parfor issue: reference to a cleared variable

Question

Jeremy 2014-7-9

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/141152-parfor-issue-reference-to-a-cleared-variable

评论： Jeremy 2014-7-9

I have some code that was written with R2011b that has been working fine for a while. It made calls to matlabpool, and R2014 gave me a warning every time I ran it that I should be using parpool. I sometime have to run the code on a computer with R2011b though, so I modified the code to run verLessThan and then use either matlabpool or parpool depending on the version. Below is the code in its entirety

function DPSimDriver( )
ticID = tic;
seed_value = randi(200000);
rand('seed', seed_value);
NineWeights = [.085 .064 .128 .085 .128 .064 .085 .170 .191];
EightWeights = [.091 0 .137 .091 .137 .068 .091 .182 .204];
SevenWeights = [.097 0 .147 .097 .147 0 .097 .195 .219];
SixWeights = [.108 0 .163 0 .163 0 .108 .216 .243];
FiveWeights = [.121 0 .182 0 .182 0 0 .242 .272];
FourWeights = [0 0 .207 0 .207 0 0 .276 .310];
ThreeWeights = [0 0 0 0 .262 0 0 .348 .391];
m = csvread('design.txt');
p = ProgressBar(size(m,1));
cores = getenv('NUMBER_OF_PROCESSORS');
if verLessThan('matlab', '8.3.0.532')
    %old version, use matlabpool
    if matlabpool('size') == 0
        matlabpool('open', cores)
    end
else
    %newer version, use parpool
    poolObj = gcp('nocreate'); %if no pool, do not create new one
    if isempty(poolObj)
        parpool('local')
    end 
end
parfor i = 1:size(m,1)
    RunNumber = m(i,1);
    ModelSize = m(i,2);
    AlphaLevel = m(i,3);
    Sensitivity = m(i,4);
    Arrival = m(i,5);
    Departure = m(i,6);
      switch ModelSize
          case 3
              Weights = ThreeWeights;
          case 4
              Weights = FourWeights;
          case 5
              Weights = FiveWeights;
          case 6
              Weights = SixWeights;
          case 7
              Weights = SevenWeights;
          case 8
              Weights = EightWeights;
          case 9
              Weights = NineWeights;
      end
      DPSim(RunNumber, Weights, AlphaLevel, Sensitivity, Arrival, Departure);
      p.progress;
  end
p.stop;
fileID2 = -1;
while fileID2 == -1
    fileID2 = fopen('projects_results.txt', 'a');
end
fprintf(fileID2, 'Total run time: %s', datestr(toc(ticID)/24/3600, 'DD-HH:MM:SS'));
fclose(fileID2);
if verLessThan('matlab', '8.3.0.532')
    matlabpool('close');
else
    poolObj = parpool;
    delete(poolObj);
end
end

The only thing that has changed between the above code and the previously running version is the addition of the if verLessThan block to change between matlabpool and parpool.

Now when I run this, I get the error message

Error using DPSimDriver>(parfor body) (line 61) Reference to a cleared variable Weights.

Line 61 is the call to

DPSim(RunNumber, Weights, AlphaLevel, Sensitivity, Arrival, Departure);

The variable Weights is only used within the body of the parfor loop, so I don't understand what the issue is. Can someone enlighten me?

Thanks in advance!

2 个评论
显示无隐藏无

José-Luis 2014-7-9

编辑：José-Luis 2014-7-9

在 MATLAB Online 中打开

Sanity check. Since you are running on different computers, are you sure that "design.txt" contains what you think it does. If it contains a value other than 3:9 for ModelSize, then Weights will not be defined and that could explain your error.

You could put

Weights = something;

before the switch statement to see if that might be the case.

Jeremy 2014-7-9

Forehead smack!

Somehow I had saved my JMP experimental design using coded values (-1 for low, 0 for center, 1 for high) rather than actual values.

Thanks!

请先登录，再进行评论。

请先登录，再回答此问题。

parfor issue: reference to a cleared variable

2 个评论
显示无隐藏无

回答（0 个）

另请参阅

类别

标签

Community Treasure Hunt

parfor issue: reference to a cleared variable

2 个评论 显示 无隐藏 无

回答（0 个）

另请参阅

类别

标签

Community Treasure Hunt

2 个评论
显示无隐藏无