how can I solve the problem where I get the error horizontal dimensions mismatch in octave

Question

I have this octave code

PLAINTXT = "ABC";
UNICODED = [];
BINARY_VALUE = [];

for i = PLAINTXT

  UNICODED = [UNICODED, unicode2native(i, "ISO-8859-1")];
  BINARY_VALUE = [BINARY_VALUE, dec2bin(UNICODED)]
%% stop
endfor

it takes the plain text "ABC" and convert it using ascii encoding system then converting it to binary but I need each to be in a separate set it worked for me when first time when I convert the plain text but it gives me the error "error: horizontal dimensions mismatch (1x7 vs 2x7)" and I don't know what's the problem.

I tried to do as in the code above and I also tried to create another for loop inside the existing on and run the line "BINARY_VALUE = [BINARY_VALUE, dec2bin(UNICODED)]" inside it but it still give me the same result

Answer 1

dec2bin(a) for a scalar a returns a string, and in Octave a string is a 1xN character array.

dec2bin(a) for an array a returns a nxN character array (n being the number of elements in a ).

Hence, in the second iteration when you arrived at BINARY_VALUE = [BINARY_VALUE, dec2bin(UNICODED)] :

• BINARYVALUE was a 1x7 character array after the 1st iteration
• UNICODED is a 1x2 uint8 array
• dec2bin(UNICODED) is hence a 2x7 character array So you are indeed trying to append a 2x7 character array to a 1x7 character array, which is not possible.

I'm not sure what you want at the end, but you could do:

PLAINTXT = "ABC";
UNICODED = [];

for i = PLAINTXT
  UNICODED = [UNICODED, unicode2native(i, "ISO-8859-1")];
endfor
BINARY_VALUE = dec2bin(UNICODED);

Result:

>> UNICODED
UNICODED =

  65  66  67

>> BINARY_VALUE
BINARY_VALUE =

1000001
1000010
1000011