Why is the x-axis scale different from what I specified in the code?

My problem is about the plot of this code. I attached the text file I have to use;I want to plot the hour(2nd column) on the x-axes and the value(3rd column) on the y-axis. But when I plotted them the scale on x-axis is different from the original data: His range is from 00:00:17 to 00:01:17 instead of 05:00:07 .Why? Could someone help me? Thank you very much

 % YourFilePath = 'C:\Matlab\valori2.txt';
fid = fopen(YourFilePath ,'rt');
Datafile = textscan(fid,'%s%s%s%s%s','Headerlines',2);
    Value = Datafile{3};
    Value = cellfun(@(x) textscan(x,'%s','Delimiter', ' ')',Value ,'UniformOutput',false);
    Y = vertcat(Value{:});
    X = cellfun(@transpose,Y,'UniformOutput',false);
    Z = cellfun(@str2double,X,'UniformOutput',false);
    Value1=cell2mat(Z);
Time (:,1)= Datafile{2};
Time1=cell2mat(Time);
fclose(fid);
plot(Value1,'*')
set(gca,'xticklabel',{Time1})

Answer 1

[Star Strider]

Replace:

set(gca,'xticklabel',{Time1})

with:

xt = get(gca, 'XTick')
set(gca, 'xtick',xt(1:end-1), 'xticklabel',Time1(xt(1:end-1)+1,:))

and it should plot as you want.

[Matteo]

Thanks!It works but now the problem is that the x-axis starts from 00:00:07 but is not correlated with the exact value: everything is shifted. This code work with 31 data but if I will have more data?

[Star Strider]

My pleasure!

The easiest way to do what you want is to use the datetick function.

First, delete (or comment out) these lines:

% plot(Value1,'*')
% xt = get(gca, 'XTick')
% set(gca, 'xtick',xt(1:end-1), 'xticklabel',Time1(xt(1:end-1)+1,:))

then insert these lines in their place:

Time2 = datenum(char(Time), 'HH:MM:SS');
plot(Time2, Value1, '*')
datetick('x', 'MM:SS')
xlabel('Time (min:sec)')

Everything should work as you want it to now.

[Matteo]

Thank you very much!Now it's perfect

[Star Strider]

My pleasure!