[SOLVED] In `dplyr` `filter`， how to parse conditions which are stored in string?

In `dplyr` `filter`， how to parse conditions which are stored in string?

In dplyr filter, how to parse conditions which are stored in string?When there's only one condition, below code can work

library(dplyr)
conditions_string_1 <- "Species=='versicolor'"
iris %>% filter(eval(str2lang(conditions_string_1)))

But when there're two conditions, below code can't work. How to fix it?

conditions_string_2 <- "Species=='versicolor',Sepal.Width>3"
iris %>% filter(eval(str2lang(conditions_string_2)))

Solution

Just gsub the comma to AND (&) or OR (|).

This assumes your column names or conditions don't contain comma.

conditions_string_2 <- "Species=='versicolor',Sepal.Width>3"

iris %>% filter(eval(str2lang(gsub(",", "&", conditions_string_2))))

  Sepal.Length Sepal.Width Petal.Length Petal.Width    Species
1          7.0         3.2          4.7         1.4 versicolor
2          6.4         3.2          4.5         1.5 versicolor
3          6.9         3.1          4.9         1.5 versicolor
4          6.3         3.3          4.7         1.6 versicolor
5          6.7         3.1          4.4         1.4 versicolor
6          5.9         3.2          4.8         1.8 versicolor
7          6.0         3.4          4.5         1.6 versicolor
8          6.7         3.1          4.7         1.5 versicolor