How can I remove those contour lines outside the map?

Hello everyone.

Using the code below, I can plot contour lines outlining frost depth values across the Minnesota. As can be seen in the output figures, some contour lines are shown outside the Minnesota map. Would you please help me solve this issue? Indeed, I just want to have contour lines within the Minnesota state.

clear
close all
clc
load("saved_data.mat")
[lon,lat] = meshgrid(-97.24:0.1:-89.48,43.49:0.1:49.38);
for v = 1:(size(data, 2)-2)
    figure
    usamap("Minnesota")
    states=readgeotable("usastatehi.shp");
    row=states.Name=="Minnesota";
    Minnesota=states(row,:);
    geoshow(Minnesota)
    textm(Minnesota.LabelLat,Minnesota.LabelLon,Minnesota.Name,"HorizontalAlignment","center")
    I = scatteredInterpolant(data(:,[2 1]), data(:,v+2));
    I.Method='linear';
    I.ExtrapolationMethod='linear';
    contourm(lat,lon,min(1,max(0,I(lon,lat))));
    colorbar('Ticks',[0.1, 0.3, 0.5, 0.7, 0.9, 1], 'TickLabels',{'0.1','0.3','0.5','0.7','0.9','1'})
    
end

Answer 1

[Image Analyst]

If you have (x,y) coordinates of the outline of the state, and a list of (x,y) coordinates you want to check, you can use inpolygon.

[Behrooz Daneshian]

Thank you very much.