Determine whether a string contains an Integer or a Float in Ruby -

let's input string, , know whether contains integer or float.

for example:

input_1 = "100" input_2 = "100.0123" 

now, let's take account following:

input_1.respond_to?(:to_f) # => true  input_1.is_a?(float)       # => false input_1.is_a?(fixnum)      # => false input_1.to_f?              # => 100.0  input_2.respond_to?(:to_i) # => true input_2.is_a?(integer)     # => false input_2.is_a?(fixnum)      # => false input_2.to_i               # => 100 

in cases above, can't determine whether string contains integer or float. there way in ruby determine whether string contains fixnum or float?

you use regular expressions:

n = '100.0'  if n =~ /\a\d+\z/   puts 'integer' elsif n =~ /\a\d+\.\d+\z/   puts 'float' else   puts 'not integer or float' end 

edit regular expressions taste.