Error(s) in re-building vignettes:
  ...
--- re-building ‘ipdw2.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.
Loading required package: gdistance
Loading required package: raster
Loading required package: sp
Loading required package: igraph

Attaching package: 'igraph'

The following object is masked from 'package:raster':

    union

The following objects are masked from 'package:stats':

    decompose, spectrum

The following object is masked from 'package:base':

    union

Loading required package: Matrix

Attaching package: 'gdistance'

The following object is masked from 'package:igraph':

    normalize

rgdal: version: 1.5-12, (SVN revision 1018)
Geospatial Data Abstraction Library extensions to R successfully loaded
Loaded GDAL runtime: GDAL 2.2.4, released 2018/03/19
Path to GDAL shared files: /usr/local/share/gdal
GDAL binary built with GEOS: TRUE 
Loaded PROJ runtime: Rel. 5.2.0, September 15th, 2018, [PJ_VERSION: 520]
Path to PROJ shared files: (autodetected)
Linking to sp version:1.4-2
Loading required package: spatstat.data
Loading required package: nlme

Attaching package: 'nlme'

The following object is masked from 'package:raster':

    getData

Loading required package: rpart

spatstat 1.64-1       (nickname: 'Help you I can, yes!') 
For an introduction to spatstat, type 'beginner' 


Attaching package: 'spatstat'

The following objects are masked from 'package:igraph':

    diameter, edges, is.connected, vertices

The following objects are masked from 'package:raster':

    area, rotate, shift

Quitting from lines 128-133 (ipdw2.Rmd) 
Error: processing vignette 'ipdw2.Rmd' failed with diagnostics:
var1 : data item in gstat object and newdata have different coordinate reference systems
--- failed re-building ‘ipdw2.Rmd’

SUMMARY: processing the following file failed:
  ‘ipdw2.Rmd’

Error: Vignette re-building failed.
Execution halted