473,322 Members | 1,431 Online
Bytes | Software Development & Data Engineering Community
Post Job

Home Posts Topics Members FAQ

Join Bytes to post your question to a community of 473,322 software developers and data experts.

Generating random number using C++

hi,

i need help with generating random numbers;

The task is to generate hundreds of random vectors, like
1,3,5,6,7
2,4,5,4,8
...

I used the current time as the random seed, but it turns out
that every vector to be the same. I guess the problem arise
because the precision of time function limits to 1 second,
and in a very short time interval, the random seed is exactly
the same and thus all the vectors the same.

Does anybody know some better seed for this problem? or
any other random number generating functions?

Thanks,
Z
Oct 30 '06 #1
2 2706
Ganon11
3,652 Expert 2GB
Are you calling the randomize function (a.k.a. resetting the seed) more than once? I once got a similar problem, getting the same 'random' numbers over and over again, because I reset the seed multiple times. Try setting the seed once in the very beginning of your main.
Oct 30 '06 #2
Thanks, it works.
Oct 31 '06 #3

Sign in to post your reply or Sign up for a free account.

Similar topics

7
by: eric.gagnon | last post by:
In a program randomly generating 10 000 000 alphanumeric codes of 16 characters in length (Ex.: "ZAZAZAZAZAZAZ156"), what would be an efficient way to ensure that I do not generate duplicates? ...
16
by: Leon | last post by:
I need a program that generate 5 non-duplicates random number between 1-10 as string values store in an array. Do anybody know of any good books or websites that explain how to generator random...
6
by: Intiha | last post by:
Hello all, I am trying to generate random seeds for my simulations. currently i was using srand(time(NULL); for this purpose. But for confidence in my results i ran it using a script in a loop....
2
by: Simon Wittber | last post by:
I'm building a web application using sqlalchemy in my db layer. Some of the tables require single integer primary keys which might be exposed in some parts of the web interface. If users can...
1
by: Velhari | last post by:
Hi, I am a beginner. Please tell me, For generating Random Numbers, Initially why we are going for seed method. And another question is that, I want to print unique random number how to print by...
14
by: avanti | last post by:
Hi, I need to generate random alphanumeric password strings for the users in my application using Javascript. Are there any links that will have pointers on the same? Thanks, Avanti
5
by: dav3 | last post by:
Howdy folks, was wondering if anyone could assist me in a better method for generating a alphanumeric sequence of 6 characters/digits. The method I am currently using gives me a random license plate...
0
SammyB
by: SammyB | last post by:
These are some "random" thoughts about generating random numbers in Visual Basic. Wikipedia will give a better introduction than I, see http://en.wikipedia.org/wiki/Random_number_generator. ...
26
by: bilgekhan | last post by:
What is the correct method for generating 2 independent random numbers? They will be compared whether they are equal. What about this method: srand(time(0)); int r1 = rand(); srand(rand());...
0
by: ryjfgjl | last post by:
ExcelToDatabase: batch import excel into database automatically...
0
isladogs
by: isladogs | last post by:
The next Access Europe meeting will be on Wednesday 6 Mar 2024 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM). In this month's session, we are pleased to welcome back...
1
isladogs
by: isladogs | last post by:
The next Access Europe meeting will be on Wednesday 6 Mar 2024 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM). In this month's session, we are pleased to welcome back...
0
by: ArrayDB | last post by:
The error message I've encountered is; ERROR:root:Error generating model response: exception: access violation writing 0x0000000000005140, which seems to be indicative of an access violation...
1
by: PapaRatzi | last post by:
Hello, I am teaching myself MS Access forms design and Visual Basic. I've created a table to capture a list of Top 30 singles and forms to capture new entries. The final step is a form (unbound)...
1
by: CloudSolutions | last post by:
Introduction: For many beginners and individual users, requiring a credit card and email registration may pose a barrier when starting to use cloud servers. However, some cloud server providers now...
1
by: Shællîpôpï 09 | last post by:
If u are using a keypad phone, how do u turn on JavaScript, to access features like WhatsApp, Facebook, Instagram....
0
by: af34tf | last post by:
Hi Guys, I have a domain whose name is BytesLimited.com, and I want to sell it. Does anyone know about platforms that allow me to list my domain in auction for free. Thank you
0
isladogs
by: isladogs | last post by:
The next Access Europe User Group meeting will be on Wednesday 3 Apr 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM). In this session, we are pleased to welcome former...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.