%%%verification of polyphase structures using trig
clc;clear all;close all

fs = 1e8;
t = (0:1:1e2)'/fs;
% f = 20e6;
% s = sin(2*pi*f*t);
s = triang(1e2-1);
s = [zeros(1,10) s' zeros(1,10)]';
N = length(s);
ts = (0:1:N-1)'/fs;
%%%
s_r1 = [0 s(1:end-1,1)']';
[s2,s2_mean] = MeanIntp(s,s_r1);

s_intp2 = zeros(2*N,1);
s_intp2(1:2:2*N) = s2_mean;
s_intp2(2:2:2*N) = s2;
t_intp2 = (0:1:2*N-1)'/fs/2;
%%%
s2_r1 = [0 s2(1:end-1,1)']';

[s4_4,s4_3] = MeanIntp(s2,s2_mean);
[s4_2,s4_1] = MeanIntp(s2_mean,s2_r1);

s_intp4 = zeros(4*N,1);
s_intp4(1:4:4*N) = s4_1;
s_intp4(2:4:4*N) = s4_2;
s_intp4(3:4:4*N) = s4_3;
s_intp4(4:4:4*N) = s4_4;

t_intp4 = (0:1:4*N-1)'/fs/4;


figure('Units','normalized','Position',[0.000390625,0.517361111111111,0.49921875,0.422916666666667]);
plot(ts,s,t_intp2,s_intp2)
grid on
% xlim([0.58 0.62]*1e-6)
% 
% 
figure('Units','normalized','Position',[0.500390625,0.517361111111111,0.49921875,0.422916666666667]);
plot(t_intp4,s_intp4)
grid on
% xlim([0.58 0.62]*1e-6)