Advertisements I’m working with a list in Python and I need to extract elements with indices from 0 to 3 and from 5 to 7 ([0:3] and [5:7]). It could be done by using slicing and concatenation: target_list = [1, 2, 3, 4, 5, 6, 7, 8, 9] subset_indx = list(range(3)) + list(range(4, 7)) subset_list… Read More Subset a list with two non-consecutive slices in Python
Advertisements What’s Python’s equivalent to R’s layout() function which can create a plotting grid of any shape? Consider the following 3 figures made by layout(): set.seed(123) layout(t(matrix(c( 1, 1, 2, 2, 3, 3, 4, 5, 5, 6, 6, 7 ), ncol = 2)), widths = rep(1, 6), heights = rep(1, 2)) par(mar = c(4, 5,… Read More Python equivalent to R's layout()
Advertisements this is my first question on StackOverflow ! 🙂 To be honest I’m about to destroy my whole setup. My code is making me crazy. My problem is, I am not able to fill a dynamic array with the return of a function. My goal here is, for each array box, fill it with… Read More Attribute return of a function to an array
Advertisements Hi I’ve been learning ReactJs and I wrote these lines: handlerClick(i) { this.setState( (state) => (state.squares = […state.squares, (state.squares[i] = "X")]) ); } Now, I know whats happening but I’m confused with how this is working, the order that each operation is being executed… >Solution : Regarding the order of operations, everything to the… Read More Can someone explain how this state update is resolved?
Advertisements from itertools import permutations,product,combinations_with_replacement colours = [‘r’,’g’,’b’] y = list(product(colours,repeat =2 )) x = list(combinations_with_replacement(colours,2)) print(y) print(x) I understand permutation of a set of objects is an ordering of those objects. When some of those objects are identical, the situation is transformed into permutations with repetition. >Solution : This may provide some insight: colours… Read More What is the relationship between the product function and the concept of permutations with repetitions?
Advertisements I think the two commands below should be identical, but given the heredoc, the shell produces an error. Is it possible to pass a heredoc to the -c argument of sh? heredoc example /bin/sh -c <<EOF echo ‘hello’ EOF # ERROR: /bin/sh: -c: option requires an argument simple string example /bin/sh -c "echo ‘hello’"… Read More sh -c doesn't recognize heredoc syntax
Advertisements I’m trying to find the equivalent of tidyr::unnest() for a data.table with multiple nested columns: MT <- as.data.table(mtcars) MT_NEST_MULT <- MT[, .(data1 = .(.SD[, .(mpg, hp)]), data2 = .(.SD[, !c("mpg", "hp")])), by = .(cyl, gear)] cyl gear data1 data2 8 3 <S3: data.table> <S3: data.table> 8 5 <S3: data.table> <S3: data.table> 6 4 <S3:… Read More Un-nesting multiple columns with data.table in R
Advertisements I would like to delete all data after row [x]. For example if the x = 355, I want all data to be deleted after 355th row. I am able to delete all content in a simple sheet in google spreadsheet with: var sheet = ss.getSheetByName(‘foo’); sheet.clearContents(); I’ve tried to do it with getRange… Read More How to clear/delete data after a given row index in Google Spreadsheets
Advertisements In the delete function, the else part is executed every time even after the if statement is true. How can I solve that problem? #include<stdio.h> #include<stdlib.h> #define MAX 10 int front=-1,rear=-1; int Q[MAX]; void insert(); void delete(); void display(); void peek(); int main(){ int n; while(1){ printf("Enter your operation:-\n1.Insert\n2.Delete\n3.Peek\n4.Display\n5.Exit\n"); scanf("%d",&n); switch(n){ case 1: insert();… Read More "else" block is executed every time even after the "if" statement is true
Advertisements I have a preprocessor directive that I do not set, so I cannot change it, it is either true or false. Normally I would have done : #ifdef DIRECTIVE // code #endif But this will always run, since DIRECTIVE is always defined. Is there a way that I can do basically the equivalent of:… Read More Can I test the value of a preprocessor directive?