for loop execution error

iter1 = 1:9;

y_div_1 = 4; y_div_2 = 5; y_div_3 = 3; y_div_4 = 6; y_div_5 = 3; y_div_6 = 4; y_div_7 = 5; y_div_8 = 5; y_div_9 = 4;

x_div_1 = 4; x_div_2 = 5; x_div_3 = 3; x_div_4 = 6; x_div_5 = 3; x_div_6 = 4; x_div_7 = 5; x_div_8 = 5; x_div_9 = 4;

inodes = 1

for iter1 = 1:9

for i_y = 1:eval(['y_div_' num2str(iter1) '+ 1'])

for i_x = 1:eval(['x_div_' num2str(iter1) '+ 1'])

eval(['NODES' num2str(iter1) '(inodes,1) = 10000 + x_div_' num2str(iter1) '* (i_y - 1) + i_x'])

inodes = inodes + 1;

end

end

end

what is the issue with this code why it is not working?

Answer 1

[Image Analyst]

While the original code

iter1 = 1:9;
y_div_1 = 4; y_div_2 = 5; y_div_3 = 3; y_div_4 = 6; y_div_5 = 3; y_div_6 = 4; y_div_7 = 5; y_div_8 = 5; y_div_9 = 4;
x_div_1 = 4; x_div_2 = 5; x_div_3 = 3; x_div_4 = 6; x_div_5 = 3; x_div_6 = 4; x_div_7 = 5; x_div_8 = 5; x_div_9 = 4;
inodes = 1
for iter1 = 1:9
	for i_y = 1:eval(['y_div_' num2str(iter1) '+ 1'])
		for i_x = 1:eval(['x_div_' num2str(iter1) '+ 1'])
			eval(['NODES' num2str(iter1) '(inodes,1) = 10000 + x_div_' num2str(iter1) '* (i_y - 1) + i_x'])
			inodes = inodes + 1;
		end
	end
end

runs, it is bad for at least 2 reasons. The first line is not needed at all, and you use eval(). Also, you don't need to have a bunch of separate variables when you can just use an array. Also not sure why you're adding 1 which causes it to go beyond the end of the array. Corrected code (I think, though I don't know what you want to do) is:

y_div = [4; 5; 3; 6; 3; 4; 5; 5; 4];
x_div = [4; 5; 3; 6; 3; 4; 5; 5; 4];
nodeCount = 1;

for iter1 = 1: length(x_div)
	fprintf('Iteration %d.\n', iter1);
	for i_y = 1:y_div(iter1)
		for i_x = 1:x_div(iter1)
			NODES{iter1, nodeCount} = 10000 + x_div(iter1) * (i_y - 1) + i_x;
			nodeCount = nodeCount + 1;
		end
	end
end
fprintf('nodeCount = %d.\n', nodeCount);