Extract single-digit and double-digit numbers at the same time from a cell array with "regexp"

Hi, I am trying to extract the numbers from the following cell array:

a={'1','3','6-10','11-20'};

If I use regexp, the number 10, 11 and 20 are also split:

b=regexp(a,'[0-9]','match');
b{:}

ans = 1×1 cell array
    {'1'}

ans = 1×1 cell array
    {'3'}

ans = 1×3 cell array
    {'6'}    {'1'}    {'0'}

ans = 1×4 cell array
    {'1'}    {'1'}    {'2'}    {'0'}

I would like to have the number 10, 11 and 20 unsplitted. How to do it, maybe still with regexp?

[Sim]

I found the solution of @Walter Roberson, that I slightly modified (I just removed the option "once" after "match"), but it still holds the minus sign attached to the numbers:

a={'1','3','6-10','11-20'};
b = regexp(a, '(-?\d+(\.\d*)?)|(-?\.\d+)', 'match');
b{:}

ans = 1×1 cell array
    {'1'}

ans = 1×1 cell array
    {'3'}

ans = 1×2 cell array
    {'6'}    {'-10'}

ans = 1×2 cell array
    {'11'}    {'-20'}

[Sim]

Great answers both @Stephen23 and @Les Beckham!! I would accept both obviously!

Answer 1

[Les Beckham]

a={'1','3','6-10','11-20'};
b=regexp(a,'[0-9]+','match'); %<<< add the + to match multiple numeric characters
b{:}

ans = 1×1 cell array
    {'1'}

ans = 1×1 cell array
    {'3'}

ans = 1×2 cell array
    {'6'}    {'10'}

ans = 1×2 cell array
    {'11'}    {'20'}