# Iteration Questions

## Fastest way to get dot product of a matrix and each point in the given array

I have an array nx3 of n points, each one has x, y and z coordinate. i need to rotate each point, so i have the rotation matrix 3x3. to do this, i

## Fastest way to count frequencies of ordered list entries

I'm counting the occurrences of non-overlapping grouped subsequences of length i in a binary list, so for example if i have a

## I want to search for values in binary search tree using iteration

Hello i wrote this method to search for values in my binary search tree but it is always returning false whether the value is found in my bst or

## Is it possible to iterate over a list of lists and print out the name of the lists in addition to their contents?

I am trying to print out out the ticker symbol next to its two respective values within my nested list. gme_infos = [45.95, 133.46]

## "dictionary changed size during iteration" while updating a list of dictionaries

I have a list of dictionaries, which looks like this: car_list = [ {'toyota': '{name}/toyota'}, {'mazda': '{name}/mazda'},

## Apply Iteration on the each element in the vector with a time delay

I have a vector having 8 elements , i want each element ot be itertated from initial state "30.9" and after every 1 second it is changed from 0 to

## Why map or reduce keeps running without any condition given?

Const array = [7, 2, 4, 1, 10, 6, 5, 11] const max = array.reduce((acc, val) => { console.log(val, acc) return val >

## Mergesort Implementation gone wrong

Output not as expected import random def mergesort(a): width = 1 n = len(a)

## Is there a way to rotate values in a list but every 3rd position on the list is stationary?

For some homework, my teacher decided to give us a coding challenge that she couldn't work out herself. the challenge was that given a list [1, 2,

## Reactjs map function - iterate json object

I'm trying to fecth data from db.json dispay it in cards. there are two objects in details array so

## How can I iterate through an excel sheet to perform a search on a webpage Python Selenium

I want to iterate through a list of companies to search them one by one and save the href. from selenium.webdriver import firefox

## R : How to iterate sum across multiple columns?

I am trying to iterate/loop a sum across multiple non-consecutive columns. my objective is to compute the subscale score of multiple

## Looping through a nested list and summing all elements of each internal list in python

My problem is as follows: i have a list of lists named 'all_slips.' i would like to loop through each of the lists within the list and sum all of

## Python - Problem with loops while comparing two lists

I have a little problem, i am trying to compare 2 lists with words in it to establish a similarity percentage but here is the thing, if i have the

## React - Conditional rendering ( iteration from multiple arrays )

Hi guys currently i have a problem on conditional rendering in react. i have 2 arrays saved in state : this.state = {

## Push HashMap Values Into Firebase Under The Same Node

I am trying to loop through a hashmap and enter the data into the same node, however the code is pushing data into new nodes.

## How to apply a function to all the columns in a data frame and take output in the form of dataframe in python

I have two functions that do some calculation and gives me results. for now, i am able to apply it in one column and get the result in the form of

## How can I save the 'previous' and 'next' iteration of an object in a loop?

I am working on a program that grabs a number before, and after an incidence of a string and then compares those numbers - but it can only happen

## NodeJS : Loop through nested JSON and remove elements based on a condition

Let's say i have a below object: { "schema": [ { "field": "name", "type": "string", "enabled": true }, { "field": "age",

## Python create combinations of dictionary

I would like to convert a python dictionary of the following form: d = {'a':[1,2,3], 'b':[0.1,0.5], 'c':[10,20]}

## Map addAll Overwrite in For-Loop Dart

I have problem with map iteration. i tried this list testlist = []; map<string, dynamic> testmap = new map; for (var i

## How to delete properties recursivley from object based on key/value

I'm trying to delete certain children of an object based on whether their "size"-key has a value of 0. i'm using the npm package

## React - Check for spaces in string when iterating with Object.keys.map

I'm using anime.js to do some animation on a site i am building. right now i am trying to animate a string of a few words. i have the

## How to concatenate datafiles in a loop?

Here is the script and i would like to put it in a loop as the number of files (n) will change every time: coef = 1000 data1 =

## Creating multiple descriptive tables (with a loop) and storing as dataframes in R

I am trying to create a simple 'for loop' to produce a series of descriptive tables (saved as dataframes) using r but am struggling to do so.

## How can I iterate using a single 3 indexed list instead of 3 nested loops?

I am working on a project in python which requires me to do iteration over a 3-element list as; for i in range(0,10): for j in

## How to Iterate through a 2D array step by step using a button?

I have to iterate through a 2d loop step by step after pressing a button in android, lets say 3 4 3 4 5 4 2 3 4

## How to export list values to CSV file in one row..?

I have a list like this: name_cl = ['lolo', 'fadli', 'jori', 'andi', 'budi', 'dedi', 'nori']

## Adding extra component in map iteration gives error

I am new to react. i have following iteration where i am adding number of <td> <tr key={rowidx}>{

## Reassigning value of iterator while iterating through it

first of all a disclaimer: i don't want to use a code like this, i am aware it is a bad practice. as well i

## Comparing with adjacent values in Python

I want to compare the minimum value of each row with the nearby elements. for example, min of first row occurs at pe[0,1]. i want to compare this

