MATLAB: How to plot a single column of values with a linear regression line through it

linear regressionplot

I have a column that I wann plot and have a regression line go through it, How would I do that?

my code so far is:

figure(1)

title('Phase1')

plot(FG)

Best Answer

Here is a simple example (i made it special for you)

N = 20;
x = linspace(0,3,N);
y = 2*x + rand(1,N);
p = polyfit(x,y,1);
y1 = polyval(p,x);
plot(x,y,'.r')
hold on
plot(x,y1,'b')
hold off

Forgot to mention that i have some NAN rows with both columns, would that effect the results?

Then you should do interpolation without NaN

ix = ~isnan(y);             % choose indices that are not NaN
x1 = x(ix);
y1 = y(ix);
p = polyfit(x1,y1,1);
y2 = polyval(p,x1);

Related Solutions

MATLAB: Is there a way to make a plot of a line with different colors

To plot lines as well:

% some data
x = linspace(0,1,100);
y = rand(1,length(x));
tf = y >= 0.5 ;
y2 = y ; y2(~tf) = nan ; 
ph = plot(x,y,'k.-',x,y2,'ro-')
set(ph(2),'linewidth',2)

MATLAB: How to create a function from a script

Is this? Pass the different input arguments (y=drying_rate_1) to the function, as a result you will get the different plots as per y data.

function test1(y)
x = Zeit(~isnan(y));
y = y(~isnan(y));
[p,err] = polyfit(x,y,1);
fit_orig = polyval(p,x);
y_tilde = y - fit_orig;
quants = quantile(y_tilde, 100);
indices = [];
for i = 1:length(y_tilde)
     if((y_tilde(i) > quants(2)) && (y_tilde(i) < quants(end - 1)))
         indices = [indices; i];
     end
end
x_filter = x(indices);
y_filter = y(indices);
[p,err] = polyfit(x_filter,y_filter,1);
y_fit = polyval(p,x_filter);
figure(3);
plot(x_filter, y_filter, x_filter, y_fit)
end

Best Answer

Related Solutions

MATLAB: Is there a way to make a plot of a line with different colors

MATLAB: How to create a function from a script

Related Question