//  Photovoltaic panel system and DC motor. Construction of graphs: V=f(t),
//  I=f(t), w=f(t), T=f(t) in Scilab. Using vector columns of voltage, 
//  current, etc. to make graphs in EXCEL.
  V = V_PV_xcos.values; 
  I = I_PV_xcos.values; 
  w = w_dc_m.values; 
  T = T_dc_m.values; 
  t = w_dc_m.time; 
f1 = scf(1); plot(t, V); xgrid(); xtitle('','t, [c]','V, [B]')
f1 = scf(2); plot(t, I); xgrid(); xtitle('','t, [c]','I, [A]')
f1 = scf(3); plot(t, w); xgrid(); xtitle('','t, [c]','w, [pad/s]')
f1 = scf(4); plot(t, T); xgrid(); xtitle('','t, [c]','T, [Nm]')
f1 = scf(5); plot(I, V); xgrid(); xtitle('','I, [A]','U,[V]')
