Textscan issues

Once again, I ask your help to sort this out.

I'm trying to use texscan to open a .dat file. I want to ignore the 2 headerlines and I'm only interested in the first 5 columns, and the first two I define has beeing strings.

"location"

"DATA" "HORA" "VMED" "VMAX" "DIR" "TEMP" "PRESS"

14-08-1998 15:30 0.00* 0.00* 270.79* 18.71 1008.57

14-08-1998 16:00 1.49 2.69 272.55 18.43 1008.57

14-08-1998 16:30 1.34 2.09 262.00 18.80 1008.57

14-08-1998 17:00 1.72! 2.39 258.13 18.15 1008.74

14-08-1998 17:30 2.24 2.98 253.91 18.43 1008.74

14-08-1998 18:00 2.91 3.58 261.65 18.52 1008.57

Has you can see, some parameters are followed by a symbol ("*" and "!"), I want Matlab to write them has NaN.

I used the following code:

fid=fopen('/Users/...

v = textscan(fid,'%s %s %f %f %f %*s %*s, 'headerLines',2);

v3=v{3};

v4=v{4};

v5=v{5};

Unfortunately, Something is occuring when I try to create v4 has a double, since matlab only creates 3 empty matices. The only way to create the three matrices is to write:

v = textscan(fid,'%s %s %f %s %f %*s %*s, 'headerLines',2);

But that will create a matrix that I can not use.

On top of all that, a new row is being created at the beggining of the matrices, that does not correspond to the first row from the .dat file. Something like:

0

NaN

1,49

1,34

1,72

2,24

2,91

I really can't understand what is wrong! Please help

Answer 1

[Titus Edelhofer]

Hi,

you are on the right way: read everything as strings:

v = textscan(fid, '%s %s %s %s %s %s %s', 'headerlines', 2);

and then do some manipulation to get the data you are looking for:

v3 = str2double(strrep(strrep(v{3}, '*', ''), '!', ''))

Titus

[Paul]

Thank you Titus, your solution worked beautifully!

Still can't figure out what happened. I believe my code should work!

Answer 2

[Paul]

Well, there's always one more problem!

How can I merge the two first columns into one? say I want to use textscan and tell him to ignore the delimiter between those columns so that I can later use Datenum.

Is it possible?

Thanks

Paul

[Matt Tearle]

If the date and time format is fixed, you can use a fixed-width field specifier: '%16c %s %s %s %s %s'. Then v{1} will be an array of date/time strings.

[Titus Edelhofer]

Hi Paul,

what about strcat(v{1}, v{2})?

Titus