Re: Problems reading text files with embedded delimiters
- To: mathgroup at smc.vnet.net
- Subject: [mg125611] Re: Problems reading text files with embedded delimiters
- From: Rodrigo Murta <murta at rodrigomurta.com>
- Date: Wed, 21 Mar 2012 05:47:55 -0500 (EST)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <jk9bfb$bo1$1@smc.vnet.net>
On Mar 20, 4:26 am, Mark Coleman <markspcole... at gmail.com> wrote: > Hi, > > I'm struggling with importing a large flat file into Mathematica. The file, > which was pulled off one of my company's legacy mainframe systems, > contains about 100 fields and several million rows, including a mix of > dates, reals, and text. The fields are delimited by commas. > > One of the text fields, however, is quite large and contains commas, > line feeds, carriage returns, etc -- lots of characters commonly used > as delimiters. It is also a variable length field. There does not seem > to be anything characters within the field that would allow the > specification of a simple delimiter. I've tried the default Import[] > command as well as various permutations of ReadList[] using Record, > Word, and String specifications. > > I'm wondering if anyone could suggest an approach that would allow me > to read this file. More precisely, is there a way to avoid reading > characters embedded in the large text field that Mathematica thinks are field > delimiters? > > Thanks, > > Mark Hi Mark I didn't completely get your point. What is your delimiter? Your large text is quoted? Can you sendo one example line? Or a toy code? For large text string you could use some low level programming. Maybe this tutorial could help you: http://reference.wolfram.com/mathematica/guide/LowLevelFileOperations.html Go to the stream topic. best regards Murta