function [pgx,pgy]=dynam(u,v,f,omega,r)
% function [pgx,pgy]=dynam(u,v,f,omega,r)
% u,v are cm/s, f, r and omega are 1/sec and pg is in m/s**2 
% pgx and pgy are matrices with 4 columns, the first of which is the total 
% pressure gradient, the second of which is that due to i*omega*u, 
% the third from f*v, and the fourth from r*u.
%  r is a vector=Cd*sqrt(abs(u).^2+abs(v).^2)./h
i=sqrt(-1);
pgx=[];
pgy=[];
pgx(:,2)=i*omega*u/100;
pgx(:,3)=f*v/100;
pgx(:,4)=-r.*u/100;
pgx(:,1)=sum(pgx(:,2:4)')';
pgy(:,2)=i*omega*v/100;
pgy(:,3)=-f*u/100;
pgy(:,4)=-r.*v/100;
pgy(:,1)=sum(pgy(:,2:4)')';