## How do we use 'and' operator in array indexing?

I found one code that used a[i][j] += min(a[i - 1][j and j - 1:j + 2]) i tried similar implementation as shown below which gave me

## How can I get specific object key in map iteration

I have one json file and i iterate it with map but i have a deep object key with name 'content' and i want to get specific key from it when i

## Efficient iteration to create df columns based on newly created columns (alternative to loop)

I need to create multiple columns in a data frame based on the new columns. for this aim, i have a loop that works fine but requires quite a lot

## Updating value at each iteration using python

I want to get updated value of pw at each iteration. for first iteration, it takes minimum value of first row and subtracts from pw1. for second

## React - "Is not a function" error when passing function as props to functional component

I'm relatively new to react and i'm working on a todo list style recipe

## Faster methods than iterrows with conditions (predecessor and successor of each row)

I have the problem that the code from below is extremely slow. i haven't been working with python and pandas that long, so i don't know exactly

## Iterate over list

Q6 4;99 3;4;8;9;14;18 2;3;8;12;18 2;3;11;18 2;3;8;18 2;3;4;5;6;7;8;9;11;12;15;16;17;18 2;3;4;8;9;10;11;13;18 1;3;4;5;6;7;13;16;17

## node wait for iteration to complete before callback

I have a lambda function in node.js to send a push notification. in that function i need to iterate through my users sending a

## Change "-" to "C" in all files within directory

I have some files that looks like this:

## Can someone explain me why we used curly braces "{}" in this code?

While i was trying to check how many times an element used in an array, i found this code. it is written by another user and i got it to work but

## NoneType-Error with yield in Python

I've got a problem with the yield and generator thing in python, hope you might know the solution here's my code (very simplified)

## Print the length of the longest continuous sequence (Python)

Here's the question:

## How to zip unequal lists as a product of first list with others?

I have multiple lists like following- list1=['tom'] list2=[16] list3=['maths','science','english'] list4=['a','b','c']

## Iterate over every nth element in string in loop - python

How can iterate over every second element in string ? one way to do this would be(if i want to iterate over nth

## How to get the correct results from the for loop in Python 3?

I am making a simple program where there is a simple for loop. there are two inputs in my program, n and

## different run results between python3 and python2 for the same code

When i run this python code in python3 it shows different results from python2? why there are different values? d = 0 x1 =

## What is n= n ^1U<<i?

The problem i am facing here is to understand the change in the value of n in each iteration of the loop. if you explain it by

## Going Through Users in Database Individually

I have been searching and searching for help on this question, but i have found no luck. i am wanting to have a page that displays each user in my

## Problem aligning U.I elements using a foreach loop on multiple arrays in Laravel Blade file

Am working on a laravel application whereby am fetching some data from the backend and storing in 3 separate variables.next i pass the variables

## What is the difference between an iteration and a loop?

I am doing cs50 harvard university online and i'm on week 3 but while watching the video i noticed that i iterations and loops seem the same, as

## React: Iterating through deeply nested objects and displaying them without tearing my hair out

I have an api returning data in a deeply nested objects within an object within an object format. i am attempting to grab data from some of these

## Cant seem to iterate over a column to assign sentiment values

I have tried iterating over rows in my dataframe to get sentimental values. my code is: from nltk.sentiment.vader import

I tried some other solutions to this like using asmap() and foreach but kept getting different errors. like it was

## How can I convert this C algorithm from recursive to iterative?

You are all so stupid to dislike when the question is intelligent and the person who has answered is equally intelligent how can i convert

## Python: Combined lists iteration

I've got two lists: synonymes = ['verb1', 'verb2', 'verb3'] phrases = ['blabla verb blabla', 'blibli verb

## Dart / Flutter: Error "Stream has already been listened to." && "await for" inside fa "for loop" fails

Aye aye good people, i'm probably missing something here: this code is fictional (it's an oversimplification, for everyone

## How do you calculate negative powers in C using iteration?

I'm writing a function in c that takes in a float base and int power, and calculates base^power so far i have: float

## Iterate through an array of characters in C

Recently i saw this while loop condition in c in the example below but i have no idea what the while condition really means and how the compiler

## How would I convert this recursive function to an iterative one?

I'm having trouble trying to convert this recursive function find_reachable(..) to it's iterative equivalent. i have looked around

## delete occurrences of an element given after its k-th occurrence in a linked liste

I wanted to write an algorithm that start to delete occurrences of an element given after its k-th occurrence, but the one that i have built

## Add item back to for loop

I am working on some code, and i cannot figure out how to create the behavior that i want. i want to iterate through a list, and pull some data.

