add positive, negative, between

src/faker.cr

@@ -69,4 +69,10 @@ module Faker
       "Hoaydaaa"
     end
   end
+
+  # Generates a random value between the interval
+  def self.rand_in_range(from, to)
+    from, to = to, from if to < from
+    Random.new.rand(from..to)
+  end
 end

src/faker/number.cr

@@ -13,5 +13,35 @@ module Faker
       r_d = number(r_digits)
       "#{l_d}.#{r_d}"
     end
+
+    def self.between(from = 1.00, to = 5000.00)
+      Faker.rand_in_range(from, to)
+    end
+
+    def self.positive(from = 1.00, to = 5000.00)
+      random_number = between(from, to)
+      greater_than_zero(random_number)
+    end
+
+    def self.negative(from = -5000.00, to = -1.00)
+      random_number = between(from, to)
+      less_than_zero(random_number)
+    end
+
+    private def self.greater_than_zero(number)
+      if number > 0
+        number
+      else
+        number * -1
+      end
+    end
+
+    private def self.less_than_zero(number)
+      if number < 0
+        number
+      else
+        number * -1
+      end
+    end
   end
 end