Re: How to read a data file in text format?_from a new learner

*To*: mathgroup at smc.vnet.net*Subject*: [mg62414] Re: How to read a data file in text format?_from a new learner*From*: Bill Rowe <readnewsciv at earthlink.net>*Date*: Wed, 23 Nov 2005 01:13:19 -0500 (EST)*Sender*: owner-wri-mathgroup at wolfram.com

On 11/22/05 at 4:42 AM, readnewsciv at earthlink.net (Bill Rowe) wrote: >On 11/21/05 at 3:54 AM, yanshanguke at 163.com (deepthinker) wrote: >>I want to import a data file that produced by spectrometer into >>mathemathica and fit the data. The file is in text format >>("data.txt"). The data in the file is characters: first line:some >>descriptions. second line: 200, 45.5. third line: 201,44.3. and so >>on. If you open the file "data.txt", you will see: >>transmission ratio by UV-3150 >>200, 45.5 >>201,44.3 >>202,44.6 >>203,46.7 >>.... >>1,000,75.5 >>1,000,76.3 >>How to import these data in to mathematica 5.0 and plot the figure? >Probably the simplest way to deal with this file would be to use >Import. That is: >data=Cases[Import["data.txt", "CSV"], {_?NumberQ,_?NumberQ}]; >ListPlot[data]; >Should do what you want. In looking over my comments above, I realized I made an assumption that may not be valid. In possing the problem a comma character appears to be used in two distinct ways, as a field separator and as a separator within a number to improve readability. If the file literally has this format, there will be no simple/easy way to read the data into Mathematica or any other program for that matter. The point is if a comma is interpreted as a field separator, then the line 1,000,75.3 will be seen as three numbers 1, 0, and 75.3. But if the comma is interpreted as part of a number this line is likely to be interpreted as 100075.3, a single number. When I suggested using Import I assumed this line would actually appear in the file as 1000,75.5 That is the comma will always be a field separator which is how it would be treated by Import. -- To reply via email subtract one hundred and four