我正在尝试在我的Ubuntu Server 12.04上的virtualenv中安装OpenCV.我找到了一个讨论这个问题的线程,但设法从中提取没有信息.
我尝试使用pip install pyopencv但失败了.
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package/extras/core/ndarray.cpp:598:1: instantiated from here
package/extras/core/ndarray.cpp:546:9: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘Py_intptr_t {aka long int}’ [-Wformat]
package/extras/core/ndarray.cpp: In function ‘boost::python::api::object sdcpp::from_ndarray_impl(const sdcpp::ndarray&) [with T = cv::Scalar_<double>]’:
package/extras/core/ndarray.cpp:601:1: instantiated from here
package/extras/core/ndarray.cpp:546:9: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘Py_intptr_t {aka long int}’ [-Wformat]
package/extras/core/ndarray.cpp: In function ‘boost::python::api::object sdcpp::from_ndarray_impl(const sdcpp::ndarray&) [with T = cv::Range]’:
package/extras/core/ndarray.cpp:604:1: instantiated from …我想拆分u"an arbitrary unicode string"成300字节的块而不破坏任何字符.字符串将写入一个期望utf8使用的套接字unicode_string.encode("utf8").我不想破坏任何角色.我该怎么做？
我正在Display::fmt为我自己的struct 实现一个自定义的自定义.
struct Range<T> {
lower: Option<T>,
upper: Option<T>,
}
范围可以是Range { lower: Some(1), upper: None },这意味着它包含从1到无穷大(或i32我想象的极限)的所有整数.
我想实现Display::fmt使用T's Display::fmt如果绑定不是,None并显示一个空字符串否则:
let range = Range { lower: Some(1), upper: None }
println!("{}", range); // Prints <1,>
let range = Range { lower: Some(1), upper: Some(10) }
println!("{}", range); // Prints <1,10>
let range = Range { lower: None, upper: Some(10) }
println!("{}", range); // Prints <,10>
我已经开始实现了,但是在match表达式和生成的字符串的生命周期方面遇到了麻烦 …