I need to import measured readings stored in a .txt file using arduino 0023.
Plz help as soon as possible.
Be more specific on what you are trying to do here. I might be able to help you because it is similar to something I am working on.
Provide a sample data file. Post it here, with explanation. How much data do you have, in KB?
hi 
actually the size of the file is around 700kb which is a .txt file.
the file composes of many columns of different data.
the data has to be searched and the required column of data needs to be processed using the kit.
Where is the file stored? Is it on an SD card attached to the Arduino?
hi friends,
The .txt file is stored in my hard disc,it contains columns of lat,lon ,alt for certain flight path.I doing kalman filter programming in arduino,so i have to read that data in arduino and to store in array
Arduino has very limited storage space. Without an SD card, it is unable to store that much data, 32KB to be the max amount for UNO and 256KB to be the max amount for MEGA 2560.
How large is your array going to be? Number of elements and what data type?
hi friends,
My text file contains three column with 2048 rows ,it is a float data type.how can i read if that file in SD card?
Thanks for all for kind reply
Go to arduino playground and download an sd card library.
When doing the processing, do you need to process all that data together? You are not answering this question. Arduino only has 2KB RAM to store an array so do some math.
As you clearly observe, that data's not fitting in an Uno any time soon. However, perhaps it doesn't matter - from the wikipedia entry:
Because of the algorithm's recursive nature, it can run in real time using only the present input measurements and the previously calculated state; no additional past information is required