형들 내가 matlab으로 근을 찾는 코딩을 했고 gui를 이용해서 함수를 입력하고 최소 최대 구간을 정하고 오차율을 정하고 버튼만 누르면 근을 찾아주면서 그래프까지 그려주는 그런코딩을 했거든? 그게 일단 이거야
function Start_Callback(hObject, eventdata, handles)

a=str2double(get(handles.input,'String'));
b=str2double(get(handles.max,'String'));
c=str2double(get(handles.mini,'String'));
d=str2double(get(handles.error,'String'));

rt=[];
x = linspace(c, b, 10000);

for i = 1:length(x);
    y=@(x)a;
    y(x(i));
    
    
    if abs(y) < d
        rt = [rt x(i)]; 
    end
end

yrt=@(x)a;
yrt(x(i));
     

for i = 1:length(rt)

    plot(rt(i), yrt(i),'ro');
    hold on
   
end

 yi = @(x)a;
 
plot(x,yi)
hold on; grid on


a가 사용자가 함수값을 넣는곳이야 예시로 x^2+3x+2 이렇게 넣는거지, 그러면  x^2+3x+2그래프를 그려주고 x의값을 찾는건데...
이게 이 코딩 그대로 하면 abs가 function_handle'형 입력 인수에 대해 정의되지 않았습니다. 라면서 안되는데.. 이게 무슨뜻이고 이걸 고치려면 어떻게해야해?? 그리고 x^2+3x+2  에서 x를 x(i)로 바꾸게 하면서 계산하는건데 저렇게 쓰는거 맞지?? 내가 초보라 모르는게 넘많아 ㅜㅜ 형들 도와줘!