Dear Tim,

thanks for your reply.

I am a bit tired today and the task is a little involved,

so I try to let others work for me

I want to evaluate some mathematical function , which has

arguments βxβ,βyβ,βzβ etc. (think of something like

(x,y,z) -> 5*z*y+x*y**2)

)

at different values for these variables x,y,z.

Actually, Iβve got data, and I am trying to get back that function, or

an

approximation to it, from these data, so itβs actually a (multivariate)

interpolation problem. To do that efficiently, I need to hold

several variable values fixed at some point in time while varying

others.

So, in my example, if I have a Hash like

my_hash={βxβ,[1,1,3,1,5,6],βwβ,[1,2,3,1,4,5],βyβ,[1,1,1,4,4,6]} ,

then these are coordinates where the unknown function is evaluated at.

If, now, the nice and wonderful method I search for, gives me

res={{βxβ=>1,βwβ=>1}=>[0,3],{βxβ=>3,βwβ=>3}=>[2],{βxβ=>5,βwβ=>4}=>[4],{βxβ=>6,

βwβ=>5}=>[5]},

I know that at the 0-th and 3-th measurement point, βxβ and βwβ didnβt

vary,

so, any

change in the function values is due to the change of βyβ from 1 to 4.

Do you have any elegant ideas for that ?

Thank you,

Best regards,

Axel