example of how dietr can be used on an empirical dataset. Trophic levels for hundreds of specimens can be calculated in a few seconds and the flexibility of dietr’s input allows users to easily calculate trophic levels from their own data.

中文翻译：

---

饮食者：用于从定量和定性饮食数据计算部分营养水平的 R 包

本文介绍了一个 R 包 Dietr，它按照在 TrophLab 中在开源 R 环境中实施的例程，根据定量饮食项目和定性食品项目数据计算分数营养水平。节食者易于使用，可以快速计算许多饮食记录的营养水平。除了按照 TrophLab 例程计算营养级别外，用户还可以指定分类层次结构并在单个函数调用中估计多个分类级别的营养级别。此外，dietr 可以很好地处理使用 rfishbase 在 R 中获得的 FishBase 数据，并附带预制的猎物营养级别数据库，用户可以利用这些数据库来估计营养级别。饮食者还可以计算几个猎物选择性指数。我提供了有关 Dietr 性能的信息，并提供了一个用例示例，说明如何在经验数据集上使用 Dietr。可以在几秒钟内计算出数百个标本的营养水平，并且节食者输入的灵活性允许用户根据自己的数据轻松计算营养水平。