how to import a file in MATLAB?

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

[Walter Roberson]

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]

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

Answer 1

[Nishitha Ayyalapu]

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');

[Jesus]

I am using MATLAB 7.3.0 (R2006b). I tried what is written in the answer, but it did not work. Appeared the following message: ??? Undefined function or method 'readtable' for input arguments of type 'char'.

[Walter Roberson]

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]

Nishitha Ayyalapu and Walter Roberson, thank you. The TextScan worked perfectly in MatLab (R2006b).

Answer 2

[Gautam PAL]

How to read video file using matlab..?