Using ismember with some margin

I asked a question yesterday and I got some good answers but there was a twist to my problem want to use a subset of number to find the index in a bigger set, my smaller set has some margin of error +/- 0.001

eg bigger set BS = [2.33, 4.551, 5.88, 3.98, 4.661, 7.98, 2.331, 9.55]

smaller set SS = [4.55 4.66 7.99]

I want to use the smaller set (SS) to pick the index of its location in the bigger set (BS)

I tried using find, ismembertol but not working well

I will be happy to figure this out

[Jon]

Would be better to preserve the history and responses so far to continue your original post with this as a comment, rather than opening up a new question.

Answer 1

[Walter Roberson]

ismembertol by default uses relative tolerances. To use absolute tolerance with it you need to set the relative portion to 1 and use one of the named options to set the margin to the absolute value you want.

[Walter Roberson]

Sorry details were slightly wrong, see https://www.mathworks.com/help/matlab/ref/ismembertol.html#bup2c1a

Answer 2

[Jon]

You can use ismembertol for this

SSnoisy = SS + randn(size(SS))*0.01
idx = find(ismembertol(BS,SSnoisy,0.05))