definition

问题 I hope you can help. I am looking for a way to write a function that inserts one item later. Let me show you an example: def general_poly(L): """ L, a list of numbers (n0, n1, n2, ... nk) Returns a function, which when applied to a value x, returns the value n0 * x^k + n1 * x^(k-1) + ... nk * x^0 """ x = 1 res = 0 n = len(L)-1 for e in range(len(L)): res += L[e]*x**n n -= 1 return res I thought I could just give x a value here and once I do general_poly(L)(10) it will be replaced so that x =

问题 I found this line in stdio.h : extern struct _IO_FILE *stdin; Based on this 'extern' keyword, i assume this is just a declaration. I wonder where is stdin defined and initialized? 回答1: It's defined in the source code of your C library. You typically only need the headers for compilation, but you can find the source code for many open-source standard libraries (like glibc). In glibc, it's defined in libio/stdio.c as like this: _IO_FILE *stdin = (FILE *) &_IO_2_1_stdin_; Which is in turn

问题 I'm working with a couple of AI algorithms at school and I find people use the words Fuzzy Logic to explain any situation that they can solve with a couple of cases. When I go back to the books I just read about how instead of a state going from On to Off it's a diagonal line and something can be in both states but in different "levels". I've read the wikipedia entry and a couple of tutorials and even programmed stuff that "uses fuzzy logic" (an edge detector and a 1-wheel self-controlled

问题 I'm trying to figure out how the basic IO Haskell functions are defined, so I used this reference and I got to the putChar function definition: putChar :: Char -> IO () putChar = primPutChar Now, however, I cannot find more information about this primPutChar function anywhere. Maybe it might refer to a pre-compiled function, available as binary from a shared object? If that's the case, is it possible to see its source code? 回答1: What prim* means Since you're asking this question in terms of

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 6 years ago . I feel like developers talk about memory leaks but when you ask them what that means many have no idea. To prevent these situations,

问题 This is probably a n00blike (or worse) question. But I've always viewed a schema as a table definition in a database. This is wrong or not entirely correct. I don't remember much from my database courses. 回答1: schema : database : table :: floor plan : house : room 回答2: A relation schema is the logical definition of a table - it defines what the name of the table is, and what the name and type of each column is. It's like a plan or a blueprint. A database schema is the collection of relation

问题 This code compiles fine: extern int i = 10; void test() { std::cout << "Hi" << i << std::endl; } While this code gives an error: void test() { extern int i = 10; std::cout << "Hi" << i << std::endl; } error: 'i' has both 'extern' and initializer I read this in C++ Primer: Any declaration that includes an explicit initializer is a definition. We can provide an initializer on a variable defined as extern, but doing so overrides the extern. An extern that has an initializer is a definition. It

问题 My assignment asks me to access a test.txt document, so the file name has to be hard coded to my C drive. I have no idea what hardcoding means. Can somebody please help me with this? 回答1: "hard coding" means putting something into your source code. If you are not hard coding, then you do something like prompting the user for the data, or allow the user to put the data on the command line, or something like that. So, to hard code the location of the file as being on the C: drive, you would

问题 My assignment asks me to access a test.txt document, so the file name has to be hard coded to my C drive. I have no idea what hardcoding means. Can somebody please help me with this? 回答1: "hard coding" means putting something into your source code. If you are not hard coding, then you do something like prompting the user for the data, or allow the user to put the data on the command line, or something like that. So, to hard code the location of the file as being on the C: drive, you would

问题 It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center. Closed 6 years ago . I'm a beginner user for Python, but I get confused between literal and variables. This is what I know about a literal: "a"+"b" And variables: sentence="a"+"b" 回答1: A literal is notation for representing a fixed (