Undefined function 'menos3dB' for input arguments of type 'double'

1

Undefined function ‘menos3dB’ for input arguments of type ‘double’.
when i run this prog in matlb 2014
i have this problem:

J_inicial_P=J_vector_P(1);
J_inicial_N=J_vector_N(1);
freq_menos3dB_P(d)=menos3dB( (w_vector/(2pi)),(20log10(abs(J_vector_P)/abs(J_inicial_P))) );
P_com_RCeffects=J_vector_P.efeitosCapacitivos;
N_com_RCeffects=J_vector_N.efeitosCapacitivos;
freq_menos3dB_N_com_efeitosRC(d)=menos3dB( (w_vector/(2pi)),(20log10(abs(N_com_RCeffects)/abs(J_inicial_N))) );
freq_menos3dB_P_com_efeitosRC(d)=menos3dB( (w_vector/(2pi)),(20log10(abs(P_com_RCeffects)/abs(J_inicial_P))) );
rendimento_quantico_vector(d)=(1-exp(-alfa*la));

thank you for th help

2

There’s no CVX here. This is a basic MATLAB question, it seems… and thus this is not the forum to ask it. In particular, menos3dB is not a function CVX knows anything about.