Thread Subject:

Matlab errors

hello everyone I'm new here and I was wandering if you could help me with this program...

My code:

function o = convertSingletoOctal(bs)
F2=zeros(1,23);
e2=zeros(1,8);
for i=10:32
F2(i-9)=bs(i);
end
for i=2:9
e2(i-1)=bs(i);
end
[E8,F8,e8]=Convert2to8Exp(F2,e2);%Calling the function Convert2to8Exp
t=bs(1);
if t == 1
o=disp(['o = - ', num2str(E8),'.',num2str(F8),' * 8^',num2str(e8)]);
elseif t == 0
o=disp(['o = + ', num2str(E8),'.',num2str(F8),' * 8^',num2str(e8)]);
end
end









Convert2to8Exp function=

function [E8,F8,e8]=Convert2to8Exp(F2,e2)
[E,F,e]= ShiftBinary(F2,e2);%Calling the function
%Converting the integral part
r=e2-e;
if(r==0)
    E=[0 0 E];
elseif(r==1)
    E=[0 E];
end
E8=(E(1)*2^2)+(E(2)*2)+E(3);

%Converting the fractional part
k =length(F);
re=rem(k,3);
if(re==1)
    F=[F 0 0];
elseif(re==2)
    F=[F 0];
end
k1 = length(F);
o = k1/3;%number of octal triplets
F8=zeros(1,8);
for i=1:o
F8(i)=F(3*i-2)*2^2+F(3*i-1)*2+F(3*i);
end
%Computing the exponent
e8=e/3;
end






Shift Binary function:

function [E , F, e] = ShiftBinary(F2, e2)
q = floor (e2/3);
r = rem (e2,3);
if (r==1)
    E= [1 F2(1)];
    F= F2(2:(length(F2)));
elseif (r==2)
    E= [1 F2(1) F2(2)];
    F= F2(3:(length(F2)));
elseif (r==0)
    E= 1;
    F= F2(1:length(F2));
end
e = 3 * q;
end












The error:

Error in ==> ShiftBinary at 7
q = floor (e2/3);

??? Output argument "E" (and maybe others) not assigned during call to
"C:\Users\ABDO\Documents\MATLAB\ShiftBinary.m>ShiftBinary".

Error in ==> Convert2to8Exp at 8
[E,F,e]= ShiftBinary(F2,e2);%Calling the function

Error in ==> convertSingletoOctal at 14
[E8,F8,e8]=Convert2to8Exp(F2,e2);%Calling the function Convert2to8Exp





Thank you for your help

You should learn how to use the debugger. If you knew how to do that
you could progress through your program one line at a time. Then
you'd notice that none of your if blocks was ever entered, thus E and
F were never assigned. They need to be because you return them.
Apparently the remainder of e2 and 3 is never an integer. e2 if
probably a floating point number. In that case, you need to read and
understand the FAQ: http://matlab.wikia.com/wiki/FAQ#Why_is_0.3_-_0.2_-_0.1_.28or_similar.29_not_equal_to_zero.3F

Again, I HIGHLY recommend that you learn how to use the debugger.
Everyone here who is successful with MATLAB has learned how in a short
time.

"Abdo " <aea11@aub.edu.lb> wrote in message <jk35l5$sc0$1@newscl01ah.mathworks.com>...
> ........
> function [E , F, e] = ShiftBinary(F2, e2)
> q = floor (e2/3);
> r = rem (e2,3);
> if (r==1)
> E= [1 F2(1)];
> F= F2(2:(length(F2)));
> elseif (r==2)
> E= [1 F2(1) F2(2)];
> F= F2(3:(length(F2)));
> elseif (r==0)
> E= 1;
> F= F2(1:length(F2));
> end
> e = 3 * q;
> end
> ........
- - - - - - - - -
  There appears to be a serious misunderstanding about bit strings in this code. In the 'convertSingletoOctal' function eight elements from 'bs' (apparently standing for a "bit string") are copied into the eight-element row vector 'e2'. Then 'e2' is passed over to 'Convert2to8Exp' and unchanged on over to 'ShiftBinary'. At that point, as nearly as I can make out, 'e2' is suddenly regarded as a single numerical quantity for which it is to be decided what its remainder is after being divided by 3 in preparation for conversion to an octal exponent.

