cell2table not working!

Hello, I am trying to open a cdf file and save it in a table. I have used cell2table to do that but it just give me the table of cells as shown below in output. I need to read the contents of it. I was wondering if I could get somehelp with this. Thanks

cdf file: https://drive.google.com/file/d/1BZHEewbtvkiWdd_EErnWib-WXb7In2wl/view?usp=drive_link

prog:

files='D:\CDF\';
files = dir('mvn_*.cdf');
num_files = length(files);
data= cell(1, num_files); 
nam=files.name;
for j = 1:numel(files)
    list = fullfile(files(j).folder, files(j).name);
    vars = spdfcdfinfo(list).Variables(:,1);
    data{j} = cell2table(spdfcdfread(list), 'VariableNames', vars);
end

Output:

data = 1×79 table epochtime_mettime_ephemeristime_unixtime_starttime_endtime_deltatime_integeprom_verheadervalidmoderateswp_indmlut_indeff_indatt_indsc_potmagfquat_scquat_msobins_scpos_sc_msobkgdeaddataefluxquality_flagproject_namespacecraft1

21600×1 double21600×1 double21600×1 double21600×1 double21600×1 double21600×1 double21600×1 double21600×1 double21600×1 int1621600×1 int3221600×1 int1621600×1 int1621600×1 int1621600×1 int1621600×1 int1621600×1 int1621600×1 int1621600×1 single21600×3 single21600×4 single21600×4 single21600×1 int1621600×3 single2×64×21600 single2×64×21600 single2×64×21600 single2×64×21600 single21600×1 int16'MAVEN''0'

[Matt J]

Please make it possible for us to run the line,

cell2table(spdfcdfread(list), 'VariableNames', vars);

in isolation. In other words, attach the output of spdfcdfread(list) in a .mat file so we can see what it is and test how cell2table responds to it.

[Sonali]

just_spdfcdf = 1×7 cell 1234567110597×10 single10597×1 double10597×1 double10597×10 single10597×10 single10597×1 single10597×1 single

cell2tabledata = 1×7 table dataepochtime_unixddata_loddata_upflaginfo110597×10 single10597×1 double10597×1 double10597×10 single10597×10 single10597×1 single10597×1 single

[Walter Roberson]

spdfcdfread() is from github, including from irfu-matlab/contrib/nasa_cdf_patch

[Sonali]

yes

Answer 1

[Walter Roberson]

The first 18 results of spdfcdfread() are 21600 x 1 (of various numeric data types)

Then you have a 21600x3 followed by two 21600x4, then a 21600x1 and a 21600x3

After that you have four 2 x 64 x 21600 .

The 21600 x various sizes could concievably be converted into table variables together, but the 2 x 64 x 21600 would need to be reshaped to fit the 21600 x * sizing.

After that you have a big mix of sizes, including character vectors such as 'MAVEN', including numeric scalars, including a series of 64×27×2 single, including 64×9×2 single, including 4×8 char ...

With all those different sizes, you cannot convert to a table.

You will need to assign to a temporary variable, and extract portions of the temporary variable for conversion (possibly reshaping them and splitting them into cells.)

[Sonali]

Okay. I just need to read the contents of this cdf file. What would be a better way of doing this? I only get the cells of dimension of each column, not the data.

[Walter Roberson]

data{j} = cell2struct(spdfcdfread(list), vars, 2);

[Sonali]

I just wanted data in a table. struct2table is nt working.

[Walter Roberson]

temp = cellfun(@(C) {C}, spdfcdfread(list));
data{j} = table(temp{:}, 'VariableNames', vars);