Wht is my failure?

I want to write a function, which Shows the Martingale Strategy for a Gambler. For the beginning I started to Code a single Round for the game:

function Capital = roulette1 (Startcap)
%% Capital should Show the Money at the end of the round, if the Gambler won or lost the round
%% StartCap should be the Money the Gambler is starting with, for Example: the Gambler Starts with 100$

   Capital = EndCap

   if rem(randi(37),2)==0
%% if the Gambler is winning the game he wins the Money he was Setting, in here he is betting 1$

     EndCap = Startcap +1
   else     %% or the Gambler loses 1$
      Endcap = Startcap - 1
   end
  end

Matlab Shows me always the error that the variable Endcap is undefined. What is my failure? Thanks for help and answers.

Answer 1

[Image Analyst]

When you say this:

Capital = EndCap

exactly what value do you think the undefined EndCap should have? 3? pi? 42? How is the code supposed to know? It doesn't - you need to tell it. It can't just make up some arbitrary value for EndCap.

Perhaps you want this:

Capital = Startcap;
if rem(randi(37),2) == 0
  %%if the Gambler is winning the game he wins the Money he was Setting, in here he is betting 1$
  Capital = Capital + 1;
else     %%or the Gambler loses 1$
  Capital = Capital - 1;
end

I don't see a need for EndCap at all since Capital is the running balance - the amount of money the gambler currently has.