How to insert NaNs on an array based on a condition some other array

I have an array

A= [210,210,210,220,220,220,240] 
B= [210,nan,nan,220,nan,nan,240] 
C=[1,2,4,5,7,8,10]

and now i remove NaNs from B

index= find(~isnan(B)) 

and apply this index to B and C

New

B= [210,220,240]

and new

C=[1,5,10]

and now my condition is if

diff(B)<=10 & diff(C)<=4

, i insert NaNs between these indexes in A

so my final A is:

A= [210,210,210,220,nan,nan,240]

Can you please me do this?

[KSSV]

How final A is the result not clear..

[Shambhavi Adhikari]

A is created based on the condition: if diff(B)<=10 & diff(C)<=4, i insert NaNs between these indexes in A.

[madhan ravi]

Why 2 nans?

[Shambhavi Adhikari]

sorry there should be 2 A is: [210,210,210,220, nan,nan,240]

[Jalaj Gambhir]

Yeah, but how are you getting indices 5 & 6 to insert nan in array A, based on this condition? "diff(B)<=10 & diff(C)<=4" Please frame your question in a better way.

Answer 1

[Matt J]

Using group1s from the File Exchange

https://www.mathworks.com/matlabcentral/fileexchange/78008-group1s

index = ~isnan(B);
nangroups = group1s(~index);
diffg = find(diff(B(index))<=10 & diff(C(index))<=4);

mask=any( nangroups==diffg(:) , 1)
A(mask)=nan