Time axis explanation required

Hi,

I am recording my 3 seconds voice signal to plot it in a graph. But the time axis in the graph seem strange. I am recording 3 second audio so to my understanding time axis should be from 0-3 but it shows values in [x10^5]. I asked another question here and foud out the code that plots the x axis but I cannot undeerstand how is it being plotted. Here's my code:

fs = 48000;
rec1 = audiorecorder(fs,16,1);
recordblocking(rec1, 3);
myRec1 = getaudiodata(rec1);
time = length(myRec1)/fs
ti = 0:time:(length(myRec1)*time)-time;
axes(handles.orignal)
plot(ti,myRec1)

If I write:

plot(time,myRec1)

it does not plot saying vectors must be of same length. So can anyone explain to me how is this line working

ti = 0:time:(length(myRec1)*time)-time;

I mean like how is it values in [x10^5] and not 0-3 in the x axis?

Answer 1

[David Goodmanson]

Hi Saad,

'time' is (almost) the total length of the time record, so it will not be the spacing when setting up the time array. Try

time = (length(myRec1)-1)/fs
timearray = linspace(0,time,length(myRec1))