How to find the number of values the equation outputs before repeating the same outputs again?

2 次查看（过去 30 天）
Prayash Thapa
Prayash Thapa 2020-11-20
编辑： Prayash Thapa 2020-11-20
This script is based on implementing Shor's quantum factorization. For the equation 'fncT' whicn is alternative version to mod(), it outputs 4 different values before repeating again, given the parameters 'T = 7' and 'M = 15'. Is it possible to get this number 4 using the fft function and assign it to a variable instead of manually assigning it?
script:
T = 7; % T^P mod(M)
M = 15;
P1 = 127; % 128
P2 = 255; % 258
P3 = 511; % 512
P4 = 1023; % 1024 bits
t = 1:1:sym(P1); % Signal duration/length
fncT = (T.^t) - floor(T.^t/M)*M;
%plot(t,fncT)
%stem(fncT)
A = fftshift(double(fncT));
A = fft(A);
A = fftshift(A);
A_mag = abs(A.*A);
stem(A_mag)
%plot(A_mag);
% GCD
eqn = T^(4/2) + 1; % 4 = no. of time it produces different values before repeating again
eqn1 = T^(4/2) - 1;
[G1] = gcd(eqn,M);
[G2] = gcd(eqn1,M);
disp(['The factors of 15 are ',num2str(G1),' and ', num2str(G2), '.'])
[pks1,pks2,pks3] = findpeaks(A_mag);
x = pks2(1); % Assigning the peaks with a variable
y = pks2(2);
z = pks2(3);

请先登录，再回答此问题。

回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Spline Postprocessing 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by