How to suppress warnings globally

[ducati]

I've tried:

{r box_df, echo = FALSE, message = FALSE, class.warning = NULL}

and

options(warn = -1)

I believe either statement should stop warnings from appearing in the knit file, but they don't. class.warning = FALSE doesn't, either. What's the correct way to suppress warning messages for an entire .Rmd file?

[ducati]

It seems both statements must be included. Either one alone does nothing , but using both does suppress warnings. No idea why -- I'd think one should be enough.

[FJCC]

I think you can suppress them in an option chunk placed just after the yaml header
```{r setup, include=FALSE}
knitr::opts_chunk$set(warning = FALSE)
```

[ducati]

@FJCC

knitr::opts_chunk$set(warning = FALSE)

You're right, and it's global. Thanks!