How to merge and slice arrays of different sizes?

Say I have one aray called `ydata` which has dimension 1x24000 and I want to slice a part of this array, say from index 2:3000 and merge it with another array we shall call `udata` which is itself 1x24000. How might I slice the bit I want from `ydata` and then merge it with `udata` if that makes sense?

I suppose what it boils down to is this:

1. we have 2 arrays with the same dimension
2. I want to slice a part from array 1 and merge it with array 2

Is this possible?

[Chris]

What do you mean by "merge"? Are you trying to overwrite the values in the udata array? Add them? Do something else?

[HC98]

Slice and merge with the second array, i.e., add it on

[Chris]

Are they double arrays? String arrays? chars? Do you want to add a second row to the array containing that slice?

u = randi(10,1,5);
y = randi(10,1,5);
u(2,2:4) = y(1,2:4)

u = 2×5

8 1 2 7 5 0 10 8 9 0

Answer 1

[cdawg]

I'm not totally sure if you mean add it as a new row to the second array or append the first array to the end of the second.

If you want to just append part of it to the end you can do this:

ydata = [2 1 9 10 11];
udata = [1 2 3 4 5];

newArray = [udata ydata(2:4)] % append indices 2 through 4 to the end of udata

newArray = 1×8

1 2 3 4 5 1 9 10

If you want to append part of ydata to a new row of udata, they need to have the same number of columns:

newArray = [udata(2:4); ydata(2:4)]

newArray = 2×3

2 3 4 1 9 10

Hope this helps

Answer 2

[Chris]

Perhaps you'd be better off with a cell array.

ydata = randi(9,1,8)

ydata = 1×8

7 7 8 4 1 9 1 3

ydata = num2cell(ydata)

ydata = 1×8 cell array
    {[7]}    {[7]}    {[8]}    {[4]}    {[1]}    {[9]}    {[1]}    {[3]}

udata = num2cell(randi(9,1,8))

udata = 1×8 cell array
    {[7]}    {[2]}    {[7]}    {[2]}    {[1]}    {[3]}    {[8]}    {[7]}

udata(2,2:6) = ydata(1,2:6)

udata = 2×8 cell array
    {[       7]}    {[2]}    {[7]}    {[2]}    {[1]}    {[3]}    {[       8]}    {[       7]}
    {0×0 double}    {[7]}    {[8]}    {[4]}    {[1]}    {[9]}    {0×0 double}    {0×0 double}