I am working on a set of datapoints like so:
x = [270 280 290 300 310 320 330 340 350 0 10 20 30 40 50 60 70 80 90]
y = [10000 9000 5500 2500 900 2500 5500 9000 10000 9000 5500 2500 900 2500 5500 9000 10000]
I have defined a sine^2(x) function with a phase shift of 45 degree, for fitting along these data points, because my data points are shifted that way.
I define x1 = 1:numel(x);
Using set(gca,’xTick’,x1,’XTickLabel’,x), I know that I can display in the x-axis order 270,…,0,…,90, without which I would get them in the x-axis order 0…90,…,270,…,350.
But, how do I apply that order for the fitting function itself? That doesn’t seem to work.
I attach the code for your reference.

function[]=plotdata(filename)
S = load(filename);
C = struct2cell(S);
M = cell2mat(C);
x = M(:,1)
y = M(:,end)
x1 = 1:numel(x);
mean(y)
xlocs = [270 0 90]
%freq = 1/(2*mean(diff(xlocs))) %diff(xlocs)
freq = 1 / (2*mean(diff(xlocs)))
[lb,ub] = bounds(y)
fcn = @(b,x)b(1).*cos(2*pi*x*b(2)+b(3)+(pi/4)).^2+b(4)
B0 = [ub-lb; freq; 0; lb]
myfun = @(b)norm(fcn(b,x) – y);
[B,fv] = fminsearch(myfun,B0)
xv = linspace(max(x),min(x),1000); %A smoother x vector
figure
plot(x, y, ‘*’, ‘DisplayName’,’Data’)
hold on
plot(xv, fcn(B,xv), ‘-r’, ‘DisplayName’,’Regression’)
hold off
%set(gca,’xTick’,x1,’XTickLabel’,x)
endI am working on a set of datapoints like so:
x = [270 280 290 300 310 320 330 340 350 0 10 20 30 40 50 60 70 80 90]
y = [10000 9000 5500 2500 900 2500 5500 9000 10000 9000 5500 2500 900 2500 5500 9000 10000]
I have defined a sine^2(x) function with a phase shift of 45 degree, for fitting along these data points, because my data points are shifted that way.
I define x1 = 1:numel(x);
Using set(gca,’xTick’,x1,’XTickLabel’,x), I know that I can display in the x-axis order 270,…,0,…,90, without which I would get them in the x-axis order 0…90,…,270,…,350.
But, how do I apply that order for the fitting function itself? That doesn’t seem to work.
I attach the code for your reference.

function[]=plotdata(filename)
S = load(filename);
C = struct2cell(S);
M = cell2mat(C);
x = M(:,1)
y = M(:,end)
x1 = 1:numel(x);
mean(y)
xlocs = [270 0 90]
%freq = 1/(2*mean(diff(xlocs))) %diff(xlocs)
freq = 1 / (2*mean(diff(xlocs)))
[lb,ub] = bounds(y)
fcn = @(b,x)b(1).*cos(2*pi*x*b(2)+b(3)+(pi/4)).^2+b(4)
B0 = [ub-lb; freq; 0; lb]
myfun = @(b)norm(fcn(b,x) – y);
[B,fv] = fminsearch(myfun,B0)
xv = linspace(max(x),min(x),1000); %A smoother x vector
figure
plot(x, y, ‘*’, ‘DisplayName’,’Data’)
hold on
plot(xv, fcn(B,xv), ‘-r’, ‘DisplayName’,’Regression’)
hold off
%set(gca,’xTick’,x1,’XTickLabel’,x)
end I am working on a set of datapoints like so:
x = [270 280 290 300 310 320 330 340 350 0 10 20 30 40 50 60 70 80 90]
y = [10000 9000 5500 2500 900 2500 5500 9000 10000 9000 5500 2500 900 2500 5500 9000 10000]
I have defined a sine^2(x) function with a phase shift of 45 degree, for fitting along these data points, because my data points are shifted that way.
I define x1 = 1:numel(x);
Using set(gca,’xTick’,x1,’XTickLabel’,x), I know that I can display in the x-axis order 270,…,0,…,90, without which I would get them in the x-axis order 0…90,…,270,…,350.
But, how do I apply that order for the fitting function itself? That doesn’t seem to work.
I attach the code for your reference.

function[]=plotdata(filename)
S = load(filename);
C = struct2cell(S);
M = cell2mat(C);
x = M(:,1)
y = M(:,end)
x1 = 1:numel(x);
mean(y)
xlocs = [270 0 90]
%freq = 1/(2*mean(diff(xlocs))) %diff(xlocs)
freq = 1 / (2*mean(diff(xlocs)))
[lb,ub] = bounds(y)
fcn = @(b,x)b(1).*cos(2*pi*x*b(2)+b(3)+(pi/4)).^2+b(4)
B0 = [ub-lb; freq; 0; lb]
myfun = @(b)norm(fcn(b,x) – y);
[B,fv] = fminsearch(myfun,B0)
xv = linspace(max(x),min(x),1000); %A smoother x vector
figure
plot(x, y, ‘*’, ‘DisplayName’,’Data’)
hold on
plot(xv, fcn(B,xv), ‘-r’, ‘DisplayName’,’Regression’)
hold off
%set(gca,’xTick’,x1,’XTickLabel’,x)
end curve fitting, reordering, plot MATLAB Answers — New Questions

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