Basics of MATLAB and Beyond

text(-.7,f(-.7),’f(X)’)But we have made a mistake: the “x” should be lower case. We try tocorrect it by issuing another text command with a lower case “x”:text(-.7,f(-.7),’f(x)’)But this has printed over the top of the previous label, making a mess.Without starting again, we can use the delete function to delete thetext objects, once we know their handles. We can get a list of the handlesof the line and the text objects by getting all the children of the currentaxes:>> h = get(gca,’children’)h =19.000118.000111.0005The variable h is a three-element column vector (the actual values arenot important). These are the handles corresponding to the Line object(parabola) and the two Text objects. But which of them is the Lineobject and which are the Text objects? We can get the object typescorresponding to these handles by typing:>> types = get(h,’type’)types =’text’’text’’line’(The variable types is returned as a cell array.) A parent’s childrenare always listed in reverse age order: the most recently drawn objectappears first—youngest first, oldest last. This tells us that the first twoelements of the vector h correspond to the text objects ‘f(X)’ and ‘f(x)’,in that order, and the third element corresponds to the parabolic line.We can delete the two text objects by typing:c○ 2000 by CRC Press LLC