--- title: "A photo key to Montana's broadleaf trees" output: rmarkdown::html_vignette vignette: > %\VignetteIndexEntry{A photo key to Montana's broadleaf trees} %\VignetteEngine{knitr::rmarkdown} %\VignetteEncoding{UTF-8} --- ```{r, include = FALSE} knitr::opts_chunk$set(collapse = TRUE, comment = "#>") ``` Montana has eleven native broadleaf (hardwood) trees, from the box elders and green ash of the eastern river bottoms to the aspen groves and paper birches of the mountains. This vignette shows a dichotomous key to them, written as a plain spreadsheet with a folder of photos, and the two ways dimoose can show it: a printable diagram and an interactive wizard. ## Make your own key in three steps The key is an ordinary CSV file, so the quickest way to write a key of your own is to start from a copy of it: 1. **Copy the template.** It ships with dimoose, next to its photos: ```{r, eval = FALSE} template <- system.file("extdata", "montana", package = "dimoose") dir.create("~/my-key") file.copy(template, "~/my-key", recursive = TRUE) # makes ~/my-key/montana/ ``` 2. **Edit it in Excel, Numbers or Google Sheets.** One row per lead: | Column | What goes in it | |---|---| | `Couplet` | The couplet's number. | | `Choice` | Optional: `a`, `b`, ...; left blank, the leads are lettered in order. | | `Question` | Optional: what the couplet asks, such as "Leaf type?". | | `Description` | What the lead says. | | `Goes to` | The next couplet, or blank when the lead names a species. | | `Species` | The result, written "Common name (Genus species)". | | `Photo` | Optional: photo file names in the same folder, separated by `;`. | Put your photos in the same folder and save the sheet as CSV. 3. **Build the key and look at it:** ```{r, eval = FALSE} library(dimoose) k <- keyFromSpreadsheet("~/my-key/montana/montana-key.csv", desc = "My key") k$validate() # lists any couplet that is never reached, etc. keyDiagram(k, "my-key.svg") # a printable diagram exportWizard(k, "my-key.html") # an interactive key for phones and browsers ``` If a row points to a couplet that is not in the sheet, or names a photo that is not in the folder, `keyFromSpreadsheet()` says which spreadsheet row to fix. To check the species names too, add `checkNames = TRUE`. dimoose then looks each scientific name up in the [GBIF](https://www.gbif.org) backbone taxonomy (this needs an internet connection) and warns about names that are misspelled, are outdated synonyms, or are not known at all, again by row. The Montana names all pass; a sheet with two mistakes would give: ```{r, eval = FALSE} k <- keyFromSpreadsheet("~/my-key/montana/montana-key.csv", checkNames = TRUE) #> Warning: Some species names do not match GBIF: #> Row 5: Fraxinus pensylvanica is not in GBIF; did you mean Fraxinus pennsylvanica? #> Row 9: Ulmus fulva is a synonym; GBIF accepts Ulmus rubra ``` `checkNames(k)` gives the same check as a table. ## The Montana key ```{r} library(dimoose) k <- montanaKey() k ``` `montanaKey()` is `keyFromSpreadsheet()` applied to the template above. Its first rows: ```{r} csv <- system.file("extdata", "montana", "montana-key.csv", package = "dimoose") head(read.csv(csv, check.names = FALSE), 4) ``` Every species was checked as native to Montana in the [Montana Field Guide](https://fieldguide.mt.gov) and [USDA PLANTS](https://plants.usda.gov). Common hackberry is left out because the Montana Field Guide gives its origin in the state as undetermined, and American elm because it is planted rather than native. The characters in each couplet come from the Montana Field Guide's descriptions and, for leaf stalks and buds, the [Virginia Tech Dendrology](https://dendro.cnre.vt.edu) fact sheets; `?montana` lists the sources. The 14 photos are from Wikimedia Commons, most of them taken in Montana by Matt Lavin; their authors and licenses are in the package's `COPYRIGHTS` file. ## A diagram of the key `keyDiagram()` draws any key top-down: each question in a blue box, its leads below it, and each species in a green box with its photo. ```{r, eval = FALSE} keyDiagram(k, "montana-key.svg") ``` ```{r, echo = FALSE} knitr::asis_output(paste0("