How to rearrange this dataset?

Hello,

I would like to make a contour plot (i.e., contourf(x,y,z)), where x is year-day, y is depth, and z is data). However, the shape of my dataset currently looks like:

x y z

21 0 0.1

21 10 0.23

21 20 0.32

22 0 0.31

22 10 0.14

22 20 0.42

23 0 0.23

23 10 0.43

23 20 0.38

I understand that to make a contour plot, z should be looking like this:

0.1 0.31 0.23

0.23 0.14 0.43

0.32 0.42 0.38

How to arrange data like above one? Or is there any other way to make a contour plot with what I have?

Thanks

Answer 1

[the cyclist]

There may have been slicker ways to do this further "upstream" in your code, but now you could just do

>> z = reshape(z,3,3);

[Hyewon]

Thanks.

To RESHAPE the number of elements must not change.

This message appears. Do you have any idea?

[the cyclist]

Isn't z a 9x1 vector? I assumed that from the way you wrote it.

[Hyewon]

Oh, that worked. Thanks so much!

[Hyewon]

What if x and y are not uniform?

x y z

21 0

21 10

21 15

21 30

22 0

22 10

22 20

23 0

23 10

23 13

like this?

[the cyclist]

This is difficult to answer in general. You will typically want to use a command like meshgrid() to created the (x,y) framework of grid points, then assign z with the same shape as that output. See

doc meshgrid

for some tips.