ASCII Character Jumble

Question

Write a program that takes as its input a string consisting of printable characters (ASCII 20-7E) and an integer n in [2,16] and performs the following modification to the string.

• Each character in the string is converted to its ASCII code (the examples given are in hexadecimal, though base 10 is also acceptable).
• The ASCII codes are converted to base n and are concatenated together.
• The new string is split every other character. If there are an odd number of characters, then the last character is removed entirely.
• Printing ASCII codes (in base 16) are converted back into their characters, whereas non-printing ASCII codes are removed.
• The resulting string is printed.

Test case

Input

Hello, World!
6

Steps

Hello, World!
48 65 6C 6C 6F 2C 20 57 6F 72 6C 64 21
2002453003003031125222330331030024453
20 02 45 30 03 00 30 31 12 52 22 33 03 31 03 00 24 45

The output of this program is E001R"31$E.

---

This is code golf, so standard rules apply. Shortest code in bytes wins.

Answer 1

Pyth - 22 bytes

Hope to golf a lot more, pretty straightforward.

sfq3l`TmCid16csjRQCMz2

Try it online here.

Answer 2

CJam, 33 bytes

q~:i\fb:~0+2/W<Gfb:c' ,-'ÿ),127>-

Takes input in the form 6 "Hello, World!". Test it here.

See Dennis's answer for a similar but better solution with a nice explanation.

Answer 3

Bash + common linux utils, 118

printf %s "$1"|xxd -p|sed -r "s/../\U& /g;y/ /n/;s/^/dc -e$2o16i/e;s/../& /g;s/ .$//;"|xxd -rp|sed 's/[^[:print:]]//g'

Answer 4

JavaScript (ES6), 137 147

Using the most verbose functions available in JavaScript

f=(s,b)=>alert(s.replace(/./g,x=>x.charCodeAt().toString(b)).match(/../g).map(x=>(x=String.fromCharCode('0x'+x))<='~'&x>' '?x:'').join``)

// Just for test purpose, redefine alert()
alert=x=>document.write('<pre>'+x+'</pre>')

f('Hello, World!',6)
f('PORK',3)

Answer 5

CJam, 24 bytes

l:irifbe_2/{Gbc',32>&}/

Note that there is a DEL character (0x7F) between ' and ,. Try it online in the CJam interpreter.

How it works

l:i                     Read a line from STDIN and cast each char to integer. 
   ri                   Read another integer (base) from STDIN.
     fb                 Convert each integer from line 1 to that base.
       e_2/             Flatten and split into chunks of length 2.
                        If the last chunk has only one element, it will get
                        converted into a control character, which will be
                        removed later.
          {         }/  For each digit pair:
           Gb             Convert the pair from base 16 to integer.
             c            Cast to character.
              ',          Push the string of ASCII characters up to '~'.
                32>       Remove the first 32 (control characters).
                   &      Intersect.

Answer 6

Julia, 118 bytes

f(s,n)=join(map(i->(c=string(Char(parse(Int,i,16))))^isprint(c),matchall(r"..",join(map(i->base(n,Int(i)),[s...])))))

Ungolfed:

function f(s::AbstractString, n::Integer)
    # Construct an array of ASCII codes in base n
    v = map(i -> base(n, Int(i)), [s...])

    # Join into a string and get all pairs, truncating
    # to an even length
    m = matchall(r"..", join(v))

    # Parse each pair as an integer in base 16, get the
    # character associated with that code point, convert
    # to a string, and include if it's printable
    x = map(i -> (c = string(Char(parse(Int, i, 16)))^isprint(c), m)

    # Join as a string and return
    return join(x)
end

Answer 7

TeaScript, 23 bytes

TeaScript is JavaScript for golfing

£lc¡T(y©K(2)ßC(P(l,16±µ

Relatively straight-forward but delightfully short. I can probably golf down a few more characters with some more operators. A few other new features might also be able to be used to cut down some bytes.

Ungolfed && Explanation

x.l(#
    l.c().T(y)
).K(2)
.m(#
    C(
      P(l,16)
    )
).j``

Answer 8

Mathematica, 134 bytes

Print@FromCharacterCode@Select[#~FromDigits~16&/@StringPartition[""<>ToCharacterCode@InputString[]~IntegerString~Input[],2],31<#<127&]

If a function is allowed:

Mathematica, 112 bytes

FromCharacterCode@Select[#~FromDigits~16&/@StringPartition[""<>ToCharacterCode@#~IntegerString~#2,2],31<#<127&]&

Answer 9

Ruby 92

->s,n{o=''
s.chars.map{|x|x.ord.to_s n}.join.scan(/../).map{|x|x>?2&&x<?8&&o<<x.to_i(16)}
o}

Online test here.

Answer 10

Python 2, 174 bytes

def J(a,b,i=0):
 h=r=''
 B=lambda n,b:n*'x'and B(n/b,b)+chr(48+n%b+7*(n%b>9))
 for c in a:h+=B(ord(c),b)
 while i<len(h):v=int(h[i:i+2],16);r+=chr(v)*(31<v<127);i+=2
 print r

Try it here

Not really the best tool for the job. Since Python has no convert-to-arbitrary-base function, I had to implement my own. That was fun, at least--particularly finding a [marginally] shorter expression for the digits than "0123456789ABCDEF"[n%b]. For iterating over two characters at a time, I found a while loop was slightly shorter than a functional approach.

181 bytes as a full program:

B=lambda n,b:n*'x'and B(n/b,b)+chr(48+n%b+7*(n%b>9))
a=raw_input()
b=input()
h=r=''
for c in a:h+=B(ord(c),b)
i=0
while i<len(h):v=int(h[i:i+2],16);r+=chr(v)*(31<v<127);i+=2
print r

Answer 11

MATLAB, 103 bytes

function k(s,n),b=dec2base(s,n)';b(~cumsum(b-'0',1))='';c=base2dec(textscan(b,'%2c'),16)';char(c(c>31))

I've written a function k that takes a string s and an integer n as input. e.g.:

k('Hello, World!',6)

gives

 E001R"31$E

Most annoying thing I had to work around is leading zeros showing up when converting to base n. Getting these out of the array that was to be split after every 2nd character cost quite a lot of bytes. Not sure if it is possible to save any more bytes using this approach.

Answer 12

PHP - 286 bytes

Put the string in $s and the integer in $b.

<?php $s=$_GET["s"];$b;$m="array_map";echo implode($m(function($v){return ctype_print($v)?$v:"";},$m("chr",$m("hexdec",str_split(strlen(implode($a=$m(function($v){global$b;return base_convert($v,16,$b);},$m("dechex",$m("ord",str_split($s))))))%2==1?substr(implode($a),0,-1):$a,2)))));?>

Pass the value to GET["s"].