how to find negative and positive number from a string?

Question

I've a set of chemical reactions, and I need to read only the first number of each chemical. For example, I've a string as

reaction = '-1.0CdCl2(aq)  1.0Cd++  2.0Cl-';

I want the find -1.0 of CdCl2(aq), 1.0 of Cd++, and 2.0 of Cl-.

Answer 1

textscan works here (assuming white-space delimiting the reactants):

>> C = textscan(reaction,'%f%s')
C = 
    [3x1 double]    {3x1 cell}
>> C{1}' %' decimals not shown
ans =
    -1     1     2
>> C{2}
ans = 
    'CdCl2(aq)'
    'Cd++'
    'Cl-'

Also assuming reaction starts with a number.