# Questions tagged [random-number-generator]

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### Does RNGD accept other entropy input with Debian11, kernel Debian-5.10.0-17?

Aug 06, 2022 I upgraded to the Debian-5.10.0-17-amd64 kernel recently and was not impressed. I regressed back to the Debian-5.10.0-9-amd64 kernel. Under the '9' kernel, I run a script that cat's ...
15 views

### how to make random value in range a-z with python [migrated]

i have python code which it will generate random value like JAY5uFy4F this is the first output when i run python script this is my code: a= [] n=1 c=1 c2=3 Start= 10**(n-1) End= (10**n)-1 while 1 : ...
82 views

### Excel RAND incrementing numbers

I have two numbers in excel a min and max and I want to fill in a random number between those two numbers but it must increase each time thinking something like INT(RAND()+C3) and c3 has a value of ...
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82 views

### How do I get real random in CMD?

I have some script which every PC in network download and execute, and the task is NOT to run script simultaneously. So, I used simple pseudo-random for timeout like TIMEOUT /T 2%random:~0,2% But as ...
1 vote
223 views

### Will two RAND() functions in the same formula produce two separate random numbers?

I am reviewing someone else's work without them being easily able to answer. The formula below should not produce results less than zero as it is related to a physical quantity that cannot be negative....
52 views

### Why do we use pseud-random numbers when we have access to truly random numbers easily? [duplicate]

Is there any reason except being able to reproduce the same sequence of numbers, for using pseudo-random number generators while there is easy access to truly random numbers such as the number of ...
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119 views

### Run two function inside a loop in VBA

I have this formula for creating random number =DEC2HEX(RANDBETWEEN(100,1000),8) in my excel sheet. But I want to convert it to vba. After a lot of hassle I came to this : ActiveSheet.Range("A&...
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788 views

### vba code for generating unique number in a column's cell serially

I created a button in my excel sheet. Now I want that every time I click on that button an unique code will be generated in a cell. Again if I click on that button another unique code will be ...
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596 views

### How reliable is the randomness of the shuf command?

I ran the following command to generate 1 billion random numbers: time shuf -i 1-1000000000 > "SHUF TEST 1" To my surprise it was able to do this in less than 10 mins. I then ran the ...
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118 views

### Can the “/dev/random” device be edited to make the RNG predictable on my computer? [closed]

Is it possible, with super user access, to edit my /dev/random or /dev/urandom in such a way that even OS-generated random numbers are predictable? I am trying to understand if I sent an executable (e....
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30 views

### convert decimal random values to binary for ent testing

I have ascii random values from /dev/urandom in a file like: 435 678 437 897 They are uniformly distributed and have perfect average. feeding the file to ent test suite yields low entropy value and ...
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1 vote
67 views

### Generating (pseudo) random numbers from a log file (eg. /var/log/maillog)

First: I really know that a true random number generator should have real random input, like something that is impossible to predict. Now, consider this: A busy mail-server can generate tens of ...
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### Can't load /root/.rnd into RNG : where can I find it, or how to create it?

I'm trying to setup a VPN server with OpenVPN, on an Ubuntu Server 18.04, and I want to use EasyRSA to build my PKI CA. So, while connected as root, I launch the EasyRSA scripts which I copied to /etc/...
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46 views

### Entering a random number sequence seed under surveillance [closed]

I'm trying to transmit a continuous sequence of random numbers from my computer over to another country (for validation purpose). This sequence is a series of pseudo random numbers recursively ...
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### dd is producing a 32 MB random file instead of 1 GB

I wanted to produce a 1 GB random file, so I used following command. dd if=/dev/urandom of=output bs=1G count=1 But instead every time I launch this command I get a 32 MB file: <11:58:40>\$ dd ...
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### Configure the default Random Number Generator algorithm in Windows.

How do I configure the default random number generator on Windows? Windows 7 and above. I would like to check whether the "Dual Elliptic Curve Deterministic Random Bit Generator (Dual EC DRBG)" ...
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1k views

### RANDBETWEEN but smaller than another cell value

I would like to generate a number that is random but smaller than the cell above (I'm doing 4th grade subtraction worksheet). What is the formula for this? I tried =randbetween(C3, 99) but it didn'...
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56 views

### Excel formula Help: Random sequence number

Would like to seek assistance for excel formula for difference between two or more numbers . In this sample if i put value randomly in cell G2 is there formula to put generate random number between ...
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44 views

### TrueRNG Pseudo GUI Issues - Collision

I am trying to create a Pseudo GUI for the TrueRNG Hardware using RNGCapture.exe and a custom Batch Based Menu. The RNGCapture program is only command line and a Royal Pain to create Multiple Entropy ...
477 views

### Play random movie/episode within a folder from its context menu

The Goal I have a relatively expansive media collection stored locally on my machine within two parent folders ("Movies" and "Shows"). My goal is to be able to play at random any one of the movies or ...
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### Auto generate unique number with no duplicate

How can I auto generate number if 1 of the column is fixed with the number that I want and another column randomly generate the number that is not in first column? I do not want any duplicate. For ...
366 views

### Unable to plot a scatter plot in excel

I have taken integers from 1 to 100 as my total population set. Now I generated 5 random numbers (using =randbetween() command) and called it my sample 1. Similarly, I created 200 such samples. Now I ...
1k views

### Biased Random results in Excel

Over on WorldBuilding we like to play with science-fictiony themes, including "what if there were more that two sexes" (examples here, here, here). All good clean fun and, I thought, a chance for me ...
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2k views

