I have a latitude longitude infos and a certain data. I am tryna do a 2D contour earth map using all of these. But result not right why ?

Here is my code. But the result map is not right. How can i visualize?

% Load latitude and longitude data
latTable = readtable('C:\Users\gozde\Desktop\sat_lat.xlsx');
lat = latTable.Column2; 

longTable = readtable('C:\Users\gozde\Desktop\sat_long.xlsx');
long = longTable.Column3; 

% Load your data from the CSV file
mTable = readtable('C:\Users\gozde\Desktop\genel unzip\GENEL\GENELims\BUS_DATA_COMBINED.csv', 'Range', 'L2:N17026');
m = mTable{:,:};

% Calculate the magnitude of vectors
MAG = zeros(size(m, 1), 1);
for i = 1:size(m, 1)
    MAG(i) = norm(m(i, :));
end

% Create a 2D map of the Earth
figure;
worldmap world;
load coastlines; % Load coastlines for reference
geoshow(coastlat, coastlon, 'DisplayType', 'line', 'Color', 'black');

% Convert latitude and longitude to double arrays
lat = double(lat);
long = double(long);

% Create regularly spaced x and y values
xq = linspace(min(lat), max(lat), 50);
yq = linspace(min(long), max(long), 50);
[Xq, Yq] = meshgrid(xq, yq);

% Use the scattered interpolant to compute the grid of Z values
F = scatteredInterpolant(lat, long, MAG, 'linear', 'linear');
Zq = F(Xq, Yq);

% Create the contour plot
contourm(Xq, Yq, Zq, 'LineColor', 'black'); % Adjust LineColor as needed
colorbar;

framem on;
gridm on;
mlabel on;
plabel on;
colormap('jet');

Here it is my result.

And i want a result like this

[Voss]

Can you attach the 2 xlsx files and 1 csv file you are using?

[Gözde]

Hi @Voss thanks for your attention but i can not share file or datas. Kinda forbidden lets say. But i rearrenge the code and maybe you can say how can i improve the new version of code. I filtered the code via Gaussian filter to reach smoother image. I know it is hard to estimate without the datas but thanks in advance !

% Load latitude and longitude data
latTable = readtable('C:\Users\gozde\Desktop\sat_lat.xlsx');
lat = latTable.Column2; % Latitude column name is Column2

longTable = readtable('C:\Users\gozde\Desktop\sat_long.xlsx');
long = longTable.Column3; % Longitude column name is Column3

% magnetometer data from the CSV file
mTable = readtable('C:\Users\gozde\Desktop\genel unzip\GENEL\GENELims\BUS_DATA_COMBINED.csv', 'Range', 'L2:N17026');
m = mTable{:,:};

% Calculate the magnitude of magnetometer 
MAG = zeros(size(m, 1), 1);
for i = 1:size(m, 1)
    MAG(i) = norm(m(i, :));
end

% Creating regularly spaced grid for interpolation
xq = linspace(min(lat), max(lat), 50);
yq = linspace(min(long), max(long), 50);
[Xq, Yq] = meshgrid(xq, yq);

% Interpolate magnetometer data to the regular grid
Zq = griddata(lat, long, MAG, Xq, Yq, 'cubic'); % You can adjust the smoothing method ('cubic' or 'linear')

% Smooth the data using a Gaussian filter
sigma = 1; % Adjust the smoothing factor as needed
Zq_smoothed = imgaussfilt(Zq, sigma);

% Create a contour plot
figure;
contourf(Xq, Yq, Zq_smoothed, 20, 'LineColor', 'k'); % Adjust the number of contour levels as needed
colorbar;

xlabel('Latitude');
ylabel('Longitude');
title('Magnetometer 2D Contour Map with Gaussian Smoothing');
colormap('jet');

[Gözde]

Also It doesn't have to look exactly like the first figure. Something like this works for me. (this is the image my code should look like)

Answer 1

[Voss]

% some fake data:
N = 17025;
lat = rand(N,1)*180-90;
long = rand(N,1)*360-180;
m = rand(N,4);

% Calculate the magnitude of magnetometer 
MAG = zeros(size(m, 1), 1);
for i = 1:size(m, 1)
    MAG(i) = norm(m(i, :));
end

% Create a 2D map of the Earth
figure;
worldmap world;

% Create regularly spaced x and y values
xq = linspace(min(lat), max(lat), 50);
yq = linspace(min(long), max(long), 50);
[Xq, Yq] = meshgrid(xq, yq);

% Use the scattered interpolant to compute the grid of Z values
F = scatteredInterpolant(lat, long, MAG, 'linear', 'linear');
Zq = F(Xq, Yq);

% Create the contour plot
contourfm(Xq, Yq, Zq, 'LineColor', 'none');

load coastlines; % Load coastlines for reference
geoshow(coastlat, coastlon, 'DisplayType', 'line', 'Color', 'black');

colorbar;
framem on;
gridm on;
mlabel on;
plabel on;
colormap('jet');