minor grid in consecutive plots

If I run the following code (within a script or command window) several times, then the minor grids will be 'on' only every other time. Why?

x=-2*pi:0.1:2*pi;
y=sin(x);
figure(1)
hold on
plot(x,y);
grid on 
grid minor

Answer 1

[Walter Roberson]

grid minor toggles the visibility of the minor grid lines. Minor grid lines lie between the tick marks. Not all types of charts support minor grid lines.

https://www.mathworks.com/help/matlab/ref/grid.html

You probably want

set(gca, 'XMinorGrid', 'on', 'YMinorGrid', 'on')

[G A]

Thanks, Walter! With that line you have given instead of grid minor my code works now properly for each run. However, still, why with the run number 1,3,5... the code with grid minor gives proper result and with the run number 2,4,6,... it gives a wrong result?

[Walter Roberson]

grid minor toggles the visibility of the minor grid lines

https://www.mathworks.com/help/matlab/ref/grid.html

So the first time you call it, it turned it from default off to on. The second time you call it, it turns it off. The third time you call it, it turns it on...

[G A]

Understood. Thanks!