help with MATLAB battleship program

Hi all, Im working on a battleship assignment for a class. Here is the code I have so far:

clear all
close all
clc


rowdim=input('give me the number of rows on the board: ');
coldim=input('give me the number of columns on the board: ');
GameBoard=zeros(rowdim,coldim); %defined board dimensions

%matlab puts a random ship on the board
battleship_row=randi(rowdim,[1 1]) %random row
battleship_col=randi(coldim,[1 1]) %random column
GameBoard(battleship_row,battleship_col)=0;%%'0' hides the loaction of the battleship (unless it is correct)

%playguess
for guessnum=1:5
    rowguess=input('guess what row the battleship is in: ');
    colguess=input('guess what column the battleship is in: ');
    [winloss]=results(rowguess,colguess,battleship_row,battleship_col);
    %assesses the results
    if winloss == 1
        GameBoard(rowguess,colguess)=3; %marks winning guess with '3' on board
        break; %finishes the loop, because you won
        GameBoard %displays the winning gameboard
    else
        disp('try again')
        GameBoard(rowguess,colguess)=2; %mark loss with '2' on board if guess is incorrect
        GameBoard %displays the gameboard to visualize your loss
    end
end

GameBoard
    

[winloss]=results(rowguess,colguess,battleship_row,battleship_col); %calling subplot

%subfunction from here on

function [winloss]=results(rowguess,colguess,battleship_row,battleship_col)

if (rowguess == battleship_row) && (colguess == battleship_col);
    winloss=1;
    disp ('You sunk the battleship! You won!');
else
    winloss=0;
    disp(' ');
end


end

I would like to add more battleships to the game board (there is currently only 1) . What are some ways I can go about doing that?

Answer 1

[Walter Roberson]

N = 5;
battleship_row=randi(rowdim,[1 N]) %random row
battleship_col=randi(coldim,[1 N]) %random column

%the following is actually useless as you initialized GameBoard to all 0
%anyhow
GameBoard(sub2ind(size(GameBoard,battleship_row,battleship_col))=0;

but you need to change

if (rowguess == battleship_row) && (colguess == battleship_col);

to

if any((rowguess == battleship_row) & (colguess == battleship_col))

[Alex Skantz]

Thank you!!!!!!

[Image Analyst]

I'm not sure what that does "to add more battleships to the game board". Alex or Walter's present code seems like it would just place one ship on the board.

And that if statement just says that there is a win if a single location in the battleship was hit. The way I always played the game was that you had to hit all the spots in a ship to sink it, like all 5 for a battleship or all 4 for a cruiser or whatever.

[Walter Roberson]

@Image Analyst

No, my change causes N single-space ships to be added to the board. But unless the user changes more of their code, hitting any one of them would be a "win".

Answer 2

[Image Analyst]

You need a function that's called BuildBoard() or something. Then in there call a function called PlaceShip() the required number of times.

function gameBoard = BuildBoard(rows, columns, numberOfShips)
gameBoard = false(rows, columns); % Initialize a blank board.
maxShipLength = 5;
shipSizes = randi(maxShipLength, 1, numberOfShips)
for k = 1 : numberOfShips
    gameBoard = PlaceShip(shipSizes(k));
end

Then in PlaceShip() you get a random location and direction. Then see if any of those locations is yet occupied by a prior ship. If none are then set those locations of gameBoard to true, otherwise try a different location until you succeed in placing it.