Replacing whitespace in a list with comma and turning into sublists

Question

I have the following list:

l={"1 atattaggtt tttacctacc caggaaaagc caaccaacct
61 ctctaaacga actttaaaat ctgtgtagct gtcgctcggc
121 gcagtataaa caataataaa"}

which I want to turn into:

{{{1,{"atattaggtt","tttacctacc","caggaaaagc","caaccaacct"}},
    {61,{"ctctaaacga","actttaaaat","ctgtgtagct","gtcgctcggc"}},
    {121,{"gcagtataaa","caataataaa"}}}

I wonder how one does this?

Update: I know that StringReplace[l, WhitespaceCharacter -> ","] gives me:

{"1,atattaggtt,tttacctacc,caggaaaagc,caaccaacct,61,ctctaaacga,\
actttaaaat,ctgtgtagct,gtcgctcggc,121,gcagtataaa,caataataaa"}

Yet I don't know how to sublist this as above.

Answer 1

You may use StringCases with StringExpression.

StringCases[
  n : NumberString ~~ s : (WhitespaceCharacter ~~ LetterCharacter ..) .. :> 
    {FromDigits@n, StringSplit@s}
]@l

{{{1, {"atattaggtt", "tttacctacc", "caggaaaagc", "caaccaacct"}}, 
  {61, {"ctctaaacga", "actttaaaat", "ctgtgtagct", "gtcgctcggc"}}, 
  {121, {"gcagtataaa", "caataataaa"}}}} 

Hope this helps.

Answer 2

{First[#], Rest[#]} & /@ ImportString[#, "Table"] & /@ l

(*    {{{1, {"atattaggtt", "tttacctacc", "caggaaaagc", "caaccaacct"}},
        {61, {"ctctaaacga", "actttaaaat", "ctgtgtagct", "gtcgctcggc"}},
        {121, {"gcagtataaa", "caataataaa"}}}}                              *)

Answer 3

Another way using regular expressions.

StringSplit[l, RegularExpression["(?=[A-Z]|(?<!\\d)\\d)"]] // 
  Map[StringSplit /* ({First@#, Rest@#} &), #, {-1}] &

Answer 4

StringCases[l,
  RegularExpression["([1-9]+)([a-t\s]+)"]:> {"$1", StringSplit["$2"]}
]

{{{1, {atattaggtt, tttacctacc, caggaaaagc, caaccaacct}}, {61, {ctctaaacga, actttaaaat, ctgtgtagct, gtcgctcggc}}, {121, {gcagtataaa, caataataaa}}}}

Original Answer

StringCases[l,RegularExpression["([1-9]+)([a-z\s]+)"]:> {"$1", "$2"}]
  // MapAt[StringSplit, #, {All,All,2}]&

Answer 5

Map[{FromDigits @ #, {##2}} & @@@ # & @* StringSplit] @ StringSplit[l, "\n"]

{{{1, {"atattaggtt", "tttacctacc", "caggaaaagc", "caaccaacct"}}, 
  {61, {"ctctaaacga", "actttaaaat", "ctgtgtagct", "gtcgctcggc"}},
  {121, {"gcagtataaa", "caataataaa"}}}}

Also

f = Normal[{#, DeleteCases[{##2}, ""]} & @@@ SemanticImportString[#]] &;
f /@ l

{{{1, {"atattaggtt", "tttacctacc", "caggaaaagc", "caaccaacct"}}, 
  {61, {"ctctaaacga", "actttaaaat", "ctgtgtagct", "gtcgctcggc"}}, 
  {121, {"gcagtataaa", "caataataaa"}}}}

and

f2 = {FromDigits @ #, {##2}} & @@@ 
      Split[StringSplit @ #, Not @* StringMatchQ[NumberString] @* First] &;
f2 /@ l

 {{{1, {"atattaggtt", "tttacctacc", "caggaaaagc", "caaccaacct"}},
   {61, {"ctctaaacga", "actttaaaat", "ctgtgtagct", "gtcgctcggc"}},
   {121, {"gcagtataaa", "caataataaa"}}}}

Answer 6

So after playing a bit, I found the solution:

x0 = StringSplit[l, Whitespace] // Flatten // ToExpression;
x1 = Split[x0, ! IntegerQ[#2] &];
x2 = Map[Drop[#, 1] &, x1];
x3 = Table[Map[ToString[#] &, x2[[i]]], {i, Length[x2]}];
x4 = Map[Take[#, 1] &, x1] // Flatten;
final = Transpose[{x4, x3}]

To which I get:

{{1, {"atattaggtt", "tttacctacc", "caggaaaagc", 
   "caaccaacct"}}, {61, {"ctctaaacga", "actttaaaat", "ctgtgtagct", 
   "gtcgctcggc"}}, {121, {"gcagtataaa", "caataataaa"}}}

As desired. Maybe you guys can make this more efficient.