String Index

[Thomas D. Dean]

I have a string, 87 characters. containing pairs of parens enclosing 
characters.  The number of chars enclosed is not constant.  There are 2 
to 5 pairs of parens.  How do I construct the index to vectorize this?

> n=numel(str)
n =  87
> lp = [1:n](str == "(");
> rp = [1:n](str == ")");
> ## check to see if parens paired and lp < rp
> [lp', rp']
ans =
   38   47
   54   57
   66   73
   85   87

I want to extract values from str using lp and rp

> [ str(lp(1):rp(1));
>   str(lp(2):rp(2));
>   str(lp(3):rp(3));
>   str(lp(4):rp(4)) ]
ans =
(10^20 kg)
(km)
(kg/m^3)
(1)

Tom Dean