> library(RSentiment)
> calculate_sentiment("This a good book")
[1] "Processing sentence: this a good book"
              text sentiment
1 This a good book  Positive
> calculate_sentiment("This a very good book")
[1] "Processing sentence: this a very good book"
                   text     sentiment
1 This a very good book Very Positive
> calculate_sentiment(c("This a very good book", "This is a very bad newspaper"))
[1] "Processing sentence: this a very good book"
[1] "Processing sentence: this is a very bad newspaper"
                          text     sentiment
1        This a very good book Very Positive
2 This is a very bad newspaper Very Negative
> calculate_score("This a good book")
[1] "Processing sentence: this a good book"
1 
1 
> calculate_score("This a bad book")
[1] "Processing sentence: this a bad book"
 1 
-1 
> calculate_score("This a book")
[1] "Processing sentence: this a book"
1 
0 
> calculate_custom_score("This a book", c("book"), c("newspaper"))
[1] "Processing sentence: this a book"
1 
1 
> calculate_custom_score("This a newspaper", c("book"), c("newspaper"))
[1] "Processing sentence: this a newspaper"
 1 
-1 
> calculate_custom_sentiment("This a newspaper", c("book"), c("newspaper"))
[1] "Processing sentence: this a newspaper"
              text sentiment
1 This a newspaper  Negative
> calculate_custom_sentiment("This a book", c("book"), c("newspaper"))
[1] "Processing sentence: this a book"
         text sentiment
1 This a book  Positive
> calculate_custom_sentiment("This is a good movie", c("book"), c("newspaper"))
[1] "Processing sentence: this is a good movie"
                  text sentiment
1 This is a good movie   Neutral
> 
