Rotate set of data points

I have a velocity curve which I need to rotate such that the right end remains at the same position where as the left end is rotated to 0 value(y-coordinate). How can I achieve this keeping the curve profile same?

Answer 1

[Mathieu NOE]

hello

see below

the home made solution performs better than built in detrend matlab function (even with 'linear' argument)

%% dummy data
N=1000; % Number of data points
t=[0:1:N-1]/N; 
y = 1.5*(1 - t);
y2=sin(20*t)+y;
y(100:N-100) = y2(100:N-100);

%% solution 1 
ynew1 = detrend(y,'linear');

%% solution 2 (home made)
dy = y(1) - y(end); % if you want start and end point at same Y value (zero or non zero)
yc = linspace(dy,0,numel(y));
ynew2 = y - yc;

plot(t,y,t,ynew1,t,ynew2)
legend('initial data','linear detrend','home made detrend');

[Abhishek Mishra]

Thank you! The second solution worked really good.