Re: Re: Bug in Import?
- To: mathgroup at smc.vnet.net
- Subject: [mg54805] Re: [mg54761] Re: [mg54739] Bug in Import?
- From: Chris Chiasson <chris.chiasson at gmail.com>
- Date: Wed, 2 Mar 2005 01:26:52 -0500 (EST)
- References: <200503010658.BAA25141@smc.vnet.net>
- Reply-to: Chris Chiasson <chris.chiasson at gmail.com>
- Sender: owner-wri-mathgroup at wolfram.com
Import["test.tsv", "Words"]
On Tue, 1 Mar 2005 01:58:16 -0500 (EST), Christoph Lhotka
<lhotka at astro.univie.ac.at> wrote:
> On Mon, 28 Feb 2005 03:27:49 -0500 (EST)
> Mark Fisher <mark at markfisher.net> wrote:
> > (1) I export a data set that has two identitcal rows.
> > (2) I use "!!" to display the stored file, showing that it contains two
> > identical rows.
> > (3) I import the file, the result of which does *not* have two identical
> > rows: The first row is different from the second row.
> >
> > Export["test.tsv",
> > {{"2005-01-24", "2005-02-14"},
> > { "2005-01-24", "2005-02-14"}}]
> >
> > !!test.tsv -->
> >
> > 2005-01-24 2005-02-14
> > 2005-01-24 2005-02-14
> >
> > Import["test.tsv"] -->
> >
> > {{2005-01-24, 2005-02-14},
> > {2005, -1, -24, 2005, -2, -14}}
> >
> > Surely this is a bug.
> >
> > (I sent this example to support at wolfram.com three weeks ago, but the
> > only response I've received is that it's not a bug. Frankly, I don't
> > think the tech person who responded understood the example.)
> >
> > I am using version 5.1 for Windows.
> >
> > --Mark.
> >
>
> Hi !
>
> I am not sure, if it is a bug, but you are right, it looks strange. If you
> want to have more control over, how data is stored and recieved use the
> functions Write and ReadList :
>
> You open an outputstream with OpenWrite
>
> In[..]:=stream = OpenWrite["test.tsv"]
> Out[..]:=OutputStream[test.tsv, 113]
>
> and write something to the stream with Write (or WriteString, see the help
> browser):
>
> In[..]:=Write[stream,
> {{"2005-01-24", "2005-02-14"}, {"2005-01-24", "2005-02-14"},
> {"2005-01-24", "2005-02-14"}} // TableForm // StandardForm]
> Out[..]:=test.tsv
>
> Instead of Import, you can use ReadList (or Read, to import not the whole
> file):
>
> In[..]:=ReadList["test.tsv", {"Word", "Word"}]
> Out[..]:={{2005-01-24, 2005-02-14}, {2005-01-24, 2005-02-14}, {2005-01-24,
> 2005-02-14}}
>
> (where you can explicitly specify, how the data should be treated
> ("Word","Real","Record",etc...} and the inner structure in form of nested
> lists.
>
> So in your example {"Word","Word"} means 2 colums of type Word, which tells
> Mathematica to import strings into a list of form
> {{word1,word2},{word3,word4},...}
>
> In[..]:=FullForm[%]
> Out[..]:=List[List["2005-01-24", "2005-02-14"], List["2005-01-24",
> "2005-02-14"],
> List["2005-01-24", "2005-02-14"]]
>
> Don't forget to close the output / input stream with Close after use:
> In[..]:=Close[stream]
>
> ...
>
> -- Christoph Lhotka --
> University of Vienna
> Institute for Astronomy
> Tuerkenschanzstr. 17
> 1180 Vienna, Austria
> fon. +43.1.4277.518.41
> mail. lhotka at astro.univie.ac.at
>
>
--
Chris Chiasson
Kettering University
Mechanical Engineering
Graduate Student
1 810 265 3161
- References:
- Re: Bug in Import?
- From: "Christoph Lhotka" <lhotka@astro.univie.ac.at>
- Re: Bug in Import?