max

问题 Consider a class A having a member x and a std::vector< A >. Now its a common task to search for the maximal x among all elements inside the vector. Clearly I can only use std::max_element if there is an iterator on the x's. But I must write one by my own, or I just make a simple for loop. maxSoFar = -std::numeric_limits< double >::max(); for( std::vector< A >::const_iterator cit = as.begin(); cit != as.end(); ++cit ) { if( cit->x > maxSoFar ) maxSoFar = cit->x; } but it's so tedious, and I

问题 This question already has answers here : #define NOMINMAX using std::min/max (4 answers) Closed 4 years ago . This line of code fails to compile in VS2015 Update 3: auto a = std::numeric_limits<long long>::max(); It cannot find the definition of max() . Why is this? 回答1: That max call may interfere with "evil" max preprocessor macro defined in the Windows SDK headers, that you have probably included (directly or indirectly). An option is to prevent the preprocessor max macro to kick in, using

问题 The data below have an IndID field as well as three columns containing numbers, including NA in some instances, with a varying number of rows for each IndID . library(dplyr) n = 10 set.seed(123) dat <- data.frame(IndID = sample(c("AAA", "BBB", "CCC", "DDD"), n, replace = T), Num1 = c(2,4,2,4,4,1,3,4,3,2), Num2 = sample(c(1,2,5,8,7,8,NA), n, replace = T), Num3 = sample(c(NA, NA,NA,8,7,9,NA), n, replace = T)) %>% arrange(IndID) head(dat) IndID Num1 Num2 Num3 1 AAA 1 NA 7 2 BBB 2 NA NA 3 BBB 2 7

问题 The data below have an IndID field as well as three columns containing numbers, including NA in some instances, with a varying number of rows for each IndID . library(dplyr) n = 10 set.seed(123) dat <- data.frame(IndID = sample(c("AAA", "BBB", "CCC", "DDD"), n, replace = T), Num1 = c(2,4,2,4,4,1,3,4,3,2), Num2 = sample(c(1,2,5,8,7,8,NA), n, replace = T), Num3 = sample(c(NA, NA,NA,8,7,9,NA), n, replace = T)) %>% arrange(IndID) head(dat) IndID Num1 Num2 Num3 1 AAA 1 NA 7 2 BBB 2 NA NA 3 BBB 2 7

问题 I have a two dimensional integer array. Row and Column information (locations of numbers) is important for me. So, I don't want to sort an array (matrix actually). How can I find the highest 5 value from this two dimensional array? Here is my code: for (int row = 0; row < matirx.length; row++) { for (int col = 0; col < matirx[row].length; col++) { if (matirx[row][col] > maxValue) { maxValue = matirx[row][col]; } } } 回答1: First, I went for a streams solution that is very similar to other

问题 I was looking at the code of numpy.argmax function. I am confused which data structure numpy maintains for the argmax function. https://numpy.org/doc/stable/reference/generated/numpy.argmax.html Eventually, I want to know what is the theoretical average case running time complexity of numpy argmax function for primitive data types. Is it O(logN) or O(N) in the average case? This may be a relevant question as well: Faster alternatives to numpy.argmax/argmin which is slow Thanks in advance. 回答1

问题 I have a df: dog1 dog2 cat1 cat2 ant1 ant2 0 1 2 3 4 5 6 1 1 2 3 4 0 0 2 3 3 3 3 3 3 3 4 3 2 1 1 0 I want to add a new column based on the following conditions: if max(dog1, dog2) > max(cat1, cat2) > max(ant1, ant2) -----> 2 elif max(dog1, dog2) > max(cat1, cat2) -----> 1 elif max(dog1, dog2) < max(cat1, cat2) < max(ant1, ant2) -----> -2 elif max(dog1, dog2) < max(cat1, cat2) -----> -1 else -----> 0 So it should become this: dog1 dog2 cat1 cat2 ant1 ant2 new 0 1 2 3 4 5 6 -2 1 1 2 3 4 0 0 -1

问题 I've spent a long time looking around for a solution for this and not found quite what I want. Efforts to adapt existing solutions for different problems have also not worked! I am using LookupSet to return a list of dates, then joining them to return a list: =Join(LookupSet(Fields!cPatSer.Value,Fields!cPatSer.Value,Fields!DDate.Value,"PatD")) I want to only show the most recent date from that list. Here is what I have tried so far: The above function wrapped in a Max function (doesn't work

问题 I would like to assign the max value of a group to all rows within that group. How do I do that? I have a dataframe containing the names of the group and the max number of credits that belongs to it. course_credits <- aggregate(bsc_academic$Credits, by = list(bsc_academic$Course_code), max) which gives Course Credits 1 ABC1000 6.5 2 ABC1003 6.5 3 ABC1004 6.5 4 ABC1007 5.0 5 ABC1010 6.5 6 ABC1021 6.5 7 ABC1023 6.5 The main dataframe looks like this: Appraisal.Type Resits Credits Course_code

问题 I write something like this in Ruby: if a.max == a[0] brand = b[0] elsif a.max == a[1] brand = b[1] elsif a.max == a[2] brand = b[2] elsif a.max == a[3] brand = b[3] end a and b both are unique arrays. Is there any way to check all if and elsif 's in the same condition? Only one condition for a[0] , a[1] , a[2] and a[3] ? 回答1: Array#index might help in cases like these (assuming the size of a and b is the same): brand = b[a.index(a.max)] In cases in which the array a might be empty, you will