  The immediate cause of the error message is that an 'if' statement, as in the line "if (r==1)", when faced with a multiple-element logical row vector will insist that all of these be true to satisfy the 'if' condition. Since none of the three conditions (r==1), (r==2), and (r==0) were apparently true for all eight elements simultaneously, then none of the needed actions in returning E, and F were carried out. Hence the message.

  However far more serious than this is the treatment of the string of eight bits as a single numerical quantity. This code will require some extensive overhaul for it to function properly, in my opinion.

Roger Stafford

On Mar 17, 7:10 pm, "Abdo " <ae...@aub.edu.lb> wrote:
> hello everyone I'm new here and I was wandering if you could help me with this program...
>
> My code:
>
> function o = convertSingletoOctal(bs)
> F2=zeros(1,23);
> e2=zeros(1,8);
> for i=10:32
> F2(i-9)=bs(i);
> end
> for i=2:9
> e2(i-1)=bs(i);
> end
> [E8,F8,e8]=Convert2to8Exp(F2,e2);%Calling the function Convert2to8Exp
> t=bs(1);
> if t == 1
> o=disp(['o = - ', num2str(E8),'.',num2str(F8),' * 8^',num2str(e8)]);
> elseif t == 0
> o=disp(['o = + ', num2str(E8),'.',num2str(F8),' * 8^',num2str(e8)]);
> end
> end
>
> Convert2to8Exp function=
>
> function [E8,F8,e8]=Convert2to8Exp(F2,e2)
> [E,F,e]= ShiftBinary(F2,e2);%Calling the function
> %Converting the integral part
> r=e2-e;
> if(r==0)
>     E=[0 0 E];
> elseif(r==1)
>     E=[0 E];
> end
> E8=(E(1)*2^2)+(E(2)*2)+E(3);
>
> %Converting the fractional part
> k =length(F);
> re=rem(k,3);
> if(re==1)
>     F=[F 0 0];
> elseif(re==2)
>     F=[F 0];
> end
> k1 = length(F);
> o = k1/3;%number of octal triplets
> F8=zeros(1,8);
> for i=1:o
> F8(i)=F(3*i-2)*2^2+F(3*i-1)*2+F(3*i);
> end
> %Computing the exponent
> e8=e/3;
> end
>
> Shift Binary function:
>
> function [E , F, e] = ShiftBinary(F2, e2)
> q = floor (e2/3);
> r = rem (e2,3);
> if (r==1)
>     E= [1 F2(1)];
>     F= F2(2:(length(F2)));
> elseif (r==2)
>     E= [1 F2(1) F2(2)];
>     F= F2(3:(length(F2)));
> elseif (r==0)
>     E= 1;
>     F= F2(1:length(F2));
> end
> e = 3 * q;
> end
>
> The error:
>
> Error in ==> ShiftBinary at 7
> q = floor (e2/3);
>
> ??? Output argument "E" (and maybe others) not assigned during call to
> "C:\Users\ABDO\Documents\MATLAB\ShiftBinary.m>ShiftBinary".
>
> Error in ==> Convert2to8Exp at 8
> [E,F,e]= ShiftBinary(F2,e2);%Calling the function
>
> Error in ==> convertSingletoOctal at 14
> [E8,F8,e8]=Convert2to8Exp(F2,e2);%Calling the function Convert2to8Exp
>
> Thank you for your help

How would you feel if someone asked you to find mistakes in a long,
sparsely
commented, code without telling you what the program is supposed to do
and
how you are trying to accomplish the task?

Greg