Changing hierarchy using () [] {}

Items within parentheses or brackets are resolved before doing numerical calculations and the innermost parentheses are resolved first.  Furthermore, any of the pairs () {} or [] can be used.  For example, in the following

Z{I}=+{34/(11+12)}+11;

eq[i].. zZ{I}=l=10*[3+2]**{34/(11+12)}+11-1;

the 11+12 is computed first then the other parentheses or brackets surrounded terms.