function

问题 This post shows how to axiomatise a length function for Z3's built-in lists. However, the function is sort-specific (here Int) and not applicable to lists of bools or custom sorts. ; declare len as an uninterpreted function (declare-fun len ((List Int)) Int) ; assert defining equations for len as an axiom (assert (forall ((xs (List Int))) (ite (= nil xs) (= 0 (len xs)) (= (+ 1 (len (tail xs))) (len xs))))) What would be the smartest way of encoding sort-generic list functions? (If I remember

问题 I'm working on my intro C course assignment and I'm tasked with the following... Write code for a function that receives two parameters (a,and b) by value and has two more parameters (c and d) by reference. All parameters are double. From main, use scanf to get two numbers, then call the function, and then display both returned values to the output in a printf statement. The function works by assigning (a/b) to c and assigning (a*b) to d. While my knowledge is basic, I believe I understand

问题 I'm working on my intro C course assignment and I'm tasked with the following... Write code for a function that receives two parameters (a,and b) by value and has two more parameters (c and d) by reference. All parameters are double. From main, use scanf to get two numbers, then call the function, and then display both returned values to the output in a printf statement. The function works by assigning (a/b) to c and assigning (a*b) to d. While my knowledge is basic, I believe I understand

问题 In Python, I need to call many very similar functions on the same input arguments sampleA and sampleB . The only thing is that some of these functions require an option to be set, and some don't. For example: import scipy.stats scipy.stats.mannwhitneyu(sampleA, sampleB) [...some actions...] scipy.stats.mstats.ks_twosamp(sampleA, sampleB, alternative='greater') [...same actions as above...] scipy.stats.mstats.mannwhitneyu(sampleA, sampleB, use_continuity=True) [...same actions as above...]

问题 I am trying to make the Iteratee structure generic so I can pass in a different parsing function and get an different Iteratee . This is the non-generic version that works: use std::io::{BufRead, BufReader}; use std::str::{from_utf8, Utf8Error}; #[derive(PartialEq, Debug)] struct Cat<'a> { name: &'a str, } fn parse<'a>(slice: &'a [u8]) -> Result<Cat<'a>, Utf8Error> { from_utf8(slice).map(|name| Cat { name: name }) } struct Iteratee<R> where R: BufRead + Sized { read: R, } impl<R> Iteratee<R>

问题 I have some JavaScript code I found online that provides stats to google analytics for my HTML5 video. The code however only CORRECTLY displays stats for "video played" and "video paused" but the rest of the information won't display or even calculate. The rest of the info is: "25% video watched", "50% video watched", "75% video watched", "100% video watched". How can I get the code below working properly? Also, is google analytics the only way to track these stats or is there another way?

问题 What's the difference between these? I know that their type signatures are different, and that all functions start off normal and have to be .tupled to get their tupled form. What's the advantage of using un-tupled (but non-curried) functions? Especially because it seems to me that passing multiple arguments to a tupled function automagically unpacks them anyway, so by all appearances they are the same. One difference i see is that it forces you to have types for every number of function

问题 I'm really puzzled with Javascript this time: var x = Array.prototype.concat.call; typeof x; // function x(); // Uncaught TypeError: x is not a function What on earth is going on here? If it helps, I also noticed: x([1,2],[3,4]) does not work either toString also thinks it's a function: Object.prototype.toString.call(x); // "[object Function]" This also happens with Array.prototype.concat.apply . When it is forced as an expression it also does not work: (0, Array.prototype.concat.call)([1,2],

问题 I want to calculate the mean of column of all the csv in one directory, but when I run the function it give me the error of "Error in numeric(nc) : invalid 'length' argument". I believe that CSV files have n/a value but it shouldn't affect the calculate the number of column? pollutantmean <- function(directory, pollutant, id =1:332, removeNA = TRUE){ nc <- ncol(pollutant) means <- numeric(nc) for(i in 1:nc){ means[i] <- mean(pollutant[, i], na.rm = removeNA) } means } So here is my update

问题 I have a list like [2,3,4,5] and i want square of these number using python function Have tried below Python code def square(list=[]): for i in list: new_value=[] new_value.append(i**2) return new_value I get the square of only first entry in a list. square(2,3,4) 回答1: List comprehension makes this function a single liner and much clearer. def square(x): return [y**2 for y in x] 回答2: Your method square is initialising new_value for every element in the list, and also your return is