Importing numerical data from RTF file

Question

This might be a very simple question but I have been struggling with it for a couple of hours, so thought maybe someone here can show me a quick way of solving it.

I have a file in rtf format (Triangles.rtf) https://drive.google.com/file/d/0B_DoKsn6afPMRTNHUW93NEEwc1U/edit?usp=sharing

Now I am trying to load the file by typing a = Import["PATH_TO_FILE/Triangles.rtf","Table"] which seems to return a list of lists. So far it seems fine, for example a[[1]] returns {3 0 2 1}. Head[a[[1]]] returns list and Head[a[[1,1]]] returns String. Then I try to convert string into number by ToExpression[a] but here we get a list of Null!

can anyone please tell me how to convert my imported data into a 2d array (list of list that is) so that I can use the numerics?

Answer 1

While I completely agree with Szabolcs on this. I also enjoy playing with file formats being a theoretical chemist. So here is how you would read this specific file:

  readYourFile[file_String] := Module[{str = OpenRead[file], data},
  ReadList[str, String, 5];
  data = ToExpression @ ReadList[str, Table[Record, {4}], 
     RecordSeparators -> {"\\", " ", "\n", "f0", "fs24", "cf0", "}"}];
  Close[str]; data]

Usage:

 data = readYourFile["Triangles.rtf"]

Now you have your numerical data.

{{3, 0, 2, 1}, {3, 3, 5, 4}, {3, 6, 8, 7}, {3, 9, 11, 10}, {3, 12, 14,
   13}, {3, 15, 17, 16}, {3, 18, 20, 19}, {3, 21, 23, 
  22}, <<265434>>, {3, 796326, 796328, 796327}, {3, 796329, 796331, 
  796330}, {3, 796332, 796334, 796333}, {3, 796335, 796337, 
  796336}, {3, 796338, 796340, 796339}, {3, 796341, 796343, 
  796342}, {3, 796344, 796346, 796345}, {3, 796347, 796349, 796348}}

Let's Check:

MatrixQ[data, NumberQ]

True

Answer 2

I am not saying that it is not possible to load data formatted like this from an RTF file using Mathematica, but the proper answer here is really: do not use RTF (Rich Text Format) files to store such data! Just convert the file to a plain text file (txt) using your favourite word processor (WordPad on Windows, TextEdit on Mac) and load the plain text file as a Table. It'll work fine.

RTF files are designed for storing text, including formatting, and are simply not suitable for storing numerical data.