reshape a cell array to be row major

If I load data with textscan() I'll get back a cell array holding the columns of data. For example

fh = fopen('log.txt');
x = textscan(fh, '%s %f');
fclose(fh);

and a file log.txt containing

xyz  1.73
uvw  3.66
srt  4.73
klm  1.14

then x will be populated as

>> x
1×2 cell array
{4×1 cell}    {4×1 double}

and x{2}, for example, returns the four values in column 2.

What I want instead is for x{2} to give me the contents of the 2nd row, not the 2nd column. At the moment I'm using a double loop to create a new cell array, y, containing the data row-major:

n_rows = length(x{1});
n_cols = length(x);
y = cell(n_rows,1);
for r = 1:n_rows
    for c = 1:n_cols
        y{r}{c} = x{c}(r);
    end
end

Is there a cleaner (shorter, more elegant) solution?

Answer 1

[Voss]

Maybe storing the data in a table will end up being more convenient:

t = readtable('log.txt')

t = 4×2 table
     Var1      Var2
    _______    ____

    {'xyz'}    1.73
    {'uvw'}    3.66
    {'srt'}    4.73
    {'klm'}    1.14

t(2,:)

ans = 1×2 table
     Var1      Var2
    _______    ____

    {'uvw'}    3.66

However, to get a cell array like you ask for:

fh = fopen('log.txt');
x = textscan(fh, '%s');
fclose(fh);

x = reshape(x{1},2,[]).';
x(:,2) = cellfun(@str2double,x(:,2),'Uniform',false);
x = num2cell(x,2);

x{2}

ans = 1×2 cell array
    {'uvw'}    {[3.6600]}

x{2}{1}

ans = 'uvw'

Note that this x is not quite the same as your y:

fh = fopen('log.txt');
x = textscan(fh, '%s %f');
fclose(fh);

n_rows = length(x{1});
n_cols = length(x);
y = cell(n_rows,1);
for r = 1:n_rows
    for c = 1:n_cols
        y{r}{c} = x{c}(r);
    end
end

y{2}

ans = 1×2 cell array
    {1×1 cell}    {[3.6600]}

y{2}{1}

ans = 1×1 cell array
    {'uvw'}

y{2}{1}{1}

ans = 'uvw'

Answer 2

[Al Danial]

Your first sentence, "Maybe storing the data in a table will end up being more convenient:" proved to be the key. With that idea I was able to get the simple solution I was after:

y = rows2vars(readtable('log.txt'));
y = y{:,2:end}'; % omit variable names

The y here will need to be indexed as y{r,c} instead of y{r}{c} but that's merely syntax. Thanks for the tip.