Eleminating, Finding,and changing the values

I try to solve the problem below with accumarray. And accumarray works for just integer.

I wıll write it more complex. Assume I have two group data, x(y') and z(y) points, and y' is member of y or in the range of y. Now the question how can find z(y)=z(y)- x(y') at y'=y.

For example

for group of calculated data

y'_1= 0.023 is x_1=3.127

y'_2= -0.043 is x_2=2.324

...

y'_i= 0.112 is x_i=1.3418

and

for given data

y_1=-0.047 is z_1=2.432

y_2=0.023 is z_2= 5.231

Y_3=0.05 is z_3=4.548

...

y_n=0.1 is z_n=3.21

i and n are dimension of data or range. I want to find or match y' values in y and then corresponding to y'=~y I want to do z=z-x

in other words if ı get y'_2 value, it is close to y_1 and then I rounded it to y_1(because y' is not match and it is not near y_2). Later I do

z_1-x_2=2.432-2.324=0.088 =z_1 corresponding to point y_1

now for

y_1=-0.047 is z_1=0.088

y_2=0.023 is z_2= 5.231

Y_3=0.05 is z_3=4.548

...

y_n=0.1 is z_n=3.21

[dpb]

Please remove all the "_n" individual values and put your data into the arrays as you actually have it and then give just an example of the input/output values desired. As you have written it, it is just too confusing to try to keep track of which is what...

In your numeric example, it looks like there is an exact match of 0.023; why is that not returned as the match instead?

My initial reaction is that probably your problem can be solved by use of interp1 with the 'nearest' option, but if the above about throwing out exact matches is so you'll have to only use values in the interpolating vector that are not in the ismember result of the target and input vectors.

[ak42]

data file is attached.

find each "y" in "yw" and then do "zw - z" (corresponding y )

if u want plot yw-zw, and after this operation that linear function will deteriorate.

thx

[dpb]

Still ambiguities --

a) (relatively minor point) what is the rule for selection for the repeated values in yw?

and the big hangup--

b) if plot y and z versus index, they're clearly some functional relationship of sorts w/ sequence, but both are multi-valued. Hence, how is one to choose which of multiple values in y is to be the one associated with yw?

Mayhaps if you can explain the end result/objective it would lead to some way to reapproach the problem; as posed I see no particular solution.

[ak42]

In attached file, my aim is explained. I think it could be enough.