# How to plot 8640 datapoints over a 1 day on a second by second basis (i.e. 86400 seconds)

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Akash Menon on 18 Oct 2018
Answered: Akash Menon on 19 Oct 2018
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Hi there community!
I wanted to build a signal on signal builder on Simulink. I have about 8640 datapoints that were measured over 10 second intervals for 1 day. I want to present the measured data as a continuous signal spread across the whole duration on a second by second basis- meaning the x-axis time range must be from 0-86400 seconds. How do I go about it? As of now I'm only able to plot the data over the 8640 range on the x-axis.
How to I essentially 'stretch' this data to fit the required range? If if only change the x-axis range on signal builder it doesn't work as it doesn't spread the data.
Any help would be great! Many thanks!!

Dennis on 18 Oct 2018
Basically you could just change the x values:
mydata=randi(10,864,1);
x=1:864;
x=x*10;
plot(x,mydata)
However 8640 datapoints will be too many to be displayed correctly.
jonas on 18 Oct 2018
Was the corresponding time not recorded? If not, and you are 100% certain that there is no missing data or significant variation in the sampling frequency, then you can just do as @Dennis suggested and build your own x-vector, although I would suggest using duration or datetime format so that the units are embedded.
x = days(0):seconds(10):days(1)
Akash Menon on 18 Oct 2018
The time was recorded but its like this (10 second intervals): Nope there is no missing data. There are 8640 datapoints for the whole day- one recording taken every 10 seconds.

Akash Menon on 19 Oct 2018
%%Plotting the measured power signals
% Adjusting the x-axis vector (86400 datapoints)
x=1:8640;
x=x*10;
% Plot
plot(x,mydata)
Thanks dennis it worked!Thanks for the tip Jonas- had some issues with implementing that x-scale because the data did not show up. Will have to look more into that about how to fix that. Now I just need to figure out how to import this into signal builder on Simulink.