Re: String patterns
- To: mathgroup@smc.vnet.net
- Subject: [mg10930] Re: String patterns
- From: Paul Abbott <paul@physics.uwa.edu.au>
- Date: Thu, 12 Feb 1998 20:16:13 -0500
- Organization: University of Western Australia
- References: <6brf6t$e78@smc.vnet.net>
MJE wrote:
> How good is Mathematica at this kind of string manipultion and
> searching?
Here is a basic implementation:
In[1]:= string="I love Mathematica"; In[2]:= chars=Characters[string]
In[3]:= ToUpperCase[chars]
Select all upper case letters (and " ",".","-",":"):
In[4]:= Select[%,UpperCaseQ[#]||
MemberQ[ToCharacterCode/@{" ",".","-",":"},ToCharacterCode[#]]&]
Form the trigraphs explicitly
In[5]:= trigraphs=Apply[StringJoin,Partition[%,3,1],{1}]
and compute the frequencies:
In[6]:=<<Statistics`DataManipulation` In[6]:=
Reverse/@(Frequencies[trigraphs]//Sort//Reverse)//TableForm
Out[6]//TableForm=
MAT 2
VE 1
TIC 1
THE 1
OVE 1
MA 1
...
There is probably a neat pattern-matching way of computing the
frequencies without constructing the trigraphs explicitly.
Cheers,
Paul
____________________________________________________________________
Paul Abbott Phone: +61-8-9380-2734
Department of Physics Fax: +61-8-9380-1014
The University of Western Australia Nedlands WA 6907
mailto:paul@physics.uwa.edu.au AUSTRALIA
http://www.pd.uwa.edu.au/~paul
God IS a weakly left-handed dice player
____________________________________________________________________