R Grep: Is There an and Operator

R grep: is there an AND operator?

Thanks to this answer, this regex seems to work. You want to use grepl() which returns a logical to index into your data object. I won't claim to fully understand the inner workings of the regex, but regardless:

x <- c("imageUploaded,people.jpg,more,comma,separated,stuff", "imageUploaded", "people.jpg")

grepl("(?=.*imageUploaded)(?=.*people\\.jpg)", x, perl = TRUE)
#-----
[1]  TRUE FALSE FALSE

R grep with 'AND' logic

You could try

grep('hive-jdbc.*standalone', jars) # 'hive-jdbc' followed by 'standalone' 

or

grepl('hive-jdbc', jars) & grepl('standalone', jars) # 'hive-jdbc' AND 'standalone'

Grep in R using AND

Lookahead is not needed to do this, you can use the alternation operator in context.

grep('five.*six|six.*five', object)

If you know that "five" will precede "six" on the line, you don't even need the alternatives:

grep('five.*six', object)

Is it possible to use an AND operator in grepl()?

To search for a string having both "a" and "b"

grepl("a", x) & grepl("b", x)

or

grepl("a.*b|b.*a", x)

If we know the order of the two parts then we can omit one of the two halves of the last grepl. For example, in the case of the query in the question this would be sufficient to find a string that starts with 55 and contains Roof

grepl("^55.*Roof", x)

Another possibility is

grep("a.*b", paste(x, x))

If the terms searched for have space then use a different sep= in paste.

Boolean operators on grep in a dataframe

Just use the or in your regular expression.

people[!grepl("Yamazaki|Xavier", people$Name), ]

            Name PhoneX
5 Edward Zachary   7573
6  Fiona Zachary   9457

OR / AND operator in grepl o str_detect

We may use ^(?!.*Wag).*RX4 for that, where (?!.*Wag) is a negative lookahead throughout all the string. For instance,

grep('^(?!.*Wag).*RX4', c("Wag RX4 bag", "bag RX4 Wag", "bag RX4 bag"), perl = TRUE)
# [1] 3

So, in your case that would be

dplyr::filter(mtcars, grepl('^(?!.*Wag).*RX4', type, perl = TRUE))
#   mpg cyl disp  hp drat   wt  qsec vs am gear carb      type
# 1  21   6  160 110  3.9 2.62 16.46  0  1    4    4 Mazda RX4

I'd agree that this pattern isn't really obvious, so you may want to do it in two steps, allowing to use usual AND and NOT:

dplyr::filter(mtcars, grepl('RX4', type) & !grepl('Wag', type))
#   mpg cyl disp  hp drat   wt  qsec vs am gear carb      type
# 1  21   6  160 110  3.9 2.62 16.46  0  1    4    4 Mazda RX4

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