我一直在运行从here下载的DoseResponse函数的变体，以生成剂量-ReactSigmoid曲线。然而，我的一个数据集在生成线性曲线时遇到了问题。通过运行以下代码，我得到以下错误并生成以下图形。我还将名为dose2.csv和res2.csv的数据上传到了Google Drive here。有人知道我怎么解决这个问题吗？谢谢。
用于生成图形的代码

% Plotting Dose-Response Curve
response = resp2;
dose = dose2; 

% Deal with 0 dosage by using it to normalise the results.
normalised=0;
if (sum(dose(:)==0)>0)
    %compute mean control response
    controlResponse=mean(response(dose==0));
    %remove controls from dose/response curve
    response=response(dose~=0)/controlResponse;
    dose=dose(dose~=0);
    normalised=1;
end

%hill equation sigmoid
sigmoid=@(beta,x)beta(1)+(beta(2)-beta(1))./(1+(x/beta(3)).^beta(4));

%calculate some rough guesses for initial parameters
minResponse=min(response);
maxResponse=max(response);
midResponse=mean([minResponse maxResponse]);
minDose=min(dose);
maxDose=max(dose);

%fit the curve and compute the values
%[coeffs,r,J]=nlinfit(dose,response,sigmoid,[minResponse maxResponse midResponse 1]); % nlinfit doesn't work as well
beta_new = lsqcurvefit(sigmoid,[minResponse maxResponse midResponse 1],dose,response);
[coeffs,r,J]=nlinfit(dose,response,sigmoid, beta_new);

ec50=coeffs(3);
hillCoeff=coeffs(4);

%plot the fitted sigmoid
xpoints=logspace(log10(minDose),log10(maxDose),1000);
semilogx(xpoints,sigmoid(coeffs,xpoints),'Color',[1 0 0],'LineWidth',2)
hold on

%notate the EC50
text(ec50,mean([coeffs(1) coeffs(2)]),[' \leftarrow ' sprintf('EC_{50}=%0.2g',ec50)],'FontSize',20,'Color',[1 0 0]);

%plot mean response for each dose with standard error
doses=unique(dose);
meanResponse=zeros(1,length(doses));
stdErrResponse=zeros(1,length(doses));
for i=1:length(doses)
    responses=response(dose==doses(i));
    meanResponse(i)=mean(responses);
    stdErrResponse(i)=std(responses)/sqrt(length(responses));
    %stdErrResponse(i)=std(responses);
end

errorbar(doses,meanResponse,stdErrResponse,'o','Color',[1 0 0],'LineWidth',2,'MarkerSize',12)

警告消息

Solver stopped prematurely.

lsqcurvefit stopped because it exceeded the function evaluation limit,
options.MaxFunctionEvaluations = 4.000000e+02.

Warning: Iteration limit exceeded.  Returning results from final iteration.

图表(希望生成不是线性的Sigmoid曲线)