how to set a plot to start at zero

I am working with gait data and have resampled 1 gait cycle (~120 data points) in to 100 using

[c,d] = size(RawData);

GC_Percent = resample (RawData,100,c);

This seems to work fine but when i plot the data it starts at 1% is there a way to change the output the the first value is plotted at 0 on the y axis?

Answer 1

[KSSV]

Subtract the minimum value (1%) from the data and then plot....

[WellsJ]

apologies if i've misunderstood but that has shifted the data down to the x axis (obviously) i'm looking to shift it left on to the y axis.

Thank you

[KSSV]

Try subtracting the minimum y value from y data.

Answer 2

[Jan]

The output in the plot does not depend on the Y values, but on the provided x values:

y = rand(10, 10);
subplot(1,2,1);
plot(y)
subplot(1,2,2)
plot(0:9, y)

You posted the code for creating y, but the actual problem appears in the command for plotting, which you did not show.

By the way: resample applied an "antialiasing FIR lowpass filter". It is questionable if tis is really wanted for the analysis of the motion. I prefer a linear interpolation and have written for the same problem: FEX: ScaleTime

Yi = ScaleTime(Y, 100)

Are you sure that you want 100 time steps? Usually 101 steps are used in motion analysis to represent 100 intervals of 1%.

[WellsJ]

Thank you this is actually the "step" i used (can't beat a gait pun). And yes upon adjusting for the offset on the x axis i changed it to 101 steps.

[WellsJ]

in regards to your other point about the use of

resample

I had initially tried to use interp1 but i never managed to get the syntax correct. If you have the opportunity i'd be really grateful for any advice.

Thank you

[Jan]

I've posted a link to the code already, which solves the problem much faster than interp1. But if you prefer this function:

sY = size(Y, 1);
Yi = interp1(1:sY, Y, linspace(1, sY, 101));

[husnir nasyuha]

Hi, may I know what is Y in this code refer to?