Question: I wish to format each line in a plot so that I can choose given colours for each line. However my x values are in matrix form so I cannot use the `plot(x,y,'b',x,y,'r',...)` style format. Many thanks.

Answer: 
I would recommend doing in a for loop, but maybe there is another way of doing it.

Define your colors in a matrix 

```
cmap = hsv(10) %generate 10 random colors
hold on
for ii=1:10
   plot(x(ii,:),y(ii,:),'color',cmap(ii,:))
end

```

Create `cmap`, as you wish. It needs to be a `nlines X 3` size though.
If you don't need to choose colors as long as they are different, you can `plot(transpose(data))` which will plot every line of data with a different color.