Making a decimal output using three binary inputs

Hello

What tool should I use to make the following pattern in MATLAB?

If A=0, B=0, C=1, the output is equal to 1

If A=1, B=0, C=1, the output is equal to 2

If A=1, B=0, C=0, the output is equal to 3

If A=1, B=1, C=0, the output is equal to 4

If A=0, B=1, C=0, the output is equal to 5

If A=0, B=1, C=1, the output is equal to 6

[Stephen23]

That looks like a Gray-code: https://en.wikipedia.org/wiki/Gray_code

You should be asking about converting Gray-code. But just for fun:

A = cat(3,[0,5;3,4],[1,6;2,0]);
F = @(a,b,c)interpn(A,a+1,b+1,c+1,'nearest');
F(0,0,1)

ans = 1

F(1,0,1)

ans = 2

F(1,0,0)

ans = 3

F(1,1,0)

ans = 4

F(0,1,0)

ans = 5

F(0,1,1)

ans = 6

Answer 1

[John D'Errico]

If you have only 3 bits, so {A,B,C}, then one simple solution is to use a dictionary. Or you could just use a table lookup. For example...

ABC = {[0 0 1],[1 0 1],[1 0 0],[1 1 0],[0 1 0],[0 1 1]};
out = [1 2 3 4 5 6];
dict1 = dictionary(ABC,out)

dict1 = 
  dictionary (cell ⟼ double) with 6 entries:

    {[0 0 1]} ⟼ 1
    {[1 0 1]} ⟼ 2
    {[1 0 0]} ⟼ 3
    {[1 1 0]} ⟼ 4
    {[0 1 0]} ⟼ 5
    {[0 1 1]} ⟼ 6

And now you can use it to lookup any value.

dict1({[1 1 0]})

ans = 4

But more likely, you will have some more length set of inputs. And since this appears to be a gray code of sorts, at least for the present time, you can use bin2gray and gray2bin.

Answer 2

[Arif Hoq]

do it as a function

a=0;
b=1;
c=1;
out=make_decision(a,b,c)

out = 6

function output=make_decision(A,B,C)
if A==0 && B==0 && C==1
    output=1;
elseif A==1 && B==0 && C==1
    output=2;
elseif A==1 && B==0 && C==0
    output=3;
elseif A==1 && B==1 && C==0
    output=4;
elseif A==0 && B==1 && C==0
    output=5;
elseif A==0 && B==1 && C==1
    output=6;
end
end

[reza hakimi]

How to implement this code in Simulink?

Can it be implemented with logic circuit elements without coding?

[reza hakimi]

During execution, the following error is displayed. What is the reason?

During execution, the following error is displayed. What is the reason?

Output argument 'output' is not assigned on some execution paths.

[Stephen23]

"Output argument 'output' is not assigned on some execution paths."

Because the output is not defined on all execution paths. Consider A=1, B=1, C=1, is the output defined? (hint: no).

Ergo, if you supply input combinations which do not define an output, then you will get an error.

[Arif Hoq]

Stephen is right. try this

a=1;
b=1;
c=1;
out=make_decision(a,b,c)

out = 0

function output=make_decision(A,B,C)
if A==0 && B==0 && C==1
    output=1;
elseif A==1 && B==0 && C==1
    output=2;
elseif A==1 && B==0 && C==0
    output=3;
elseif A==1 && B==1 && C==0
    output=4;
elseif A==0 && B==1 && C==0
    output=5;
elseif A==0 && B==1 && C==1
    output=6;
else
    output=0;
end
end

If you want to execut it in simulink try it in a Matlab function block