add link to spatstat.explore [no chk]

Author: ctoney

README.Rmd

@@ -49,7 +49,9 @@ pak::pak("firelab/FIAstemmap")
 
 ### Predict tree crown width
 
-The data frame `cw_coef` contains a curated set of linear regression coefficients for predicting crown width from stem diameter of tree species in the conterminous US (see `?cw_coef`). The method for crown width prediction attempts to avoid extrapolation beyond the range of the model fitting data by providing reasonable fall backs for the obvious cases. Details are given in the documentation for `calc_crwidth()`. The input is a data frame of tree records which must have columns `SPCD` (FIA species code), `STATUSCD` (FIA tree status code, `1` = live) and `DIA` (FIA tree diameter). FIA distribute data in [United States customary units](https://en.wikipedia.org/wiki/United_States_customary_units) with tree diameter given in inches, height in feet, and area in acres. Convenience functions are provided for converting to and from SI units[^1^](#footnotes) (`in_to_cm()`, `cm_to_in()`, `ft_to_m()`, `m_to_ft()`, `ac_to_ha()`, `ha_to_ac()`).
+The data frame `cw_coef` contains a curated set of linear regression coefficients for predicting crown width from stem diameter of tree species in the conterminous US (see `?cw_coef`). The method for crown width prediction attempts to avoid extrapolation beyond the range of the model fitting data by providing reasonable fall backs for the obvious cases. Details are given in the documentation for `calc_crwidth()`.
+
+The input is a data frame of tree records which must have columns `SPCD` (FIA species code), `STATUSCD` (FIA tree status code, `1` = live) and `DIA` (FIA tree diameter). FIA distribute data in [United States customary units](https://en.wikipedia.org/wiki/United_States_customary_units) with tree diameter given in inches, height in feet, and area in acres. Convenience functions are provided for converting to and from SI units[^1^](#footnotes) (`in_to_cm()`, `cm_to_in()`, `ft_to_m()`, `m_to_ft()`, `ac_to_ha()`, `ha_to_ac()`).
 
 The `plantation` dataset used here is an example tree list included in the package.
 
@@ -83,7 +85,7 @@ plot_crowns(tree_list, subplot = 4, microplot = TRUE,
             main = "Loblolly pine plantation microplot 4")
 ```
 
-Helper functions facilitate the analysis of FIA tree lists as spatial point patterns using the **spatstat** library. `create_fia_ppp()` returns an object of class `"ppp"` representing the point pattern of an FIA tree list in the 2-D plane. This object can be used with functions of **spatstat.explore** which provide additional plotting capabilities, descriptive spatial statistics, and other exploratory data analysis.
+Helper functions facilitate the analysis of FIA tree lists as spatial point patterns using the **spatstat** library. `create_fia_ppp()` returns an object of class `"ppp"` representing the point pattern of an FIA tree list in the 2-D plane. This object can be used with functions of [**spatstat.explore**](https://cran.r-project.org/package=spatstat.explore) which provide additional plotting capabilities, descriptive spatial statistics, and other exploratory data analysis.
 
 ```{r spatstat-explore}
 ## Create a spatstat point pattern object for the pine plantation tree list.

README.md

@@ -68,8 +68,9 @@ coefficients for predicting crown width from stem diameter of tree
 species in the conterminous US (see `?cw_coef`). The method for crown
 width prediction attempts to avoid extrapolation beyond the range of the
 model fitting data by providing reasonable fall backs for the obvious
-cases. Details are given in the documentation for `calc_crwidth()`. The
-input is a data frame of tree records which must have columns `SPCD`
+cases. Details are given in the documentation for `calc_crwidth()`.
+
+The input is a data frame of tree records which must have columns `SPCD`
 (FIA species code), `STATUSCD` (FIA tree status code, `1` = live) and
 `DIA` (FIA tree diameter). FIA distribute data in [United States
 customary
@@ -152,8 +153,10 @@ Helper functions facilitate the analysis of FIA tree lists as spatial
 point patterns using the **spatstat** library. `create_fia_ppp()`
 returns an object of class `"ppp"` representing the point pattern of an
 FIA tree list in the 2-D plane. This object can be used with functions
-of **spatstat.explore** which provide additional plotting capabilities,
-descriptive spatial statistics, and other exploratory data analysis.
+of
+[**spatstat.explore**](https://cran.r-project.org/package=spatstat.explore)
+which provide additional plotting capabilities, descriptive spatial
+statistics, and other exploratory data analysis.
 
 ``` r
 ## Create a spatstat point pattern object for the pine plantation tree list.