生成带有gui的基于MATLAB的fft变换代码，能够在GUI界面导入音频文件，生成波形图，并进行FFT变换生成频谱图

以下是一个简单的MATLAB GUI程序，可以导入音频文件并生成波形图和频谱图：

function fft_gui()
% Create the GUI
f = figure('Visible','off','Position',[360,500,450,285]);

% UI elements
load_button = uicontrol('Style','pushbutton','String','Load Audio',...
    'Position',[315,220,100,25], 'Callback', @load_callback);
plot_button = uicontrol('Style','pushbutton','String','Plot',...
    'Position',[315,180,100,25], 'Callback', @plot_callback);
axes_wave = axes('Units','Pixels','Position',[50,60,200,200]);
axes_fft = axes('Units','Pixels','Position',[250,60,200,200]);

% Initialize variables
audio_data = [];
audio_fs = 0;

% Show the GUI
f.Visible = 'on';

% Callback function for load button
    function load_callback(hObject,eventdata)
        % Open file dialog
        [file_name, path_name] = uigetfile({'*.wav';'*.mp3'},'Select Audio File');
        if isequal(file_name,0)
            return;
        end
        
        % Read audio file
        [audio_data, audio_fs] = audioread(fullfile(path_name,file_name));
    end

% Callback function for plot button
    function plot_callback(hObject,eventdata)
        if isempty(audio_data)
            return;
        end
        
        % Plot waveform
        axes(axes_wave);
        plot(audio_data);
        xlabel('Time (samples)');
        ylabel('Amplitude');
        
        % Perform FFT
        L = length(audio_data);
        Y = fft(audio_data);
        P2 = abs(Y/L);
        P1 = P2(1:L/2+1);
        P1(2:end-1) = 2*P1(2:end-1);
        f = audio_fs*(0:(L/2))/L;
        
        % Plot frequency spectrum
        axes(axes_fft);
        plot(f,P1);
        xlabel('Frequency (Hz)');
        ylabel('Power');
    end

end

运行此程序后，您将看到一个具有“Load Audio”和“Plot”按钮的GUI。单击“Load Audio”按钮以打开文件对话框并选择音频文件。然后单击“Plot”按钮以生成波形图和频谱图。波形图将显示在左侧的坐标轴中，而频谱图将显示在右侧的坐标轴中。