Indeed, you can use text
:
y = w(12, 1:col);
ey = e(12, 1:col);
maxerr = y + ey;
minerr = y - ey;
# Add annotations with text(xs, ys, texts)
text(x, maxerr, cellfun('num2str', num2cell(maxerr), 'UniformOutput', false));
text(x, minerr, cellfun('num2str', num2cell(minerr), 'UniformOutput', false));
You may need to adjust the x/y coordinates before passing them to text
.