### How often does /dev/urandom sample seeding from /dev/random?

Unless I am totally confused and it doesn't do that. I want to know whether or not /dev/urandom will gain increased entropy if I take a hardware RNG and plug its entropy into /dev/random. So to ...
1 vote
449 views

### cat /dev/random brings up print dialog

I was just messing around and in the terminal of my Mac I did cat /dev/random just to watch the endless stream of random values. It has now brought up a print dialog and it wants to print half a page ...
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1k views

### What AMD processors provide RDRAND?

The latest AMD programmer manuals, dated June 2015, include the RDRAND instruction in the instruction set. Confer, AMD64 Architecture Programmer’s Manual Volume 3: General-Purpose and System ...
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### Should I use “/dev/random” or “/dev/urandom” for large random data needs? [duplicate]

Sometimes I want a lot of highly-random data, for example to overwrite a file or even a whole hard disk. Should I use /dev/random or /dev/urandom? What are the advantages or disadvantages of each? Is ...
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### Why am I constantly running out of entropy?

So I've been trying to create a new GPG key, and keep getting this well-known error: Not enough random bytes available. Please do some other work to give the OS a chance to collect more entropy! (...
1k views

### \/?' was unexpected at this time error in batch file

I am trying to integrate a password generator into my batch file so that it generates multiple passwords. Unfortunately it give the following error: \/?' was unexpected at this time. The expected ...
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537 views

### Random selection with a caveat / criteria

I have a 6 x 6 grid. I have 36 samples split into three equal groups (A, B, and C). I want a formula to arrange the samples in that grid randomly. However each row and each column must contain two of ...
1k views

### How do computers generate random numbers

This may very well be the only question I ever ask on this stackexchange site. In programming there are many different ways to generate random numbers depending on different languages. What has been ...
2k views

### How do I generate random numbers between a range in cells? [duplicate]

I'm wanting to create a button that generates a string of 10 random numbers into cells, and pulls the range for these random numbers from, for instance, in B1 and B2. Basically, I'm looking to use the ...
751 views

### Not quite grasping /dev/random and /dev/urandom

I am not quite understanding the difference between /dev/random and /dev/urandom on Linux systems. What does it mean to run out of “entropy” and how does the system get more? What does it mean when ...
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1k views

### How to generate inverted normal random numbers in VBA?

I am trying to generate 5.000 random variables using these excel functions: normsinv(rand()). This is the code I wrote: Dim r As Integer r = 1 For r = 1 To 5001 .Cells(r + 1, 1) = Application....
4k views

### Random Numbers in a Range of Cells

I want to generate random numbers in my model. Every time I run the macro my cells range "G8:H34" have to fill in with different random numbers that should be integers from 0 to 2. I have to ...
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1 vote
569 views

### How do computers generate random numbers? [closed]

How does a computer generate 'random' numbers? How close to truly 'random' can a number generated by a computer actually be? Is there software / programming language out that that might generate a ...
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### Creating a large file of random bytes quickly

I want to create a large file ~10G filled with zeros and random values. I have tried using: dd if=/dev/urandom of=10Gfile bs=5G count=10 it creates a file of about 2Gb and exits with a exit status 0....
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118k views

### How to keep random numbers from changing in Excel?

I am trying to generate a set list of random numbers between 1 and 5 using the RANDBETWEEN formula. I'm running into a problem that every time I click another cell anywhere in the sheet or even open ...
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81k views

### How are pseudorandom and truly random numbers different and why does it matter?

I've never quite got this. Just say you write a small program in any language at all which rolls some dice (just using dice as an example). After 600,000 rolls, each number would have been rolled ...
2k views

### Is reading from /proc/sys/kernel/random/entropy_avail draining entropy?

When I'm doing watch cat /proc/sys/kernel/random/entropy_avail, the amount of entropy steadily decreases, until I get about 150-200. Initially I get over 2000. When I stop reading that value and wait ...
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### Excel VBA: Rnd() method isn't random enough

I'm using Excel and VBA to simulate a large number of dice rolls. The problem I'm having is after a certain period of time, the rolls start repeating, and I start getting results that are anything ...
2k views

### Randomly reorder pages in PDF document

I'm looking for a series of commands to randomize the order of pages in an existing PDF document.
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### Why does `cat /dev/urandom` break your terminal?

In reference to this question: https://serverfault.com/questions/534449 How does cat /dev/urandom make some terminal emulators go wonky?
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### MS Excel: Unique random number generator within a range

I searched for a similar question but couldn't find one.. I want to generate 10 groups out of numbers ranging from 1-60 (including both), with each and every group containing random and non-repeating ...
1k views

### Calculating mean of value across random trials/refreshes in Excel?

Say I have a 1000 cells filled with random values and a particular cell that computes a final answer based on those 1000 values. Now I wish to track the value of the answer over 1000 trials i.e., I ...
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1k views

### What's the best way to get a random(ish) sequence of printable/alphanumeric characters?

I know I can get random (well, pseudo-random) characters, unconstrained, from '/dev/random' (or /dev/urandom). But what if I need these characters to generate a filename? I need to somehow have a ...
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### How can I know whether my machine have RNG hardware support?

I came across a blog concerning entropy pool problem and learn that there are a special hardware called RNG. I have read this kernel RNG page but I still wonder whether there is a way to find out if ...
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### Random Number in Linux

In linux /dev/random is based of "environmental variables" and /dev/urandom is based off an algorithm and the time. My questions are: Where does /dev/random gather these variables from. And if you ...
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### how to record mic input and pipe the output to another program

Hi everyone Im trying to follow a tutorial on generating truly random bits How To Generate Truly Random Bits This is the command from the tutorial but it does not work rec -c 1 -d /dev/dsp -r 8000 -...
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