MATLAB Fundamentals＞＞＞Smoothing Data with Moving Average

MATLAB Fundamentals>Common Data Analysis Techniques>Smoothing Data> (2/5)?Smoothing Data with Moving Average

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例1：

Smoothing method:Moving mean

Moving window:Centered 2

代码2：

% Smooth input data
ySm = smoothdata(y,"movmean",2,"SamplePoints",x);

% Display results
figure
plot(x,y,"SeriesIndex",6,"DisplayName","Input data")
hold on
plot(x,ySm,"SeriesIndex",1,"LineWidth",1.5, ...
    "DisplayName","Smoothed data")
hold off
legend
xlabel("x")

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例2：

Smoothing method:Moving mean

Smoothing factor:0.25

代码2：

% Smooth input data
ySm = smoothdata(y,"movmean","SmoothingFactor",0.25,"SamplePoints",x);

% Display results
figure
plot(x,y,"SeriesIndex",6,"DisplayName","Input data")
hold on
plot(x,ySm,"SeriesIndex",1,"LineWidth",1.5, ...
    "DisplayName","Smoothed data")
hold off
legend
xlabel("x")

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例3：

Smoothing method:Moving median

Moving window:Centered 2

代码3：

% Smooth input data
ySm = smoothdata(y,"movmedian",2,"SamplePoints",x);

% Display results
figure
plot(x,y,"SeriesIndex",6,"DisplayName","Input data")
hold on
plot(x,ySm,"SeriesIndex",1,"LineWidth",1.5, ...
    "DisplayName","Smoothed data")
hold off
legend
xlabel("x")

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例4：

Smoothing method:Gaussian filter

Moving window:Centered 2

代码4：

% Smooth input data
ySm = smoothdata(y,"gaussian",2,"SamplePoints",x);

% Display results
figure
plot(x,y,"SeriesIndex",6,"DisplayName","Input data")
hold on
plot(x,ySm,"SeriesIndex",1,"LineWidth",1.5, ...
    "DisplayName","Smoothed data")
hold off
legend
xlabel("x")

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例5：

Smoothing method:Local linear regression(lowess)

Moving window:Centered 2

代码5：

% Smooth input data
ySm = smoothdata(y,"lowess",2,"SamplePoints",x);

% Display results
figure
plot(x,y,"SeriesIndex",6,"DisplayName","Input data")
hold on
plot(x,ySm,"SeriesIndex",1,"LineWidth",1.5, ...
    "DisplayName","Smoothed data")
hold off
legend
xlabel("x")

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例6：

Smoothing method:Local quadratic?regression(loess)

Moving window:Centered 2

代码6：

% Smooth input data
ySm = smoothdata(y,"loess",2,"SamplePoints",x);

% Display results
figure
plot(x,y,"SeriesIndex",6,"DisplayName","Input data")
hold on
plot(x,ySm,"SeriesIndex",1,"LineWidth",1.5, ...
    "DisplayName","Smoothed data")
hold off
legend
xlabel("x")

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例7：

Smoothing method:Robust Lowess

Moving window:Centered 2

代码7：

% Smooth input data
ySm = smoothdata(y,"rlowess",2,"SamplePoints",x);

% Display results
figure
plot(x,y,"SeriesIndex",6,"DisplayName","Input data")
hold on
plot(x,ySm,"SeriesIndex",1,"LineWidth",1.5, ...
    "DisplayName","Smoothed data")
hold off
legend
xlabel("x")

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例8：

Smoothing method:Roubst Loess

Moving window:Centered 2

代码8：

% Smooth input data
ySm = smoothdata(y,"rloess",2,"SamplePoints",x);

% Display results
figure
plot(x,y,"SeriesIndex",6,"DisplayName","Input data")
hold on
plot(x,ySm,"SeriesIndex",1,"LineWidth",1.5, ...
    "DisplayName","Smoothed data")
hold off
legend
xlabel("x")

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例9：

Smoothing method:Savitzky-Golay polynomial filter

polynomial degree:2

Moving window:Centered 2

代码9：

% Smooth input data
ySm = smoothdata(y,"sgolay",2,"SamplePoints",x);

% Display results
figure
plot(x,y,"SeriesIndex",6,"DisplayName","Input data")
hold on
plot(x,ySm,"SeriesIndex",1,"LineWidth",1.5, ...
    "DisplayName","Smoothed data")
hold off
legend
xlabel("x")