TRYING to read ASCII data with Mathematica
- To: mathgroup at smc.vnet.net
- Subject: [mg3079] TRYING to read ASCII data with Mathematica
- From: mek at guinan.arl.psu.edu (Mark E. Kotanchek)
- Date: Tue, 30 Jan 1996 02:25:49 -0500
- Organization: Penn State University, Center for Academic Computing
- Sender: owner-wri-mathgroup at wri.com
(Apologies for posting this here rather than *.soft-sys.*; however, I was
hoping for a quick response before I lose the few remaining hairs on my
scalp.)
I have some sizable data files (>40MB) to which I'd like to apply some
subspace processing algorithms. Alas, Mma is being quite adament about not
letting me load the data in reasonable segments and, thereby, avoid running
out of memory. I've been trying various permutations and currently have "the
bible", Shaw&Tigg, Blachman's Quick Refernce, Gray's Mastering Mathematica,
and Gayloard's Programming w/ Mma open on my desk as well as the function
browser. After all that, I have no idea as to why I cannot achive my
objective -- other than to assume some innate malevolence in Mma 2.2 when
running under NEXTSTEP 3.3/Intel.
That said, I have one small (2 MB) file I've been using as a test case and
In[75]:=
!!test15.mts
yields the correct response of a three column by umpteen row ascii response:
97.957191 -1.1539974 -9207.8301
97.967194 -1.1536527 -8654.8857
97.977196 -1.1431384 -3954.8635
97.98719 -1.1343479 -997.78583
97.997192 -1.142449 -4124.4697
:
After some fussing, I discovered that
ReadList[deflectionFile,Real,
RecordLists -> True,
RecordSeparators -> {"\r"}]
will read in the file. Alas, I cannot (nor, do I want to) handle the entire
file in one humongous chunk. Thus, we try the approach...
In[43]:=
strm = OpenRead[deflectionFile]
Read[strm,Real]
Read[strm,Real]
Read[strm,Real]
Read[strm,Real]
Close[strm]
Out[43]=
InputStream[test15.mts, 9]
Out[44]=
97.957191
Out[45]=
-1.1539974
Out[46]=
-9207.8301
Out[47]=
EndOfFile
Out[48]=
test15.mts
along with the error message:
From In[43]:=
Read::readn: Syntax error reading a real number from test15.mts.
Trying various options for RecordSeparators, etc. doesn't seem to do anything
positive. I don't think what I'm trying to should be all that difficult;
however, after fussing for three hours at what should be a trivial task I'm
at wits end. Maybe I've just run into a "feature" of the NEXTSTEP/Intel
version of Mma? (I hear a bug-fix version should be out in August!!)
Thanks for any help,
Mark.
--
Dr. Mark Kotanchek
Signal Processing Dept - 363 ASB
Applied Research Lab/Penn State
P.O. Box 30
State College, PA 16804
e-mail: kotanchek at psu.edu (NeXTmail, MIME-mail)
TEL: (814)863-0682
FAX: (814)863-0753
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