Array indices must be positive integers or logical values.

e = exp(-SNR_index.^2./2)

compute_the_Q = integral(@(SNR_index) (1/sqrt(2*pi)).*e, SNR_index,Inf,'ArrayValued',true);

exact_P_e_AWGN(SNR_index) = log10(compute_the_Q(sqrt(2*SNR_per_bit_linear(SNR_index)))) ;

Error: Array indices must be positive integers or logical values.

Answer 1

[Torsten]

e = exp(-SNR_index.^2./2)

SNR_index is undefined.

compute_the_Q = integral(@(SNR_index) (1/sqrt(2*pi)).*e, SNR_index,Inf,'ArrayValued',true);

e must be defined as a function of SNR_index:

e = @(SNR_index)exp(-SNR_index.^2./2)

and the function to be integrated must be

@(SNR_index) (1/sqrt(2*pi)).*e(SNR_index)

The lower limit of integration (SNR_index) does not have a value. Maybe you want to define

compute_the_Q = @(xlow) integral(@(SNR_index) (1/sqrt(2*pi)).*e(SNR_index), xlow,Inf);

exact_P_e_AWGN(SNR_index) = log10(compute_the_Q(sqrt(2*SNR_per_bit_linear(SNR_index)))) ;

I don't know what you try to define here. We miss the function SNR_per_bit_linear. If SNR_index has a numerical value, you can just do

exact_P_e_AWGN = log10(compute_the_Q(sqrt(2*SNR_per_bit_linear(SNR_index)))) ;