Plot Data Vs time

Hallo guys,

I have data vs time from 15:00:00 TO 10:00:00 next day.

I'm trying to plot data vs time but the problem, it starts from 00:00 not from 15:00 and make the rest = 0

check the figure

I want to start from 15 till 00:00 and continue from 00:00 till 05:00

[Andy]

Without seeing the data file I cannot say for certain. Is the data in a Timeseries? I assume the time is just recorded as a HH:MM:SS. You need to include the DD-MM-YYYY part then it should plot correctly.

[Seth Furman]

As @Andy mentioned it is difficult for us to understand the problem without seeing data. Please attach a MAT file with the data and provide the MATLAB commands used to generate the figure above.

[amr ahmed]

in the excel file, i want to plot coloumns A and B which have time and data, the problem that its 24H formate and it started from a day to next day so that the chart is cumulative.

[amr ahmed]

RSSI_Average_NODE1 = readtable('Full_Room_plot.xlsx','Range','B:B'); %load column of RSSI  
Array_Average_NODE1= table2array(RSSI_Average_NODE1);             %convert rssi values to array
TIME_NODE1 = readtable('Full_Room_plot.xlsx','Range','J:J');%load column of RSSI  
Array_Time_NODE1 = table2array(TIME_NODE1); 
Time_formate_NODE1 = days(Array_Time_NODE1);                 %converting step
figure
plot(Time_formate_NODE1,Array_Average_NODE1)                  %plotting time(X-axis) Vs RSSI_Average(Y-axis)
title('NODE1')

I used this code and unfortunately the chart is not correct

Answer 1

[Star Strider]

Try this —

Info = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/727204/Full_Room_plot.xlsx');
Info.Properties.VariableNames = compose('%c','A'+(0:9));
Array_Average_NODE1 = Info.B;
Array_Time_NODE1 = Info.J;
% Time_formate_NODE1 = hour(Array_Time_NODE1); 
Time_formate_NODE1_Shift = hour(dateshift(Array_Time_NODE1, 'start','hour',-22));

figure
plot(Time_formate_NODE1_Shift, Array_Average_NODE1)
grid
xlabel('Time (hours)')
ylabel('Room Data')

The dateshift function can shift the time values to (in this instance) start at a specific time, here subtracting 22 hours from the beginning so that value is now the beginning of the series (hour 0).

Experiment to get different results.

.

[amr ahmed]

it is much better but i need the time in formate HH:MM:SS, to get the whole signal values

[Star Strider]

Try this —

Info = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/727204/Full_Room_plot.xlsx');
Info.Properties.VariableNames = compose('%c','A'+(0:9));
Array_Average_NODE1 = Info.B;
Array_Time_NODE1 = Info.J;
% Time_formate_NODE1 = hour(Array_Time_NODE1); 
Time_formate_NODE1_Shift = hour(dateshift(Array_Time_NODE1, 'start','hour',-hour(Array_Time_NODE1(1))));

figure
plot(Time_formate_NODE1_Shift, Array_Average_NODE1)
grid
xlabel('Time (hours)')
ylabel('Room Data')
xtickformat('%2d:00:00')
set(gca, 'XTickLabelRotation',30)

% xt = get(gca, 'XTick');                                                     % Without 'xtickformat'
% set(gca, 'XtickLabel',compose('%02d:00:00',xt), 'XTickLabelRotation',30)    % Without 'xtickformat'

The ‘Time_formate_NODE1_Shift’ vector are no longer datetime values, so this is the best outcome.

Make appropriate changes to get different results.

.