Category : templates

I would like to modify some code when I calculate the nromal in PCL, for example. Like pcl::NormalEstimation<pointT, pcl::Normal> ne_tgt; ne_tgt.setInputCloud(cloud_tgt); pcl::search::KdTree<pointT>::Ptr tree_tgt(new pcl::search::KdTree<pointT>()); ne_tgt.setSearchMethod(tree_tgt); pcl::PointCloud<pcl::Normal>::Ptr cloud_tgt_normals(new pcl::PointCloud<pcl::Normal>); ne_tgt.setRadiusSearch(0.1); ne_tgt.compute(*cloud_tgt_normals); So, I try to modify the computefeature in compute, but the index failed. I don’t know where I can modify. Some code in pclfeaturesincludepclfeaturesimplfeature.hpp is ..

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I am trying to extend std::span to have a bounds checked operator[] (I am aware gsl::span provides this) I have declared my container as follows: #include <span> #include <string> #include <utility> template <typename … TopArgs> class BoundsSpan : private std::span<TopArgs…> { public: typename std::span<TopArgs…>::reference operator[](std::size_t idx) const { if (idx >= this->size()) [[unlikely]] { throw ..

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I’m new to c++ and template and want to write a metafunction that converts class A to class B while persisting all operators and keywords (C++17/20). For example, some_func<const A*, A, B> generates const B*, some_func<A*&&, A, B> generates B*&&. some_fun should be valid no matter how many */&/const provided. I’d be appriciated if someone ..

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I’m trying to make a function template in a header file that accepts a generic function pointer and packed arguments. The function template would invoke the received function pointer using the packed arguments. My goal is to calculate and return the execution time of the function pointer. #ifndef LOGTIME_HPP #define LOGTIME_HPP #include <chrono> #include <ratio> ..

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I am attempting to create a simpe input() function in C++ similarly to Python. I expected the code (below) to prompt the user for their age, then to print it into the console. Instead it gives me the following error message: In function ‘int main()’: 17:36: error: no matching function for call to ‘input(const char ..

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