11-04-2015
@Jim, /dev/random gives the better random numbers but is slower than /dev/urandom!
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1. Shell Programming and Scripting
Hello, need a way to generate numbers within 0.5-1.5 range
Has to be totally random:
0.6
1.1
0.8
1.5
0.6
and so on....
How to? (10 Replies)
Discussion started by: TehOne
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2. Shell Programming and Scripting
Hi,
I am having trouble with generating random numbers. can this be done with awk?
So I have a file that looks like this:
23 30
24 40
26 34
So column1 is start and column2 is end. I want to generate 3 random #'s between start and stop:
So the output will look like this:
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3. Programming
Hi,
How can we generate 16 digit random nos in C. (10 Replies)
Discussion started by: ajaysahoo
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4. Programming
Im new to C, and Im having a hard time getting a random number.
In bash, I would do something similar to the following to get a random number;
#!/bin/bash
seed1=$RANDOM
seed2=$RANDOM
seed3=$RANDOM
SEED=`expr $seed1 * $seed2 / $seed3`
echo ${SEED%.*}
Now, in online examples... (4 Replies)
Discussion started by: trey85stang
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5. Shell Programming and Scripting
I want to generate an awk function that generated a Gaussian distributed set of random numbers. I need to implement the thing below in awk. Rnd is just a uniform random number between 0 and 1
function rgaussian(r1, r2) {
Do
v1 = 2 * Rnd - 1
v2 = 2 * Rnd - 1
... (0 Replies)
Discussion started by: kristinu
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6. Shell Programming and Scripting
Hi,
I hope someone can share there scripting fu on my problem,
I would like to delete the 3rd character from a random length of string starting from the end
Example
Output
Hope you can help me..
Thanks in advance.. (3 Replies)
Discussion started by: jao_madn
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7. UNIX for Dummies Questions & Answers
Hello.
Could anyone help me with my little annoying problem?
I have to generate a 512 MB file made up with random data using DD. After some internet digging I found out that the command is:
dd if=/dev/urandom of=/exemple/file bs=512MB
After running this command the... (2 Replies)
Discussion started by: razolo13
2 Replies
8. Shell Programming and Scripting
Hi there I am trying to generate a random number between 40 and 70 using the shell here is my code so far and it keeps going above 70. all help much appreciated!
comp=$(( RANDOM%70+40 ))
echo $comp (4 Replies)
Discussion started by: faintingquiche
4 Replies
9. Shell Programming and Scripting
Having a hard time with this. Very new to scripting and linux. Spent all sunday trying to do this. Appreciate some help and maybe help breaking down what the syntax does.
Create a Bash program. It should have the following properties
• Creates a secret number between 1 and 100
i. The... (3 Replies)
Discussion started by: LINUXnoob15
3 Replies
10. Shell Programming and Scripting
Hi Guys and gals...
As you know I am getting to grips with POSIX and hit this stumbling block.
Generating two random numbers 0 to 255 POSIXly. Speed in not important hence the 'sleep 1' command.
I have done a demo that works, but it sure is ugly! Is there a better way?
#!/bin/sh
# Random... (12 Replies)
Discussion started by: wisecracker
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LEARN ABOUT MOJAVE
random
RANDOM(4) BSD Kernel Interfaces Manual RANDOM(4)
NAME
random , urandom -- random data source devices.
SYNOPSIS
pseudo-device random
DESCRIPTION
The random device produces uniformly distributed random byte values of potentially high quality.
To obtain random bytes, open /dev/random for reading and read from it.
The same random data is also available from getentropy(2). Using the getentropy(2) system call interface will provide resiliency to file
descriptor exhaustion, chroot, or sandboxing which can make /dev/random unavailable. Additionally, the arc4random(3) API provides a fast
userspace random number generator built on the random data source and is preferred over directly accessing the system's random device.
/dev/urandom is a compatibility nod to Linux. On Linux, /dev/urandom will produce lower quality output if the entropy pool drains, while
/dev/random will prefer to block and wait for additional entropy to be collected. With Yarrow, this choice and distinction is not necessary,
and the two devices behave identically. You may use either.
The random device implements the Yarrow pseudo random number generator algorithm and maintains its entropy pool. The kernel automatically
seeds the algorithm with additional entropy during normal execution.
FILES
/dev/random
/dev/urandom
HISTORY
A random device appeared in the Linux operating system.
Darwin September 6, 2001 Darwin