figureのコールバックを設定することにより、カーソル位置が取得可能です。
また、必要であれば datatip を利用することで、関数上のデータを取得することもできます。
By setting up a callback for the figure, it becomes possible to obtain the cursor's position.
Additionally, if needed, you can also retrieve data from the function using a "datatip".
function test
Ia_start = 1;
Ia_incre = 1;
Ia_end = 3;
figure
ax = gca;
set(gcf, 'visible', 'on','Position',[400 50 1000 940])
hold on
for Ia = Ia_start : Ia_incre : Ia_end
fp(Ia) = fimplicit(@(id,iq) id.^2+iq.^2 - Ia.^2);
% append new data tip if necessary
row = dataTipTextRow("X + Y", @(x,y)(x+y));
fp(Ia).DataTipTemplate.DataTipRows(end+1) = row;
end
hold off
f = gcf;
ax.Units = "normalized";
axWidth = f.Position(3) * ax.Position(3);
axHeight = f.Position(4) * ax.Position(4);
axSX = f.Position(3) * ax.Position(1);
axSY = f.Position(4) * ax.Position(2);
axXmin = ax.XLim(1);
axXmax = ax.XLim(2);
axYmin = ax.YLim(1);
axYmax = ax.YLim(2);
f.WindowButtonDownFcn = @getaxPos;
% mouse callback
function pos = getaxPos(src,~)
last_seltype = src.SelectionType;
C = get (gcf, 'CurrentPoint');
x = (C(1) - axSX) / axWidth * (axXmax - axXmin) + axXmin;
y = (C(2) - axSY) / axHeight * (axYmax - axYmin) + axYmin;
pos = [x, y];
if strcmp(last_seltype,'normal') % left click
% find data on the fimplicit function using "datatip"
for Ia = Ia_start : Ia_incre : Ia_end
dt(Ia) = datatip(fp(Ia),x,y);
dist(Ia) = norm([x,y] - [dt(Ia).X, dt(Ia).Y]);
end
[~,idx] = min(dist); % find nearest data from 3 fimplicits
for Ia = Ia_start : Ia_incre : Ia_end
if Ia==idx
dt(Ia).Visible = 'on';
z = dt(Ia).X + dt(Ia).Y % disp z to command window
else
dt(Ia).Visible = 'off'; % turn off other datatips
end
end
end
end
% set (f, 'WindowButtonDownFcn', '');
end
