--- re-building ‘nloptr.Rmd’ using rmarkdown

processing vignette 'nloptr.Rmd' failed with diagnostics:

Vignette re-building failed.

Build process failed

Process completed with exit code 1.

The vignette title specified in \VignetteIndexEntry{} is different from the title in the YAML metadata. The former is "nloptr", and the latter is "Introduction to `nloptr`: an R interface to NLopt^[This package should be considered in beta and comments about any aspect of the package are welcome. This document is an R vignette prepared with the aid of `knitr` [@xie:2014; @xie:2015; @xie:2016]. Financial support of the UK Economic and Social Research Council through a grant (RES-589-28-0001) to the ESRC Centre for Microdata Methods and Practice (CeMMAP) is gratefully acknowledged.]". If that is intentional, you may set options(rmarkdown.html_vignette.check_title = FALSE) to suppress this check.