Error in R Markdown: Data must be a character vector

is a syuzhet function with a signature

get_nrc_sentiment(char_v, cl = NULL, language = "english", lowercase = TRUE)

where char_v is a character vector, e.g.

c("alpha", "beta")

The function is being given as char_v AttdAI,which is the return value of convert.tm.to.character from the textreg package. As noted in it's documentation

sometimes you need to convert your tm object to a string vector for various reasons, the main one being handing it to the C++ method. It is ugly, \dots
It is therefore a possibly better decision to pass a filename to a plain-text file to the textreg call to be loaded by C++ directly. See textreg

which indicates that get_nrc_sentiment may fail, there is an alternative and suggests that it is not worthwhile attempting to find why it might work in the console but not in the rendering.

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