Q:

I have a dataframe of words and I would like to filter out rows that have numbers in word column in R

So I have a df with a list of words and their frequencies. I would like to filter out rows with numbers; since it's mostly characters however R is recognizing every entry as a character. 
I attempted:
test <- test %>%
filter(word == as.character(word)

But this did not work.
test <- structure(list(word = c("data", "summit", "research", "program", 
"analysis", "study", "evaluation", "minority", "experience", "department", 
"statistical", "Experience", "business", "design", "education", 
"response", "7", "sampling", "learning", "5"), n = c(213L, 
131L, 101L, 98L, 90L, 84L, 82L, 82L, 76L, 72L, 65L, 63L, 60L, 
58L, 58L, 58L, 56L, 55L, 50L, 50L)), row.names = c(NA, -20L), class = c("tbl_df", 
"tbl", "data.frame"))

Additionally, is there a way to make all entries lower case?
I would like to see a df with no rows that have a number for row as well as all lower case entries (which would later be grouped).

A:

You can do:
test %>%
 mutate(word = tolower(word)) %>%
 filter(!grepl("[^A-Za-z]", word))

   word            n
   <chr>       <int>
 1 data          213
 2 summit        131
 3 research      101
 4 program        98
 5 analysis       90
 6 study          84
 7 evaluation     82
 8 minority       82
 9 experience     76
10 department     72
11 statistical    65
12 experience     63
13 business       60
14 design         58
15 education      58
16 response       58
17 sampling       55
18 learning       50

