# How to display hidden element in matrix when we add the coordinate?

2 views (last 30 days)
Sahil Bajaj on 29 Nov 2015
Commented: Sahil Bajaj on 30 Nov 2015
I have
x =
1 0 0
0 1 0
0 0 1
y=
. . .
. . .
. . .
I used y to hide elements from x as in y=x but they look like dots as I wanted to hide the elements
I want to reveal hidden elements by entering coordinates
Example
If I enter (2,2)
I want y to be displayed as
y =
. . .
. 1 .
. . .
Also,
If I were to reveal neighboring elements if x = 1, how would I do that
Walter Roberson on 30 Nov 2015
Are you trying to program the game "minesweeper" ?
Sahil Bajaj on 30 Nov 2015
kinda

Guillaume on 29 Nov 2015
Edited: Guillaume on 29 Nov 2015
It would help if you used valid matlab syntax in your question, so we don't have to guess whether your input is a cell array, a character array or something else. It would also help if you'd said what coordinate system you use ([row, column], [x, y]?).
Possibly, this is what you want:
%input variables:
x = [1 0 0; 0 1 0; 0 0 1];
y = repmat('.', [3 3]); %assume y is a char array. Maybe it's a cell array?
coords = [2 2]; %assume that first value is row, 2nd value is column?
%replace dot at coord by 1
y(coords(1), coords(2)) = '1';
%reveal neighbours where x == 1
%step 1 find bounding box. Be careful of edge, hence min/max below:
top = max(1, coords(1)-1);
bottom = min(size(y, 1), coords(1)+1);
left = max(1, coords(2)-1);
right = min(size(y, 2), coords(2)+1);
%step 2 extract bounding box from x and y
suby = y(top:bottom, left:right);
subx = x(top:bottom, left:right);
%step 3 replace neighbour that are 1 in x by '1' in y
suby(logical(subx)) = '1';
%step 4 put bounding box back in y
y(top:bottom, left:right) = suby;
However, it sounds to me that you're lacking basic knowledge of indexing in matlab, so before you try to write an interactive game, I would advise to first learn the basics of matlab.