小编Bin*_*Hsu的帖子

我想将一个表从INNODB改为MEMORY ENGINE.

所以我输入了这个命令:

alter table sns ENGINE=MEMORY;

然后MySQL显示

ERROR 1114 (HY000): The table '#sql-738_19' is full

表的数据大小为1GB,我有8GB内存.

我检查了my.cnf,我没有找到更改max_size设置的位置.我不应该能够存储更多数据吗？

我正在使用scikit-learning做一些降维任务.我的训练/测试数据采用libsvm格式.它是50万列中的大型稀疏矩阵.

我使用load_svmlight_file函数加载数据,并且通过使用SparsePCA,scikit-learning抛出了输入数据错误的异常.

怎么解决？

我构建了gcc 4.8.1和libstdc ++.so.6.0.18,软链接libstdc ++.so.6.0.18到libstdc ++.so.6我检查了g ++ -v,它是4.8.1

test.cpp:11:9: error: ‘thread’ is not a member of ‘std’
     std::thread t(hello);

但即使是单行也不能编译..

怎么解决？

总代码:

#include <iostream>
#include <thread>

void hello()
{
        std::cout<<"Hello Concurrent World\n";
}

int main(int argc, char * argv[])
{
        std::thread t(hello);
        t.join();

        return 0;
}

g ++ -H -std = c ++ 11 test.cpp -o测试信息:

/usr/include/asm/errno.h
/usr/include/bits/byteswap.h
/usr/include/bits/endian.h
/usr/include/bits/errno.h
/usr/include/bits/locale.h
/usr/include/bits/sched.h
/usr/include/bits/select.h
/usr/include/bits/sigset.h
/usr/include/bits/stdio_lim.h
/usr/include/bits/sys_errlist.h
/usr/include/bits/typesizes.h
/usr/include/bits/waitflags.h
/usr/include/bits/waitstatus.h
/usr/include/errno.h
/usr/include/gnu/stubs-64.h
/usr/include/gnu/stubs.h
/usr/local/include/c++/4.8.1/bits/ctype_base.h
/usr/local/include/c++/4.8.1/bits/ctype_inline.h
/usr/local/include/c++/4.8.1/cerrno
/usr/local/include/c++/4.8.1/clocale
/usr/local/include/c++/4.8.1/cstdio
/usr/local/include/c++/4.8.1/cstdlib
/usr/local/include/c++/4.8.1/ctime
/usr/local/include/c++/4.8.1/cwctype

我正在使用XCode4和OpenCV 2.3.我编译了一份OpenCV.这是.a的信息:

libopencv_core.a: Mach-O universal binary with 3 architectures
libopencv_core.a (for architecture armv7):  current ar archive random library
libopencv_core.a (for architecture armv6):  current ar archive random library
libopencv_core.a (for architecture i386):   current ar archive random library

我将它拖到Frameworks floder中,并设置库搜索的正确路径.但是当我编译时,它发生了这样的错误:

似乎在OpenCV lib中使用的STL没有链接在.a文件中.怎么解决？

谢谢,低头.

架构armv7的未定义符号:

"___cxa_begin_catch", referenced from:
      icvReadSeq(CvFileStorage*, CvFileNode*)       in libopencv_core.a(persistence.o)
  "typeinfo for std::exception", referenced from:
      typeinfo for cv::Exceptionin libopencv_core.a(alloc.o)
  "operator delete(void*)", referenced from:
      cv::Exception::~Exception()in libopencv_core.a(alloc.o)
  "_gzputs", referenced from:
      icvPuts(CvFileStorage*, char const*)in libopencv_core.a(persistence.o)
  "std::basic_string<char, std::char_traits<char>, std::allocator<char> >::_Rep::_M_destroy(std::allocator<char> const&)", referenced from:
      cv::OutOfMemoryError(unsigned long)in …

我正在Visual C++ 2010中编写一个小程序.

这是基类的代码:

class BaseInfo {

private:
    std::map <std::string, std::string> info;
    std::vector<std::string> extra_info_key;
public:
    uint get_id ();
    //Other function is hidden
};

uint BaseInfo::get_id () {
    return (uint)atoi ((info["ID"]).c_str());
}

然后我创建一个派生类,宣布为:

class test:BaseInfo {
public:
    void f();
};

void test::f (test& inf) {
    cout<<inf.get_id()<<endl;
}

但是我收到了一个错误:

函数"BaseInfo :: get_id无法访问.

我很困惑,似乎一切都在c ++规则中.