Undefined function or variable 'a'?

Hello, i am trying to export a plot into a jpeg file but i always get the following error message: Undefined function or variable 'a'.

The code is the following:

t=0:0.01:(3*pi)/2;
x =sin(1.8*pi*t);
plot(t,x,'r-.');
imwrite(a,'a1.jpg');

i also got the same error while trying to use saveas command instead. Does anyone know what am i doing wrong?

Answer 1

[madhan ravi]

t=0:0.01:(3*pi)/2;
x =sin(1.8.*pi.*t);
plot(t,x,'r-.');
saveas(gcf,'example.jpg')  % not imwrite

[Spiros Arkoudelis]

Thank you very much!