Programmer Group

OS version: RT thread 4.0.0 Chip: STM32F407 The following is the reference provider provided by the official ADC Access ADC device The application program accesses the ADC hardware through the ADC device management interface provided by RT thread, and the relevant interfaces are as follows: function describe rt_device_find() Find dev ...

timeit module The timeit module can be used to test the execution speed of a small piece of Python code. class timeit.Timer(stmt='pass', setup='pass', timer=<timer function>) Timer is a class that measures the execution speed of small pieces of code. The stmt parameter is the statement to be tested; The setup parameter is the setting ...

First of all, we need to install the docker environment. This is relatively simple. Take centos7 as an example. docker needs kernel version 3.10 + to install on centos7. You can check the kernel version number through uname-r. if the version does not match, please consult the data for replacement. When you are ready, use the following command t ...

Source address: https://github.com/AFNetworking/AFNetworking/tree/0.2.1 First, add the corresponding library to your Demo, set the MRC and set the new syntax according to the prompts, so that the project can run: Including support for HTTP: 1. Add NSAppTransportSecurity type Dictionary in Info.plist; 2. Under NSAppTransportSecurity, add nsallow ...

https://www.luogu.org/problemnew/show/P1074 Obviously, it's dfs, and there's no pruning and memorization, but preprocessing is troublesome I use three two-dimensional arrays to store the state: visx[x][i] represents whether row x is selected or not, visy[y][i] represents whether column y is selected or not, visg[g][i] represents whether the n ...

Portal I read the solution of the problem Given the order of point pairs, it is easy to think of topological ordering. But if you sort by dictionary order, you will encounter smaller ones in front, The counter examples can be cited: four dishes, limited to < 2,4 > < 3,1 >, Then the least lexicographic order is 2,3,1,4, but the ...

J2Cache is a two-level caching framework currently being used by OSChina. First level cache usage Ehcache , second level cache uses Redis  . Because a large number of cache reads will cause L2 network to become the bottleneck of the whole system, the goal of L1 is to reduce the number of L2 reads. This caching framework is mainly used in ...

Next is the configuration of multi page application. After installing vue 3.0, you can find that the directory is much smaller than that of 2.0, public is equivalent to the original static. index.html is the entry of the project. src is the same as before. Cli 3.0 has no build or config. If you want to configure, you need to create the vue.c ...

First, introduce some basic operations of SQL database: 1 create 2 delete 3 write 4 update (modify) 5 condition selection With the above basic operations, you can establish and store a simple database.   Release the code called by python: here is calling dos to operate the database, which is not as simple as the following # -*- coding: u ...

Question introduction: slam builds the map, first reduces the line sampling, then carries on the visualization or the storage. However, after downsampling, the point cloud data is scattered into a mass without error. Show the code and point cloud data as follows, pcl::VoxelGrid<Lidar::PointType> voxel_filter; voxel_filter.setLeafSize ...