What is the efficient and straightforward code for finding array elements in a string. For example:
a = Array['aaa', 'bbb', 'ccc', 'ddd', 'eee']
b = "This is the sample string with aaa , blah blah"
c = someFunction(b, a)
puts c
=> ['aaa']
Suppose a array have 100 elements, I want to know which of array element is found in the string. I should match exacct word. So xbbb, bbaa, ... not matched.
I think this is one of the possible solutions:
def some_method(string, array)
string.split & array
end
a = Array['aaa', 'bbb', 'ccc', 'ddd', 'eee']
b = "This is the sample string with aaa , blah blah"
> some_method(b, a)
=> ['aaa']
a = Array['aaa', 'bbb', 'ccc', 'ddd', 'eee']
b = "This is the sample string with xaaa , blah blah"
> some_method(b, a)
=> []
Set. Sets have a faster lookup time, and therefore should in theory have a faster intersection result.def find_elements(my_string, my_array)
my_string.split & my_array
end
You can split the string into an array and then find the intersection of both arrays using & or even intersection if you are on ruby 2.7. This will return an array containing all of the unique matching elements.
One way I found is like below -
array = Array['aaa', 'bbb', 'ccc', 'ddd', 'eee']
string = "This is the sample string with aaa , blah blah"
found = []
array.each { |a| found << a if string.include? a }
puts found
=> ["aaa"]
EDIT
After knowing another use case where it is needed exact match and as include? matches 'aaa' even if it is in 'xxaaa', one possible solution is using Set Intersection with Arrays in Ruby -
def some_methodd(array, string)
string.split & array
end
Then it will return the exact match.
=> ["aaa"]
"aaa" should not be matched if the string ended "...string with xaaa , blah blah".
include? has this edge case. I am grateful to you.You can also use #select with a regular expression to determine which array elements are in the string.
def check_string(ary, str)
ary.select do |e|
str =~ /\b#{e}\b/
end
end
p check_string(%w(aaa bbb ccc), 'Here is a saaample bbb string ccc') # => ['bbb', 'ccc']
This gives you a lot of flexibility as to what matches and what doesn't, since if you want to change that, all you have to do is change the regex. This example assumes that you want whole word matches with words in an array.
'aaa'?ain your stringb. Also, please make clear whether"xbbb", if it were in the string, would be a match.