How can I plot data from imported tables in app designer?

I have imported an excel file into an app and have selected specific columns which i wish to plot. However, I still recievce "Error using plot Invalid data argument" on the line of the plot.

t = readtable('ForceTime.xlsx', 'Sheet', 1);

% Time
app.UITable.Data = t(42:end,1);
app.UITable.ColumnName = 'Time';
Tnum = table2array(t(42:end,1));

% Force
app.UITable2.Data = t(42:end,13);
app.UITable.ColumName = 'Force';
Fnum = table2array(t(42:end,13));

% Force-Time Plot
plot(app.UIAxes, Fnum, Tnum, 'r-');

Is there anything I am missing or need to change for the plot to work?

Answer 1

[Mario Malic]

Check both Fnum, Tnum, are their values correct? Since you're reading the Excel file, they might be character arrays.