random number in macro

[captsalmon]

I hope is is a quick and easy question. I tried to use rnd to generate a random number in a macro, but it just returns 0.522.... repeatedly.
I tried any number of variations on this, including rnd(), and even applications.worksheetfunction.rand(), but nothing.

so what am I doing wrong?

thanks in advance!

 

[rlv01]

Can you post your code to show how you using the rnd function?

 

[DanteAmor]

The Rnd function returns a value less than 1 but greater than or equal to zero.

The value of Number determines how Rnd generates a pseudo-random number:

• For any given initial seed, the same number sequence is generated because each successive call to the Rnd function uses the previous number as a seed for the next number in the sequence.
• Before calling Rnd, use the Randomize statement without an argument to initialize the random-number generator with a seed based on the system timer.

To produce random integers in a given range, use this formula:
Int ((upperbound - lowerbound + 1) * Rnd + lowerbound)


If you want to get an integer value you can use the following, for example between 1 and 10.

Sub test()
  Dim n As Long
 
  'for example between 1 to 10:
'sintax:
'Int ((upperbound - lowerbound + 1) * Rnd + lowerbound)
 
  Randomize
  n = Int((10 - 1 + 1) * Rnd + 1)
  MsgBox n
End Sub

 

[captsalmon]

Can you post your code to show how you using the rnd function?

I figured it out. it is returning a random number....but from the same seed variable, so the first one is always the same. this I did not know. I was just testing what I thought was simple code, and say 0.533 every time...so thought that it was not returning a random #. still seems crazy that everytime it will return the same series of 'random number'.

but thanks for your response...always good to know folks are willing to help out.

 

[captsalmon]

The Rnd function returns a value less than 1 but greater than or equal to zero.

The value of Number determines how Rnd generates a pseudo-random number:

• For any given initial seed, the same number sequence is generated because each successive call to the Rnd function uses the previous number as a seed for the next number in the sequence.
• Before calling Rnd, use the Randomize statement without an argument to initialize the random-number generator with a seed based on the system timer.

To produce random integers in a given range, use this formula:
Int ((upperbound - lowerbound + 1) * Rnd + lowerbound)


If you want to get an integer value you can use the following, for example between 1 and 10.

Sub test()
  Dim n As Long
 
  'for example between 1 to 10:
'sintax:
'Int ((upperbound - lowerbound + 1) * Rnd + lowerbound)
 
  Randomize
  n = Int((10 - 1 + 1) * Rnd + 1)
  MsgBox n
End Sub

thanks for the info. I figured out my original problem, and it was that I was just looking at a single output (the first run of a loop), and I was getting the same value, so thought it was not creating a random number. turns out it is...but from the same seed varible, and so always the same series of values. not very 'random' in my book. anyway I can introduce a new seed value with each run of the macro?

 

[MARK858]

anyway I can introduce a new seed value with each run of the macro?

From post number 3

Before calling Rnd, use the Randomize statement without an argument to initialize the random-number generator with a seed based on the system timer.

 

[DanteAmor]

anyway I can introduce a new seed value with each run of the macro?

Sure, in the variable n you will have a new random number in each execution:

Sub NewRandomNumber()
  Dim n As Double
  Randomize
  n = Rnd
  MsgBox n
End Sub