Re: Simple String question

*To*: mathgroup at smc.vnet.net*Subject*: [mg110723] Re: Simple String question*From*: David Bailey <dave at removedbailey.co.uk>*Date*: Sat, 3 Jul 2010 08:19:01 -0400 (EDT)*References*: <i0k2ft$jra$1@smc.vnet.net>

On 02/07/10 07:54, S. B. Gray wrote: > I have strings like foo="623 715". foo will always be 3 digits, space, 3 > digits. I need to put each set of digits in numerical order and then put > the two triples in order. This would give 157 236. There must be a > simple way to do this, but I see nothing under string sorting. > This splits out the two 3-digit codes, splits these into individual characters using Characters[], and sorts the result before reassembling each string. Then I compare the numerical value of the two expressions, and return the appropriate ordering: In[3]:= foo = "623 715" Out[3]= "623 715" In[4]:= str1 = StringTake[foo, 3]; In[5]:= str2 = StringDrop[foo, 4]; In[9]:= str1 = StringJoin @@ Sort@Characters[str1] Out[9]= "236" In[10]:= str2 = StringJoin @@ Sort@Characters[str2] Out[10]= "157" In[11]:= If[ToExpression[str1] < ToExpression[str2], str1 <> " " <> str2, str2 <> " " <> str1] Out[11]= "157 236" Of course, you may want to join this code together into a single function, but it is nice to see the separate steps before creating a black box! David Bailey http://www.dbaileyconsultancy.co.uk