随机分区树并行化MCMC算法的MATLAB实现

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针对大数据集的常规MCMC算法在计算上往往非常昂贵,因而提出了令人尴尬的并行MCMC(EP-MCMC),其核心思想是将数据集划分为多个子集,利用独立的采样算法处理这些子集,并最终汇总子集后验图以获取最终结果。 本文档中描述的EP-MCMC算法特别应用了随机分区树,这是一种可以处理无分布子集,便于重采样且适应多种尺度的高效算法。代码库中维护的PART实现是用MATLAB编写的,方便研究者和开发者快速上手并利用这一算法。 在使用随机分区树并行化MCMC算法的过程中,首先需要将数据划分为若干个子集,每个子集包含一定数量的数据点。例如,如果有一个包含1000个数据点的大型数据集,可以将其划分为10个子集,每个子集包含100个数据点。需要注意的是,分区的过程并不要求每个子集的大小完全相等,可以根据具体需求灵活调整。 快速开始指南给出了使用PART运行并行MCMC的基本步骤。首先,进行数据划分;其次,利用MCMC算法对每个子集进行独立的采样;最后,采用特定的组合规则将所有子集后验图汇总起来,以得到对总体数据集的近似后验分布。 本文档所讨论的算法实现是通过一个名为random-tree-parallel-MCMC-master的MATLAB代码库进行提供的,这为研究人员提供了一个实用的起点,以便在他们的数据分析工作中应用并行化MCMC技术。"

检查错误原因 creating directory /data/primary/gpseg0 ... ok creating subdirectories ... ok selecting default max_connections ... 750 selecting default shared_buffers ... 125MB selecting default timezone ... Asia/Shanghai selecting dynamic shared memory implementation ... posix creating configuration files ... ok creating template1 database in /data/primary/gpseg0/base/1 ... child process was terminated by signal 9: Killed initdb: removing data directory "/data/primary/gpseg0" 2023-06-08 08:53:53.568563 GMT,,,p22007,th-604637056,,,,0,,,seg-10000,,,,,"LOG","00000","skipping missing configuration file ""/data/primary/gpseg0/postgresql.auto.conf""",,,,,,,,"ParseConfigFile","guc-file.l",563, 20230608:16:54:12:021728 gpcreateseg.sh:VM-0-5-centos:gpadmin-[INFO]:-Start Function BACKOUT_COMMAND 20230608:16:54:12:021728 gpcreateseg.sh:VM-0-5-centos:gpadmin-[INFO]:-End Function BACKOUT_COMMAND 20230608:16:54:12:021728 gpcreateseg.sh:VM-0-5-centos:gpadmin-[INFO]:-Start Function BACKOUT_COMMAND 20230608:16:54:12:021728 gpcreateseg.sh:VM-0-5-centos:gpadmin-[INFO]:-End Function BACKOUT_COMMAND 20230608:16:54:12:021728 gpcreateseg.sh:VM-0-5-centos:gpadmin-[FATAL][0]:-Failed to start segment instance database VM-0-5-centos /data/primary/gpseg0 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-End Function PARALLEL_WAIT 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-End Function PARALLEL_COUNT 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-Start Function PARALLEL_SUMMARY_STATUS_REPORT 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:------------------------------------------------ 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-Parallel process exit status 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:------------------------------------------------ 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-Total processes marked as completed = 0 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-Total processes marked as killed = 0 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[WARN]:-Total processes marked as failed = 1 <<<<< 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:------------------------------------------------ 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-End Function PARALLEL_SUMMARY_STATUS_REPORT FAILED:VM-0-5-centos~6000~/data/primary/gpseg0~2~0

2023-06-09 上传