编译mathgl示例c ++

Question

我已经安装了mathgl，使用：

{.class}

当我尝试编译示例c ++程序from here

时

# Heading 1 {.my_class_for_heading1}

Here is some `code`{.my_class_for_code} and 
for a [span]{.my_class_for_span} it is working as well
and for img and url it is available as well
for [pandoc](http://www.pandoc.org/){.my_class_for_url}

使用sudo apt-get install mathgl sudo apt-get install libmgl-dev 我在mathgl函数中遇到编译器错误。

#include <mgl2/qt.h>
int sample(mglGraph *gr)
{
  gr->Rotate(60,40);
  gr->Box();
  return 0;
}
//-----------------------------------------------------
int main(int argc,char **argv)
{
  mglQT gr(sample,"MathGL examples");
  return gr.Run();
}

我尝试运行python示例，它工作正常。 有谁知道如何解决这个问题？