changing data based on values

I have a very long string of data, and I want to change each value based on if it is in between certain values in another set of data.

for example, my string of data is 1, 5, 5, 3, 6, 8. I want to change those numbers to 1 if they are between 1 and 3, 2 if they are between 4 and 6, and 3 if they are between 7 and 9. The result should be 1, 2, 2, 1, 2, 3.

In my code, I have the very long string of data that I want to change as X, the range data as Y, and what I want to change it to as Z. The code I came up with (which doesn't work) is:

X(Y(1,:)<X(:,1)<Y(2,:),1) = Z(1,:);

X(Y(2,:)<X(:,1)<Y(3,:),1) = Z(2,:);

X(Y(3,:)<X(:,1)<Y(4,:),1) = Z(3,:);

Etc.

Answer 1

[Image Analyst]

If they're all integers, you can use intlut(). Otherwise you can do it one range at a time by masking

vCopy = v;  % Make copy so you don't change already-changed values, only original values.
mask = v >= 1 & v <= 3;
vCopy(mask) = 1;
mask = v >= 4 & v <= 6;
vCopy(mask) = 2;

and so on.

If there is some method to how you're deciding on the ranges and assignment values, then you can put it into a loop.