# envalysis

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")
```