% Main script to read boiling point data and provide user options
clear; clc;

% Import data from file
data = importdata('data.txt');

% Extract pressure and temperature values
pressure = data(:, 1); % First column: Pressure (bar)
temperature = data(:, 2); % Second column: Boiling Temperature (°C)

while true
    % Display menu options
    disp('Type:');
    disp('1 to find the boiling point for a specific pressure');
    disp('2 to print the known experimental values');
    disp('3 to create a table of values in a desired pressure interval');
    disp('0 to exit');
    
    choice = input('Enter your choice: ');
    
    if choice == 1 % Find boiling point for specific pressure
        user_pressure = input('Enter pressure in bar: ');
        idx = find(pressure == user_pressure);
        
        if ~isempty(idx) % Exact match found
            fprintf('The boiling point at %.1f bar is %.1f °C (experimental value).\n', ...
                    user_pressure, temperature(idx));
        else % Perform linear interpolation
            if user_pressure < min(pressure) || user_pressure > max(pressure)
                fprintf('Pressure out of range. Please enter a value between %.1f and %.1f bar.\n', ...
                        min(pressure), max(pressure));
            else
                interp_temp = linear_interpolation(pressure, temperature, user_pressure);
                fprintf('The estimated boiling point at %.1f bar is %.1f °C (linear interpolation).\n', ...
                        user_pressure, interp_temp);
            end
        end
        
    elseif choice == 2 % Print known experimental values
        fprintf('\nPressure (bar) | Boiling Temperature (°C)\n');
        fprintf('----------------|--------------------------\n');
        for i = 1:length(pressure)
            fprintf('%16.1f | %24.1f\n', pressure(i), temperature(i));
        end
        
    elseif choice == 3 % Create table of values in a desired pressure interval
        min_pressure = input('Enter minimum pressure (bar): ');
        max_pressure = input('Enter maximum pressure (bar): ');
        step_size = input('Enter step size (bar): ');
        
        if min_pressure < min(pressure) || max_pressure > max(pressure) || step_size <= 0
            fprintf('Invalid input range or step size.\n');
        else
            new_pressures = min_pressure:step_size:max_pressure;
            new_temperatures = arrayfun(@(p) linear_interpolation(pressure, temperature, p), new_pressures);
            
            fprintf('\nPressure (bar) | Estimated Temperature (°C)\n');
            fprintf('----------------|----------------------------\n');
            for i = 1:length(new_pressures)
                fprintf('%16.1f | %26.1f\n', new_pressures(i), new_temperatures(i));
            end
        end
        
    elseif choice == 0 % Exit the program
        disp('Exiting...');
        break;
        
    else
        disp('Invalid choice, please try again.');
    end
    
    disp(' '); % Add space for readability between iterations
end