what is the meaning of this instruction?

y = -Inf*ones(size(x))

Answer 1

[Azzi Abdelmalek]

x=[1 2;3 4;5 6]
size(x)
ans =
   3     2     %  3 lines and 2 columns
ones(size(x))   % create 3x2 array with 1
ans =
   1     1
   1     1
   1     1
-inf*ones(size(x))
ans =
-Inf  -Inf
-Inf  -Inf
-Inf  -Inf

[lotus]

i understand your example.thank you.but,if the code is like below:

                                                                                            ptotdB = dbp(ptot);

in another file:

                                                                                              function y=dbp(x)
y = -Inf*ones(size(x));
nonzero = x~=0;
y(nonzero) = 10*log10(abs(x(nonzero)));

i don't understand this whole code.can you explain it in the simplest way?