我正在尝试绘制适合数据集的函数,但是折线图无法正确连接函数图上的点:(green points are original data, blue circles are points on the function and blue line should be connecting the blue circles.)从开始将毫秒转换为纪元后,问题似乎已经开始迄今为止(x轴)。
%convert millis since epoch to days since 0000
timeVec = zeros(size(x,1), 1);
f = "ddd mmm dd HH:MM:SS yyyy";
for i = 1:size(x,1)
timeTmp = ctime(x(i)/1000);
timeVec(i) = datenum(timeTmp(1:end-1), f);
endfor
%
%convert millis since epoch to days since 0000 (now for the training set examples)
timeVecXX = zeros(size(XX,1), 1);
for i = 1:size(XX,1)
timeTmp = ctime(XX(i)/1000);
timeVecXX(i) = datenum(timeTmp(1:end-1), f);
endfor
%
hold("off");
plot(timeVec, plotFunc(x), '-ob');
datetick("ddd mmm dd");
hold("on");
grid on;
plot(timeVecXX,yy, '.g');
MCVE:
optimTheta = [8.0916e+004; -3.4102e+003; 7.5091e+003];
optimA = 78250000;
mu = [1.5431e+012, 5.8217e-003];
s = [2.4831e+007, 7.1022e-001];
plotFunc = @(p) predict(p,optimTheta,mu,s,optimA);
linZero = -(optimTheta(1)*s(1)-optimTheta(2)*mu(1))/optimTheta(2) %solution for the equation theta0 + theta1*(x-mu(1))/s(1) = 0
x = [1543076107026:(linZero-1543076107026)/100:linZero];
x = x';
%convert millis since epoch to days since 0000
timeVec = zeros(size(x,1), 1);
f = "ddd mmm dd HH:MM:SS yyyy ";
for i = 1:size(x,1)
timeTmp = ctime(x(i)/1000);
timeVec(i) = datenum(timeTmp, f);
endfor
%
hold("on");
plot(timeVec, plotFunc(x), 'o-b');
datetick("ddd mmm dd");
grid on;
xlabel ("Day");
hold("off");
function [y] = predict (X, theta, mu, s, a)
Xtemp = [X, sin((X-a)/(1000*60*60*24/(2*pi)))];
Xtemp = (Xtemp-mu)./s;
Xtemp = [ones(size(Xtemp,1),1), Xtemp];
y = Xtemp*theta;
endfunction
答案 0 :(得分:1)
让它像这样工作:
optimTheta = [8.0916e+004; -3.4102e+003; 7.5091e+003];
optimA = 78250000;
mu = [1.5431e+012, 5.8217e-003];
s = [2.4831e+007, 7.1022e-001];
plotFunc = @(p) predict(p,optimTheta,mu,s,optimA);
linZero = -(optimTheta(1)*s(1)-optimTheta(2)*mu(1))/optimTheta(2); %solution for the equation theta0 + theta1*(x-mu(1))/s(1) = 0
tOffset = 1543076107026;
x = [1543076107026:(linZero-1543076107026)/100:linZero];
x = x';
timeVec = x-tOffset;
xTicks = [-65707026:(24*60*60*1000):539092974];
hold("on");
set(gca, 'xtick', xTicks);
plot(timeVec, plotFunc(x), '-ob');
lTVec = [];
for i=1:size(xTicks,2)
lTVec = [lTVec; strftime("%a %b %d", localtime((xTicks(i)+tOffset)/1000))];
endfor
set(gca, 'xticklabel', lTVec);
grid on;
xlabel ("Day");
hold("off");