Subscript indices must either be real positive integers or logicals

what should i do to not get this error? >> Subscript indices must either be real positive integers or logicals.

[per isakson]

Make sure that the values of sqrt(EbN0) and sqrt(2*EbN0) always are "real positive integers or logicals"

Answer 1

[Walter Roberson]

Remember,

Q(sqrt(EbN0))

means to take the square root of EbN0, and then try to use that square root as an index into the variable Q (which is a scalar.) There is no implied multiplication in MATLAB: if you want

Q .* sqrt(EbN0)

then you have to write that.

[MOHINI MODI]

Thank you very much for helping me. I really appreciate your help. I tried running => Q .* sqrt(EbN0) Still i am getting error >> Subscript indices must either be real positive integers or logicals.

[the cyclist]

It looks like you ran that in the command window, but you did not actually fix line in your script g.m. You need to edit the script before you run it.

Also, you will need to fix the next line

Q .* sqrt(2*EbN0)

Answer 2

[the cyclist]

It looks like you have somehow created a variable with the name sqrt, and you are inadvertently accessing that variable, rather than the sqrt function.

[Walter Roberson]

No, not in this particular case -- but that does certainly happen sometimes!

[the cyclist]

Ah, you are right. I missed the evidence that the workspace didn't have an sqrt variable.

[MOHINI MODI]

Hello Sir, Thank you very much for helping me. sqrt is matlab function i am using and Q is input signal, which is '1'

Answer 3

[MOHINI MODI]

I got the graph, i was expecting. Thank you very much.