How do I plot a series of points as a collection of 1x2 arrays?

I need to write a function that will plot a series of points that are input as 1x2 arrays separated by commas. I understand that one could simply input all of the x values into one array and all of the y values in to an array (ie. x = [1 4 3 7 2] y = [2 5 1 2 8] plot(x,y,'*'),) however for this problem i am required to input the points as 1x2 arrays separated by collumns like so:

function plotPoints(points);

%insert code here;

end

then in a new script:

plotPoints([1,2] , [2,6] , [8,3] , [6,9])

I have no idea how to go about doing this.

[Sriram Tadavarty]

Ryan, you simply told what you have to do.

plot(x,y,'*')
% The x is the first column of points and y is the second column of points
% So replace with those in above and place it in your function
plot(points(:,1),points(:,2),'*')

For more details of indexing, look here.

[Ryan Begley]

@Sriram Tadavarty I am not sure what you mean, perhaps I should have been more clear or perhaps Im not getting something, each array is its own point like [x,y],[x,y],[x,y]. I can plot the first point by using plot(points(:,1), points(:,2), '*') but in the example I put in my original question it would only plot the point (1,2). I have to plot all of the [x,y] points on a single graph and the function must work for any number of points.

[Sriram Tadavarty]

Ryan,

I am not sure how do you pass such a sequence as inputs? Is it through cell array or a array of size N x 2?

[Ryan Begley]

Sriram,

I am not sure either, all I know is that I have to write a function that will accept an arbitrary number of points as 1x2 arrays [x,y] and plot them. And then i am to demonstrate the use of the function by running

plotPoints([1,2] , [2,6] , [8,3] , [6,9])

I just have no idea how to get it to plot all of the points

[Sindar]

You could use varargin:

function plotPoints(varargin);
    %insert code here;
end

which will produce a cell array as I describe in my answer (in the variable varargin instead of points)

Answer 1

[Sindar]

If you have a cell array of 1x2 arrays like so:

points = {[1,2] , [2,6] , [8,3] , [6,9]};

then you can turn it into a 1x (2N) array, then reshape it to a 2xN array:

points = reshape(cell2mat(points),2,[]);

from there, use Sriram's answer (except the first row is x):

plot(points(1,:),points(2,:),'*')

If you start with a 1x(2N) array, you can remove the cell2mat() call:

points = reshape(points,2,[]);