How to define 1-bit variable in data dictionary?

FF variable was defined as fixdt(0,1,0) in Data Dictionary.

But it was defined uint8_T after auto-generation.

I want it to be defined as 1-bit variable.

Is there any helpful tip?

Answer 1

[John D'Errico]

MATLAB does not have a true 1-bit data class.

Even a logical, which is clearly a 1 bit thing, thus either true or false, is stored in a byte.

F = false;
T = true(1,10);
whos F T

  Name      Size            Bytes  Class      Attributes

  F         1x1                 1  logical              
  T         1x10               10  logical              

The best you can do is a uint8. At least, unless you write your own code at a deeper level in C. Or, if you wrote your own class, you could use bit manipulation to store information as vectors of single bits of an integer class. That would make it possible to store integer vectors (of single bits) of length 8 (or multiples thereof) as uint8 integers. But it would force you to do the work to access each bit.

[Walter Roberson]

T = true(1,10);
B = typecast(T, 'uint8');
whos T B

  Name      Size            Bytes  Class      Attributes

  B         1x10               10  uint8                
  T         1x10               10  logical              

The fact that both variables show up as 10 bytes proves that logical values are stored as complete bytes