Conditional Import

*To*: mathgroup at smc.vnet.net*Subject*: [mg122359] Conditional Import*From*: sebastian.mansfeld at googlemail.com*Date*: Wed, 26 Oct 2011 17:39:42 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Reply-to*: comp.soft-sys.math.mathematica at googlegroups.com

Hi! I would like to import data from a very large text file. If I import all the data, Mathematica takes around 9 h to complete. Therefore I would like to import conditionally, that is for example only every 5th element. It would probably be best to do this using low level function. I have found a help topic on this (developing an import converter), however I can not get it to work. Specifically, I do not understand how to implement my own import converter, and how I can then use this to only import every 5th element of a file. Thank you!

**Follow-Ups**:**Re: Conditional Import***From:*Leonid Shifrin <lshifr@gmail.com>