function plotbasisgrid(P_B)
% function plotbasisgrid(P_B)
%
% input: P_B=[b_1(1) b_2(1); b_1(2) b_2(2)]
%             where b_1 and b_2 are basis vectors
%
% output: plots basis vectors and
%               grid of vectors with integer coordinates between -2 and 2
%

%figure
%hold on

plotvector(P_B(:,1),2)
plotvector(P_B(:,2),2)


for j1=(-2):1:2
for j2=(-2):1:2

gridvec=j1*P_B(:,1)+j2*P_B(:,2);

scatter(gridvec(1,1),gridvec(2,1),'r');


end
end


