I have a data which class is char, containing n rows and 4 columns. I wanna extract first column.

a=

 N334      4261461.0645      2661117.6797      3918916.0472

 N352       4266205.852        2659683.96      3914798.2885

 N404      4258400.8221       2662966.354       3920634.872

 %class=char

%I wanna extract first column, (N334 N352 N404) from this char data.

%also every rows and columns would include numbers.

b=

334 4261461.0645 2661117.6797 3918916.0472

352 4266205.852 2659683.96 3914798.2885

404 4258400.8221 2662966.354 3920634.872

class=char %in this case solution is same to above data or different codes available?

[Jan]

No, the shown variable "a" does not have the type char and 4 columns. It looks more like a cell string. Please post the code, which creates the data you have. Otherwise important details of the question must be guessed. Please note that "class=char" is cryptic.

Answer 1

[Andrei Bobrov]

a = regexp(cellstr(a),'\d*(\.\d*)?','match');
b = str2double(cat(1,a{:}));

Answer 2

[Jan]

With some bold guessing:

a = {'N334'      '4261461.0645'     '2661117.6797'      '3918916.0472'; ...
     'N352'       '4266205.852'       '2659683.96'      '3914798.2885'; ...
     'N404'      '4258400.8221'      '2662966.354'       '3920634.872'}
a = strrep(a, 'N', '');
s = sprintf('%s*', a{:});
d = reshape(sscanf('%g*'), size(a));

[sermet]

I'm correcting the question and I asked again.