Miscellaneous Functions for Environmental Analyses

**envalysis** is an R package containing miscellaneous functions for data analysis in environmental chemistry and ecotoxicology. Provides, for example, `calibration()`

to calculate calibration curves and corresponding limits of detection (LODs) and limits of quantification (LOQs) according to German DIN 32645 (2008). `texture()`

makes it easy to estimate soil particle size distributions from hydrometer measurements (ASTM D422-63, 2007). Some functions of the package require **ggplot2** or **drc**.

## Functions

The following functions are available:

### Data manipulation and analysis

- Calculating limits of detection
`lod()`

and limits of quantification`loq()`

as part of the`'calibration'`

class to produce linear calibration curves in accordance with German DIN 32645 (2008); see vignette for details - Calculating concentrations from calibration curves using
`inv_predict()`

- Finding optimum weights for weighted calibrations using
`weight_select()`

- Estimating matrix effects (signal suppression/enhancement) with
`matrix_effect()`

- Determining particle size distributions and soil texture classes (DIN/USDA) measured with a soil hydrometer in accordance with ASTM D422-63 (2007) using
`texture()`

; see vignette for details - Confidence intervals
`CI()`

, standard errors`se()`

, and root mean square errors`rmse()`

- Various sorption isotherms
`sorption()`

### Data presentation

- Categorize water drop penetration times according to Bisdom et al. (1993) with
`bisdom()`

- Report significant figures, namely round means and errors to the least significant digit, using
`signifig()`

- Clean, black-and-white ggplot2 theme for scientific publications
`theme_publish()`

; a preview is available here

## Installation

**envalysis** is available on CRAN and GitHub.

### Install from CRAN (stable version)

You can install the released version of **envalysis** from CRAN with:

`install.packages("envalysis")`

### Install from GitHub (development version)

To install the development version of this package, paste the following code into your R console (requires **devtools**):

```
if(!require(devtools)) install.packages("devtools")
devtools::install_github("zsteinmetz/envalysis")
```