From: Clement Ow [mailto:clement.ow / asia.bnpparibas.com] 
# ex = {}
# ex[0] = [".xls", ".ini", "20080326"]
# ex[1] = ["RVG", ".xls", ".rb"]
# The result i would want:
# str1 = [".xls", ".ini", ".xls", ".rb"]
# str2 = ["20080326", "RVG"]

Hi Clement, there are many ways.
ff is just one way,

ex = {}
#=> {}
ex[0] = [".xls", ".ini", "20080326"]
#=> [".xls", ".ini", "20080326"]
ex[1] = ["RVG", ".xls", ".rb"]
#=> ["RVG", ".xls", ".rb"]

ex.values
#=> [[".xls", ".ini", "20080326"], ["RVG", ".xls", ".rb"]]

so,

str1,str2=ex.values.flatten.partition{|x| x=~/\./}
#=> [[".xls", ".ini", ".xls", ".rb"], ["20080326", "RVG"]]

str1
#=> [".xls", ".ini", ".xls", ".rb"]
str2
#=> ["20080326", "RVG"]

kind regards -botp