Octave添加第二个函数后出现‘LMSregression未定义’错误

你的问题根源是**clear all命令清除了之前定义的函数**：在脚本中，clear all写在两个函数定义之后，执行该命令会清空工作区所有变量，同时删除已加载的函数定义，导致后续调用LMSregression时找不到该函数。

以下是三种可行的解决办法：

• 方案1：调整clear all的位置，移到脚本最开头（占位符之后、函数定义之前）

  1;
  clear all;
  
  %%=========INTERPOLATION FUNCTION=================
  function Y=interpdata(x1,y1,x2,y2,X)
      Y=interp1([x1,x2],[y1,y2],X);
  endfunction
  %%=====end of INTERPOLATION FUNCTION==============
  
  %%=========LEAST MEAN SQUARE FUNCTION=============
  function coef=LMSregression(mat,size_)
      sumX2=0;
      sumXY=0;
      sumX=0;
      sumY=0;
      for i=1:size_
          sumX=sumX+mat(i,1);
          sumY=sumY+mat(i,2);
          sumX2=sumX2+mat(i,1)*mat(i,1);
          sumXY=sumXY+mat(i,1)*mat(i,2);
      endfor
      slope = (size_ * sumXY - sumX * sumY) /(size_ * sumX2 -sumX * sumX);
      b = sumY/size_ - slope * sumX/size_;
      coef = [slope b];
  endfunction
  %%=======end of LEAST MEAN SQUARE FUNCTION========
  
  %%============CALIBRATION AND DIVISION============
  data_ = dlmread ("mono00.txt", ";");
  size_data=size(data_);
  
  counter1=1;
  counter2=1;
  counter3=1;
  for i=1:size_data(1)
      if data_(i,1)==1
          zone1(counter1,:)=data_(i,:);
          counter1=counter1+1;
      elseif data_(i,1)==2
          zone2(counter2,:)=data_(i,:);
          counter2=counter2+1;
      elseif data_(i,1)==3
          zone3(counter3,:)=data_(i,:);
          counter3=counter3+1;
      endif
  endfor
  %%======end of CALIBRATION AND DIVISION===========
  
  %% 后续代码保持不变
  

• 方案2：替换clear all为clear variables，只清除工作区变量，保留函数定义

  1;
  %%=========INTERPOLATION FUNCTION=================
  function Y=interpdata(x1,y1,x2,y2,X)
      Y=interp1([x1,x2],[y1,y2],X);
  endfunction
  %%=====end of INTERPOLATION FUNCTION==============
  
  %%=========LEAST MEAN SQUARE FUNCTION=============
  function coef=LMSregression(mat,size_)
      sumX2=0;
      sumXY=0;
      sumX=0;
      sumY=0;
      for i=1:size_
          sumX=sumX+mat(i,1);
          sumY=sumY+mat(i,2);
          sumX2=sumX2+mat(i,1)*mat(i,1);
          sumXY=sumXY+mat(i,1)*mat(i,2);
      endfor
      slope = (size_ * sumXY - sumX * sumY) /(size_ * sumX2 -sumX * sumX);
      b = sumY/size_ - slope * sumX/size_;
      coef = [slope b];
  endfunction
  %%=======end of LEAST MEAN SQUARE FUNCTION========
  
  clear variables;  % 替换原有的clear all
  
  %%============CALIBRATION AND DIVISION============
  data_ = dlmread ("mono00.txt", ";");
  size_data=size(data_);
  
  counter1=1;
  counter2=1;
  counter3=1;
  for i=1:size_data(1)
      if data_(i,1)==1
          zone1(counter1,:)=data_(i,:);
          counter1=counter1+1;
      elseif data_(i,1)==2
          zone2(counter2,:)=data_(i,:);
          counter2=counter2+1;
      elseif data_(i,1)==3
          zone3(counter3,:)=data_(i,:);
          counter3=counter3+1;
      endif
  endfor
  %%======end of CALIBRATION AND DIVISION===========
  
  %% 后续代码保持不变
  

• 方案3：遵循Octave规范，将所有函数定义移至文件末尾（所有执行代码之后）

  1;
  clear all;
  
  %%============CALIBRATION AND DIVISION============
  data_ = dlmread ("mono00.txt", ";");
  size_data=size(data_);
  
  counter1=1;
  counter2=1;
  counter3=1;
  for i=1:size_data(1)
      if data_(i,1)==1
          zone1(counter1,:)=data_(i,:);
          counter1=counter1+1;
      elseif data_(i,1)==2
          zone2(counter2,:)=data_(i,:);
          counter2=counter2+1;
      elseif data_(i,1)==3
          zone3(counter3,:)=data_(i,:);
          counter3=counter3+1;
      endif
  endfor
  %%======end of CALIBRATION AND DIVISION===========
  
  %%=================DATA CLEAN AND SORT============
  zone1=[zone1(:,2) zone1(:,6) ];
  zone2=[zone2(:,2) zone2(:,6) ];
  zone3=[zone3(:,2) zone3(:,6) ];
  zone1=sortrows(zone1, 1);
  zone2=sortrows(zone2, 1);
  zone3=sortrows(zone3, 1);
  size_zone1=counter1-1;
  size_zone2=counter2-1;
  size_zone3=counter3-1;
  %%===========end of DATA CLEAN AND SORT===========
  
  %%=================LMS REGRESSION=================
  coefs=zeros(3,2);
  coefs(1,:)=LMSregression(zone1, size_zone1);
  X1=linspace(min(zone1(:,1)), max(zone1(:,1)),100);
  coefs(2,:)=LMSregression(zone2, size_zone2);
  X2=linspace(min(zone2(:,1)), max(zone2(:,1)),100);
  coefs(3,:)=LMSregression(zone3, size_zone3);
  X3=linspace(min(zone3(:,1)), max(zone3(:,1)),100);
  %%=============end of LMS REGRESSION==============
  
  %%=========INTERPOLATION FUNCTION=================
  function Y=interpdata(x1,y1,x2,y2,X)
      Y=interp1([x1,x2],[y1,y2],X);
  endfunction
  %%=====end of INTERPOLATION FUNCTION==============
  
  %%=========LEAST MEAN SQUARE FUNCTION=============
  function coef=LMSregression(mat,size_)
      sumX2=0;
      sumXY=0;
      sumX=0;
      sumY=0;
      for i=1:size_
          sumX=sumX+mat(i,1);
          sumY=sumY+mat(i,2);
          sumX2=sumX2+mat(i,1)*mat(i,1);
          sumXY=sumXY+mat(i,1)*mat(i,2);
      endfor
      slope = (size_ * sumXY - sumX * sumY) /(size_ * sumX2 -sumX * sumX);
      b = sumY/size_ - slope * sumX/size_;
      coef = [slope b];
  endfunction
  %%=======end of LEAST MEAN SQUARE FUNCTION========
  

内容的提问来源于stack exchange，提问作者ATSlooking4things