How change x axis scale from array values into time?

Hai, i have this code, and i woud like make x axis above graph, like x axis of picture bottom. Sin graph is correct in time samples from bottom picture, but i want make signal with zeros, until f.e. 1*10^7 s., then sinusoid. How to change x axis scale from index values into time samples?

code:

clear all; close all; f = 14E6; % Input Signal Frequency T=1/f; fs=1000e6; dt=1/fs; Nper=10; % period tmax=Nper*T; lambda=3e8/f; %bangos ilgis metrais d=lambda/2 %atstumas tarp elementu t = [0:dt:tmax];%sinusinio signalo trukme x1=zeros(1,100); s1 = sin(2*pi*f*t); x1(1,100:814)=s1; figure(1); subplot(2,1,1); %x1 = awgn(x1,20); plot (x1); grid ('on'); subplot(2,1,2); plot(t,s1); grid ('on');

Thank for the tips, and help.

Answer 1

[Rick Rosson]

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