Soundex function

Question

Write the shortest function to generate the American Soundex code for a surname only containing the uppercase letters A-Z. Your function must produce output consistent with all the linked page's examples (given below), although it need not and should not remove prefixes. Hyphens in the output are optional. Have fun!

Note: You may not use the soundex() function included in PHP or equivalents in other programming languages.

The examples:

WASHINGTON W-252
LEE L-000
GUTIERREZ G-362
PFISTER P-236 
JACKSON J-250 
TYMCZAK T-522
VANDEUSEN V-532
ASHCRAFT A-261

Answer 1

Perl, 143 150 characters

sub f{$_="$_[0]000";/./;$t=$&;s/(?<=.)[HW]//g;s/[BFPV]+/1/g;s/[CGJKQSXZ]+/2/g;s/[DT]+/3/g;s/L+/4/g;s/[MN]+/5/g;s/R+/6/g;s/(?<=.)\D//g;/.(...)/;"$t$1"}

This solution contains only regular expressions which are applied one after another. Unfortunately I didn't find a shorter representation with a loop so I hard-coded all the calls into the script.

The same version but a little bit more readable:

sub f{
  $_="$_[0]000";        # take first argument and append "000"
  /./;$t=$&;            # save first char to variable $t
  s/(?<=.)[HW]//g;      # remove and H or W but not the first one
  s/[BFPV]+/1/g;        # replace one or more BFPV by 1
  s/[CGJKQSXZ]+/2/g;    # replace one or more CGJKQSXZ by 2
  s/[DT]+/3/g;          # replace one or more DT by 3
  s/L+/4/g;             # replace one or more L by 4
  s/[MN]+/5/g;          # replace one or more MN by 5
  s/R+/6/g;             # replace one or more R by 6
  s/(?<=.)\D//g;        # remove and non-digit from the result but not the first char
  /.(...)/;"$t$1"       # take $t plus the characters 2 to 4 from result
}

Edit 1: Now the solution is written in form of a function. The previous one was reading/writing from/to STDIN/STDOUT. It cost me seven characters to work around that.

Answer 2

Python, 274 285 241 235 225 200 190 183 179 174 166 161

- Fixed last clause (H or W as consonant separators). Ashcraft now has the right result. - Made the dict smaller - Formating is smaller (doesn't require python 2.6) - Simpler dict search for k - Changed vowel value from '*' to '' and .append to +=[i] - List comprehension FTW - Removed call to upper :D

I Can't golf any further. Actually I did. Now I think I can't golf any further! Did it again...

Using translate table:

def f(n):z=n.translate(65*'_'+'#123#12_#22455#12623#1_2#2'+165*'_').replace('_','');return n[0]+(''.join(('',j)[j>'#']for i,j in zip(z[0]+z,z)if i!=j)+'000')[:3]

Old list comprehension code:

x=dict(zip('CGJKQSXZDTLMNRBFPV','2'*8+'3345561111'))
def f(n):z=[x.get(i,'')for i in n if i not in'HW'];return n[0]+(''.join(j for i,j in zip([x.get(n[0])]+z,z)if i!=j)+'000')[:3]

Old code:

x=dict(zip('CGJKQSXZDTLMNRBFPV','2'*8+'3345561111'))
def f(n):
 e=a=[];k=n[0]in x
 for i in[x.get(i,'')for i in n.upper()if i not in'HW']:
  if i!=a:e+=[i]
  a=i
 return n[0]+(''.join(e)+'000')[k:3+k]

Test:

[f(i) for i in ['WASHINGTON', 'LEE', 'GUTIERREZ', 'PFSTER', 'JACKSON',
                'TYMCZAK', 'VANDEUSEN', 'ASHCRAFT']]

Gives:

['W252', 'L000', 'G362', 'P236', 'J250', 'T522', 'V532', 'A261']

As expected.

Answer 3

eTeX, 377.

\let\E\expandafter
\def\x#1;#2#3{\def\s##1#2{##1\s#3}\edef\t{\s#1\iffalse#2\fi}\E\x\t;}
\def\a[#1#2]{\if{{\fi\uppercase{\x#1,#2};B1F1P1V1C2G2J2K2Q2S2X2Z2D3T3L4M5N5R6A7E7I7O7U7
    H{}W{}Y{}{11}1{22}2{33}3{44}4{55}5{66}6{{}\toks0\bgroup}!}\E\$\t0000!#1}}
\def\$#1,#2{\if#1#2\relax\E\%\else\E\%\E#2\fi}
\def\%{\catcode`79 \scantokens\bgroup\^}
\def\^#1#2#3#4!#5{\message{#5#1#2#3}\end}
\E\a

Run as etex filename.tex [Ashcraft].

Answer 4

J - 99

{.,([:-.&' '@":3{.!.0[:(#~1,}.~:}:)^:#,@(;:@]>:@I.@:(e.&>"0 _~)[#~e.))&'BFPV CGJKQSXZ DT L MN R'@}.

Testing:

  sndx=: {.,([:-.&' '@":3{.!.0[:(#~1,}.~:}:)^:#,@(;:@]>:@I.@:(e.&>"0 _~)[#~e.))&'BFPV CGJKQSXZ DT L MN R'@}.
  test=: ;: 'JACKSON PFISTER TYMCZAK GUTIERREZ ASHCRAFT ASHCROFT VANDEUSEN ROBERT RUPERT RUBIN WASHINGTON LEE'
  (,. sndx&.>) test


+-------+-------+-------+---------+--------+--------+---------+------+------+-----+----------+----+
|JACKSON|PFISTER|TYMCZAK|GUTIERREZ|ASHCRAFT|ASHCROFT|VANDEUSEN|ROBERT|RUPERT|RUBIN|WASHINGTON|LEE |
+-------+-------+-------+---------+--------+--------+---------+------+------+-----+----------+----+
|J250   |P123   |T520   |G362     |A261    |A261    |V532     |R163  |R163  |R150 |W252      |L000|
+-------+-------+-------+---------+--------+--------+---------+------+------+-----+----------+----+

Answer 5

Perl, 110

sub f{$_="$_[0]000";/./;$t=$&;s/(?<=.)[HW]//g;y/A-Z/:123:12_:22455:12623:1_2:2/s;s/(?<=.)\D//g;/.(...)/;$t.$1}

I'm using Howard's solution with my translate table (y/A-Z/table/s instead of every s/[ABC]+/N/g)

Answer 6

PowerShell, 150 161

First try and I'm sure there can be golfed quite a bit more.

filter s{$s=-join$_[1..9]
1..6+'$1','',$_[0]|%{$s=$s-replace('2[bfpv]2[cgjkqsxz]2[dt]2l2[mn]2r2(.)\1+2\D|^.2^'-split2)[++$a],$_}
-join"${s}000"[0..3]}

Works correctly with the test cases from both the linked page and the Wikipedia article:

Jackson, Pfister, Tymczak, Gutierrez, Ashcraft, Ashcroft, VanDeusen, Robert, Rupert, Rubin, Washington, Lee