MATLAB: The error ” Assignment has more non-singleton rhs dimensions than non-singleton subscripts” when happen

communicationcommunications blocksetMATLAB

K=128;
N=4;
QPSk_Set=[1 -1 1j  -1j];
Phase_Set=[1 -1];
MAX_SYMBOLS=1e5;
PAPR_Orignal=zeros(1,MAX_SYMBOLS);
PAPR_SLM=zeros(1,MAX_SYMBOLS);
X=zeros(N,K);
Index=zeros(N,K);
for nSymbol=1:MAXSYMBOLS
  Index(1,:)=randi(1,K,length(QPSK_Set))=1;
  Index(2:N,:)=randi(N-1,K，length(Phase_Set))+1;
end
the error  ' Index(1,:)=randi(1,length(QPSk_Set))+1 '
I need help ! How do i solve it??

Best Answer

There is an orphaned "= 1" in the line:
Index(1,:)=randi(1,K,length(QPSK_Set))=1;
%                                     ^^
MAXSYMBOLS is not defined, but MAX_SYMBOLS is.
In
Index(2:N,:)=randi(N-1,K，length(Phase_Set))+1;
%                       ^^
there is an unknown character. Simoply delete it and retype the comma.
QPSK_Set is not defined also, but only QPSk_Set with an lower-case "k".
After fixing these typos, the line is failing:
Index(1,:)=randi(1,K,length(QPSk_Set))
because the left-hand-side is [1 x 128] and the right-hand-side [128 x 4]. Due to the lack of comments it is not clear, what the code should do, so all I can do is guessing:
Index(1,:)=randi(length(QPSK_Set), 1, K)
Finally you overwrite Index(1,:) in each iteration. This is not useful.
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