how to import a file in MATLAB?

2 次查看（过去 30 天）
Jesus
Jesus 2013-10-3
回答： Gautam PAL 2013-10-16
I want to import a file (.dat or txt) in MATLAB, which contains numbers and NaN in some columns.
My file looks like this:
Name:
Day: 5/07/21998
UT LT hpp fpH SSP EF GG
0.0808 21.0808 227 - - N
0.1732 21.1732 300 4.7 340 - N
0.2533 21.2533 237 4.6 335 - N
0.3333 21.3333 249 - - N
0.4233 21.4233 251 - - N
0.5033 21.5033 244 4.6 328 - N
0.5833 21.5833 256 - - N
0.6733 21.6733 253 4.7 330 - N
  2 个评论
Walter Roberson
Walter Roberson 2013-10-3
Do any values before the UT heading need to be imported? Which of the columns do you want read in? For example the EF column is shown here as always "-", but should that be skipped or read in? In the SSF column, should the blank entries be important as 0 or as NaN or should the column be imported as string without numeric interpretation?
Jesus
Jesus 2013-10-3
编辑：Jesus 2013-10-3
1- No. The data before UT does not need to be imported.
2- I'd like to read all the columns (UT, LT, hpp, fph, SSP, EF, GG). UT( float), LT (float), hpp(float), fpH(float), SSP(float), EF(string or char), GG (string or char).
Note: each column is separated by tab

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Nishitha Ayyalapu
Nishitha Ayyalapu 2013-10-14
编辑：Nishitha Ayyalapu 2013-10-14
You could use
readtable
Lets say your data is in testdata.txt then following would create a table "T" with 7 columns, 8 rows and also saves column headers (UT, LT, hpp..etc).
to access UT column you would do
T.UT
However, with this approach fpH to hold all numeric data as float, the '-' entries are treated as empty and are recorded as nan.
T = readtable('testdata.txt','Delimiter','\t','HeaderLines',3,...
'TreatAsEmpty','-','Format','%f%f%f%f%f%s%s');
If fpH has to hold '-' entries and also the numeric data, fpH can be read as a string. But all the numeric data is also recorded as string
T = readtable('testdata.txt','Delimiter','\t','HeaderLines',3,...
'Format','%f%f%f%s%f%s%s');
  3 个评论
显示 1更早的评论
Walter Roberson
Walter Roberson 2013-10-15
编辑：Walter Roberson 2013-10-15
readtable() is very new. You can convert Nishitha's code as:
fid = fopen('testdata.txt', 'r');
T = textscan(fid, '%f%f%f%f%f%s%s', 'Delimiter','\t','HeaderLines',3,...
'TreatAsEmpty','-');
fclose(fid);
then the various columns are T{1}, T{2} and so on. But HeaderLines is perhaps 5 rather than 3.
Jesus
Jesus 2013-10-15
Nishitha Ayyalapu and Walter Roberson, thank you. The TextScan worked perfectly in MatLab (R2006b).

请先登录，再进行评论。

更多回答（1 个）

Gautam PAL
Gautam PAL 2013-10-16
How to read video file using matlab..?

类别

在 Help Center 和 File Exchange 中查找有关 Large Files and Big Data 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by