Convert char to table

Hi,

I have a series of coordinates as char type (disp output):

[446 154;445 155;444 156;443 156;442 156]

How can I convert them to table so can be save like this using writetable:

446 154
445 155
444 156
443 156
442 156

Thanks

[Stephen23]

"I have a series of coordinates as char type (disp output)"

Best solution: avoid the indirection of printing numeric data to text and then converting from text back into numeric.

Answer 1

[Walter Roberson]

str2num preferably with restricted

coordinates = '[446 154;445 155;444 156;443 156;442 156]';
C = str2num(coordinates, 'Evaluation', 'restricted')

C = 5×2

446 154 445 155 444 156 443 156 442 156

T = array2table(C, 'VariableNames', {'X', 'Y'})

T = 5×2 table
     X      Y 
    ___    ___

    446    154
    445    155
    444    156
    443    156
    442    156

Answer 2

[Stephen23]

If you already have a character vector and the goal is to print it to file, then avoid the indirection of converting to numeric just so that you can use WRITEMATRIX:

txt = '[446 154;445 155;444 156;443 156;442 156]';
spl = split(replace(txt,["]","["],""),";");
writelines(spl,'test.txt')

Check the file content:

type test.txt

446 154
445 155
444 156
443 156
442 156

Answer 3

[Voss]

If you have a char vector like this,

coordinates = '[446 154;445 155;444 156;443 156;442 156]';
disp(coordinates)

[446 154;445 155;444 156;443 156;442 156]

then one way to get the numbers out is

C = split(coordinates,';');
C = regexp(C,'[\d+-Ee.]+','match');
C = vertcat(C{:})

C = 5×2 cell array
    {'446'}    {'154'}
    {'445'}    {'155'}
    {'444'}    {'156'}
    {'443'}    {'156'}
    {'442'}    {'156'}

Then you can do whatever conversion you need. For instance, converting to a matrix makes sense to me:

M = str2double(C)

M = 5×2

446 154 445 155 444 156 443 156 442 156

in which case you would use writematrix to write it to a file:

filename = 'matrix.csv';
writematrix(M,filename)

% show the file's contents:
type(filename)

446,154
445,155
444,156
443,156
442,156

Of course, you can also convert to a table and use writetable, if you prefer:

T = array2table(M) % a table of numbers

T = 5×2 table
    M1     M2 
    ___    ___

    446    154
    445    155
    444    156
    443    156
    442    156

filename = 'table_of_numbers.csv';
writetable(T,filename)

% show the file's contents:
type(filename)

M1,M2
446,154
445,155
444,156
443,156
442,156

T = cell2table(C) % a table of char vectors

T = 5×2 table
      C1         C2   
    _______    _______

    {'446'}    {'154'}
    {'445'}    {'155'}
    {'444'}    {'156'}
    {'443'}    {'156'}
    {'442'}    {'156'}

filename = 'table_of_chars.csv';
writetable(T,filename)

% show the file's contents:
type(filename)

C1,C2
446,154
445,155
444,156
443,156
442,156