| Re: read_ascii for many rows / possible to create automatic names for variables [message #57314 is a reply to message #57153] |
Wed, 05 December 2007 09:47   |
britta.mey
Messages: 14
Registered: August 2007
|
Junior Member |
|
|
On Dec 5, 6:15 pm, David Fanning <n...@dfanning.com> wrote:
> Britta writes:
>> Thank you, the file is on its way.
>
> Ah, well, ain't that interesting!
>
> The problem here is that while *most* of your columns
> are separated by blank characters, two of your columns
> are separated by tabs. What this basically means is that
> you should find a gun and shoot the person who created
> this data file. :-)
>
> What is happening is that I used a blank character as
> the separator for calculating the number of columns in
> the file, and because of the two tabs, I come up two
> columns short in the calculation. I calculate 1030 and
> there are really 1032. Thus, my columns are totally
> messed up, and I never read all the data in the file.
>
> So, since these data files are probably identical from one
> run to the next, you could probably just use the number 1032
> for the number of columns and the code would work perfectly.
>
> The other alternative (besides shooting the programmer,
> I mean) is to use a regular expression as the column
> separator in StrSplit. As you are a beginner, and as this
> is something even I don't understand, we will leave it
> to our betters to fill us in on how THIS can be done. :-)
>
> My best guess is that it is something like this:
>
> parts = StrSplit(line, '[ ' + String(9B) + ']+', /REGEX, /EXTRACT)
> cols = N_Elements(parts)
>
> Hope that helps. I haven't see *this* problem before. :-)
>
> Cheers,
>
> David
>
> P.S. It looks to me like I got that expression right from the
> quick test I just ran.
> --
> David Fanning, Ph.D.
> Fanning Software Consulting, Inc.
> Coyote's Guide to IDL Programming:http://www.dfanning.com/
> Sepore ma de ni thui. ("Perhaps thou speakest truth.")
Great, thank's a lot. This works. Could you please short explain what
you have done? Or please tell me, if this is correct, what I
understood...
parts = StrSplit(line, '[ ' + String(9B) + ']+', /REGEX, /EXTRACT)
Here you separate the string of the first line into substrings (in the
previous version you told IDL with (.., ' ',..) that a blank charakter
is the separator, correct?), and the part '[ ' + String(9B) + ']+', /
REGEX, means that the pattern of the ascii file contains not only
blank characters but any combination of blank characters and tabs. Am
I right up to here?
So IDL moves forward starting from one column until the binary code is
different from the code of a blank character or a tab and "knows" that
there is the next column.
I wish you a nice day (for me it's time to leave off work).
Cheers,
Britta
|
|
|
|
comp.lang.idl-pvwave archive
Members
Search
Help
Login
Home
