Model is underconstrained.
The following variables couldn't be defined:
 * V in component membrane
 * i_Na in component sodium_channel
 * i_Ca in component calcium_channel
 * i_K in component delayed_rectifier_potassium_channel
 * i_K_A in component A_type_potassium_channel
 * i_K_Ca in component calcium_activated_potassium_channel
 * i_L in component leakage_channel
 * alpha_m in component sodium_channel_m_gate
 * beta_m in component sodium_channel_m_gate
 * alpha_h in component sodium_channel_h_gate
 * beta_h in component sodium_channel_h_gate
 * E_Ca in component calcium_channel
 * Ca_e in component parameters
 * alpha_c in component calcium_channel_c_gate
 * beta_c in component calcium_channel_c_gate
 * alpha_n in component delayed_rectifier_potassium_channel_n_gate
 * beta_n in component delayed_rectifier_potassium_channel_n_gate
 * alpha_a in component A_type_potassium_channel_a_gate
 * beta_a in component A_type_potassium_channel_a_gate
 * alpha_h in component A_type_potassium_channel_h_gate
 * beta_h in component A_type_potassium_channel_h_gate
 * g_K_Ca_gate in component calcium_activated_potassium_channel
 * r in component parameters
 * d/dt V in component membrane
 * d/dt m in component sodium_channel_m_gate
 * d/dt h in component sodium_channel_h_gate
 * d/dt c in component calcium_channel_c_gate
 * d/dt n in component delayed_rectifier_potassium_channel_n_gate
 * d/dt a in component A_type_potassium_channel_a_gate
 * d/dt h in component A_type_potassium_channel_h_gate
 * d/dt Ca_i in component parameters