# List randomizer

## List randomizer

**List randomizer**

A list randomizer is a tool or algorithm that takes a list of items and rearranges them in a random order. This can be useful in a variety of situations where a random selection or sequence is needed, such as in random sampling for statistics, generating random test data, or creating random playlists.

There are many ways to implement a list randomizer. One common method is to use a random number generator (RNG) to shuffle the indices of the items in the list. This can be done by iterating through the list, generating a random index for each item, and swapping it with the item at the current index. This process can be repeated a number of times to ensure a truly random order.

Another method is called Fisher-Yates shuffle algorithm, which is an algorithm for generating a random permutation of a finite sequence. It was first described by Ronald Fisher and Frank Yates in their book "Statistical tables for biological, agricultural and medical research" (1938) and later popularized by Donald Knuth in "The Art of Computer Programming" (1998). The algorithm works by iterating through the list from the last element to the first and swapping each element with a randomly selected element from the elements that come after it.

A variation of Fisher-Yates shuffle algorithm is Durstenfeld shuffle algorithm which is an in-place implementation of Fisher-Yates shuffle algorithm.

Yet another approach to list randomization is to use a sorting algorithm that has a random comparison function. This can be done by introducing a random factor into the comparison function used by the sorting algorithm, causing it to randomly order the items in the list.

In addition to these methods, there are also libraries and tools available that provide pre-built list randomization functionality. For example, in Python, the random module provides a shuffle function that can be used to randomize a list. Similarly, in R, the sample function can be used to randomly select elements from a list.

List randomization can also be applied to other data structures like arrays, sets, and dictionaries. Depending on the specific data structure and the desired outcome, the implementation of the randomizer may be different.

In summary, a list randomizer is a tool that can be used to randomly order a list of items. There are various ways to implement a list randomizer, such as using a random number generator, the Fisher-Yates shuffle algorithm, or a sorting algorithm with a random comparison function. Additionally, there are libraries and tools available that provide pre-built list randomization functionality.

**Is there a randomizer in Excel?**

Yes, there is a random number generator function in Excel called "RAND()" which generates a random decimal number between 0 and 1. Additionally, there is another function called "RANDBETWEEN(a, b)" which generates a random integer between the numbers "a" and "b". Both functions can be used in formulas to generate random numbers or in combination with other Excel functions to create random lists, sequences, or data.

**What does randomize () do?**

In most programming languages, the randomize() function is used to initialize the random number generator with a seed value. This ensures that the sequence of random numbers generated by the generator is different each time the program is run. Without initializing the generator with a seed value, the sequence of random numbers would be the same each time the program is run.

**How do I randomly select 100 rows in Excel?**

To randomly select 100 rows in Excel, you can use the "RAND" and "RANK" functions in combination. First, add a column next to your data and use the "RAND" function to generate a random number for each row. Then, add another column and use the "RANK" function to assign a rank to each row based on the random number. Finally, use a filter to only show the rows with ranks between 1 and 100.

Here is an example of how the formula for the random number column would look: =RAND()

And here is an example of how the formula for the rank column would look: =RANK(A2,$A$2:$A$1000)

Where A2 is the cell containing the random number for the first row and $A$2:$A$1000 is the range of cells containing the random numbers for all rows in the data set.

Note: The above example uses 1000 rows, you can adjust it to your needs.

**How do I shuffle a list in Excel?**

To shuffle a list in Excel, you can use the RAND() and RANK.EQ() functions.

In a new column next to your list, enter the formula "=RAND()" in the first cell and drag it down to fill the entire column with random numbers.

Next, in another new column, enter the formula "=RANK.EQ(RAND(),$A$1:$A$n)" (where n is the number of items in your list) in the first cell and drag it down to fill the entire column with ranking numbers.

Finally, sort your original list by the rank column in ascending order to shuffle it.

Alternatively, you can use the VBA (Visual Basic for Applications) to create a macro that shuffles the list.

**Can you randomize a list in Google Sheets? **

Yes, you can randomize a list in Google Sheets. There are a few different ways to do this, depending on the size and complexity of your list and the desired outcome.

One simple method is to use the RAND() function. This function generates a random number between 0 and 1, which can be used to sort your list in a random order. To use this method, you'll first need to add a new column to your sheet, and then enter the RAND() function into the first cell of that column. You can then use the Sort feature to sort your list by this new column, which will randomize the order of the rows.

Another method is to use the =shuffle(A1:A) function, this will shuffle the data in the range A1:A.

You can also use the =sort(A1:A,rand()) function this will sort the data randomly on the range A1:A.

Another way to randomize a list is to use the =ArrayFormula(randperm(counta(A1:A))) function, this will return a range of random numbers between 1 and the total number of items in your list. You can then use these random numbers to rearrange your original list.

You can also use the =QUERY(A1:A,"select A order by rand() limit N",1) function, this will randomly select N rows from the data range A1:A.

Lastly, you can also use script to randomize the list. You can write a script to randomly sort the list using the .sort() method and then .random() function.

In conclusion, there are multiple ways to randomize a list in Google Sheets, using different functions and methods depending on the desired outcome and size of the list.

**How do I randomize a list in Google Sheets without duplicates?**

There are a few different ways to randomize a list in Google Sheets without duplicates. One method is to use the "RAND" and "RANK" functions in combination. Here are the steps to do this:

Select the range of cells that contains the list you want to randomize.

In an empty column next to the list, enter the formula "=RAND()" in the first cell. This will generate a random number between 0 and 1.

Drag the formula down to the last cell of the list to generate a random number for each item.

In another empty column next to the random numbers, enter the formula "=RANK(A2,$A$2:$A$1000)" in the first cell, where "A2" is the cell containing the first random number, and "$A$2:$A$1000" is the range of cells containing all the random numbers. This will generate a ranking for each random number, based on its value.

Drag the formula down to the last cell of the list to generate a ranking for each item.

Sort the list by the ranking column in ascending order.

Delete the random number and ranking columns.

Another method is to use the "RANDBETWEEN" function to generate random numbers within a specific range, and then use the "INDEX" and "MATCH" functions to shuffle the list based on these random numbers. Here are the steps to do this:

Select the range of cells that contains the list you want to randomize.

In an empty column next to the list, enter the formula "=RANDBETWEEN(1,1000)" in the first cell. This will generate a random number between 1 and 1000.

Drag the formula down to the last cell of the list to generate a random number for each item.

In another empty column next to the random numbers, enter the formula "=INDEX(A:A,MATCH(B1,C:C,0))" in the first cell, where "A:A" is the range of cells containing the list, "B1" is the cell containing the first random number, and "C:C" is the range of cells containing all the random numbers. This will generate the item in the list that corresponds to the first random number.

Drag the formula down to the last cell of the list to generate a shuffled list based on the random numbers.

Delete the random number column.

You can also use the built in function called ‘=shuffle’ which will randomize the list with no duplicate.

Note that in all these methods, the list will be random each time you open the sheet or recalculate the sheet.

In all these methods, you will get a randomized list without any duplicates.

**How to randomize items in list Java?**

In Java, you can use the Collections.shuffle() method to randomize the items in a list. Here's an example:

import java.util.Collections;

import java.util.List;

List

Collections.shuffle(numbers);

System.out.println(numbers);

This will shuffle the elements in the numbers list and print out the new order.

Alternatively, you can use java.util.Random class to generate random indexes, and then swap the element at that index with the current element.

Random rand = new Random();

for (int i = 0; i < list.size(); i++) {

int randomIndexToSwap = rand.nextInt(list.size());

Collections.swap(list, i, randomIndexToSwap);

}

Both above approach will give you randomized list.