向下移动信号

Question

我有一个从0到1的正方形，矩形和锯齿形信号在y轴上创建的信号，我如何将信号向下移动(垂直偏移)，以便信号将在y轴上从-0.5到0.5，并将三角形信号从0.5到1.0更改为-0.5到0.5?

clear all
% SCRIPT BEGINS
t=linspace(0,1,22050)
freq=5%how many times it repeats in 1 sec
A = 1; % amplitude
T = 1/freq; % period of the signal
% square
square = mod(t * A / T, A) > A / 2;
plot(t, square)
title('Square');
% rectangle
l = 0.2; % percentage the signal spends on low value
rectangle = mod(t * A / T, A) > A * l;
figure;
plot(t, rectangle);
title('Rectangle');
% sawtooth
sawtooth = mod(t * A / T, A);
figure;
plot(t, sawtooth);
title('Sawtooth');
% triangle
triangle = (mod(t * A / T, A) > 0.5).*mod(t * A / T, A) + (mod(t * A / T, A) <= 0.5).*(1 - mod(t * A / T, A));
figure;
plot(t, triangle);
title('triangle');

谢谢，我使用的是octave/matlab

Answer 1

function x_new = rescale(x, new_min, new_max)
x_min = min(x);
x_max = max(x);
x_new = new_min + (new_max - new_min) * (x - x_min) / (x_max - x_min);

(顺便说一下，这是非常基本的数学，可以很容易地谷歌)

Answer 2

下面的代码可能对下一个人有帮助

clear all
% SCRIPT BEGINS
t=linspace(0,1,22050);
freq=5; %how many in 1 sec
%t = 0:0.01:1; %time vector
A = 1; % amplitude
T = 1/freq; % period of the signal
vertoffset=0.5;
% square
square = mod(t * A / T, A) > A / 2;
square = square - vertoffset;
plot(t, square)
title('Square');
% rectangle
l = 0.2; % percentage the signal spends on low value
rectangle = mod(t * A / T, A) > A * l;
rectangle = rectangle - vertoffset;
figure;
plot(t, rectangle);
title('Rectangle');
% sawtooth
sawtooth = mod(t * A / T, A);
sawtooth = sawtooth -vertoffset;
figure;
plot(t, sawtooth);
title('Sawtooth');
% triangle
triangle = (mod(t * A / T, A) > 0.5).*mod(t * A / T, A) + (mod(t * A / T, A) <= 0.5).*(1 - mod(t * A / T, A));
triangle = 2*triangle - 1.5;
figure;
plot(t, triangle);
title('triangle');