## Shift through an array sequentially in C

I have a matrix that i am trying to "count" through by shifting the first row to the left n number of times until it is in its original position,

## I am trying to add vectors in a for loop, but after 2 iterations I get an incorrect answer (C)

I am trying to implement the iterative formula xn+1 = t*xn + c, for a given number of iterations i. here x and c are vectors and t is a 3x3

## Iterate through/compare values in arrays and print string based on result, IndexError: out of bounds

Trying to create a win/loss/tie list based on team scores. my attempt: #import numpy import numpy as np #create array for week

## For loop and open statements

I understand why the first for loop works; that loop is essentially looping through a list, as per the readlines()

## Modify list and dictionary during iteration, why does it fail on dict?

Let's consider this code which iterates over a list while removing an item each iteration: x = list(range(5))

## Iterating over two lists and removing a value on condition in Kotlin

I have a list of time slots of an hour each and a list of slot bookings stored in firestore for the same day. i now need to show availability of

## Can I use keySet to modify HashMap during iteration?

I know that collections shouldn't be modified during iteration. so we should have workaround. i have a code: map<key,

## Cannot get the first element of array whereas map() works as a charm

In a react component want to print out the a value of an object ("name") which is the first element in the array:

## Illuminate - HasMany - Iteration

i am just doing my first exercises with illuminate (laravel) on my currently handmade database and website. i would like to improve by using

## In an ANT build.xml file, how can I iterate over the items in the \${env} variable?

This is in a windows xp environment. i'm trying to install and edit some files that have default settings. i want to update these

## Python iterrate on two keywords object

Backgound i want to generate random numbers with distributions(np.random.normal, np.random.poisson, etc.),

## Iteration over HTML sections

I want to iterate over three elements in my html, changing the attributes in each section, one section at a atime. i thought i'd get a nodelist

## How to iterate json consists of array elements

I am getting this object : "contributiondata": { "contribution 1": [ 4, 4

## concatenate all properties of 2 similar objects javaScript

I have 2 different objects, with the same properties which i want to concatenate: obj1 = {id: "1: identifier 1 \n", description:

## python iterate over class variables and only get values of variables

I want an enumerator class which has class variables with same values such as: from enum import enum class cars(enum): bmw =

## Python3 StopIteration Error can not raise when using list(map(...))

At first i write this, and it raises stopiteration, works well. it = iter([1]) iters = [it] * 2 for it in iters: r = next(it)

## Laravel Foreach Looping

I need to display the previous value of the iterated array, here is code <tr> <th></th>

## how to store all the values of a list of lists and the frequence of their appearance as well as their index?

My code is this idnt=[] idntfrq=[] for i in range(len(occ)): idnt.append([]) idntfrq.append([])

## Looking to iterate through list of lists that skips over specific indices

I'm currently working on a python 3 project that involves iterating several times through a list of lists, and i want to write a code that skips

## Specific statement every N iterations in Python

I want to create a loop that for every 12 months, the 'year' variable should increment by 1 until reach the limit. i couldn't make it on my own.

## Iterating over lists in pandas dataframe to remove everything after certain value (if the value exists) in list

I want to filter my dataframe values based on the occurrence of '1' in my column events. when a 1 occurres, everything after the 1 should be

## How to do something else at the end of an iteration

I have a list that contains some strings , i want to add some predefined values before every string in a list but the value at the end of the

## How to read a specific column of a row from a csv file in java

I have the following code which reads the data from the csv file, it iterates over the rows but i don't manage to figure out how to iterate over

## Array of dates want to be use in paramater ( year calendar bootstrap) (customDayRenderer)

So i have an option named customdayrenderer var reddatetime = new date(currentyear, 2, 13).gettime(); \$('#calendar').calendar({

## Trying to Split One List into Multiple Lists Inside of a Main List - Python

For some reason i get this traceback when trying to split comma delimited items into a new list and then inserting them into a higher list:

## how do I advance to the next item in a nested list? Python

Working with a couple of lists, iterating over each. here's a code segment: self.links = [] self.iter=iter(self.links) for tgt in

## Check nested Array values, if a match: combine data from both

I have a weird situation, and i'm not totally sure if my solution is going to work, or is possible... it's for a wordpress site, but i'm hoping

## I want to type in english in one text box and want converted text in Arabic into another text

My requirement is clear ... i want to type in english in one text box and want converted text in arabic into another text and if i edit first text

## can't loop more than once - for loop (python)

The task here is : a. match_ends given a list of strings, return the count of the number of strings where the string length is 2 or more

## How to setAttribute on React JSX element dynamically?

I want to set key attribute on react element dynamically, like below. however both approaches do not work. i know i can use other

## Nested loop involving date manipulation in Javascript

I'm working on a booking system whereas the price depends on seasons and those seasons are recurring yearly. so far everything works well except

## Sum of all Nodes Iteratively - Not Recursively - Without 'left' and 'right'

I have this binary tree structure: # a node is an object # - value : number # - children : list of nodes class node: def

## Why does Python's iter() on a mapping return iterkeys() instead of iteritems()?

It seems like if you want to get the keys of a mapping, you ask for them; otherwise, give me the whole mapping (constituted by a set of

## how do I merge items from a dataframe into a query?

I have a dataframe like this:

## Laravel foreach only returns first value

First please be gentle i am a beginner and only prectising, i have a problem, i would like to get laravel's language files and edit their

## How does the "this" keyword work with objects in JavaScript?

Since i'm trying to grasp the concept of iterables in javascript, i built one with the following code: let range = { from: 0,