Printable View
How do i write Time delay functions or instructions?
Like Delay for 40us or 80ms?
But how do i make them "overlap" if i had multiple time delays going on?
How do u modify or manipulate the random function?
Where can i get external random function librarys or librarys that have different random functions?
Each programming language has different random functions that are different ways of getting a random generator how do i call different programming language librarys please?
depends on the operating system. *nix call sleep(), MS-Windows Sleep() (note difference in capatilization), don't know about MAC or other operating systems. See man pages or msdn for parameters.Quote:
Originally Posted by markphaser
There can be only one delay at any given time for the same thread. Afterall, you can't delay a delay.Quote:
But how do i make them "overlap" if i had multiple time delays going on?
In C and C++ rand() will generate a random number, and srand() will set the seed. Call srand() only once during the lifetime of the program (shortly after start of main function).. C/C++ probably will not be able to call random function from libraries compiled and built with other languages.Quote:
How do u modify or manipulate the random function?
Where can i get external random function librarys or librarys that have different random functions?
Each programming language has different random functions that are different ways of getting a random generator how do i call different programming language librarys please?
Isn't it usleep()?Quote:
Originally Posted by Ancient Dragon
I think *nix has both functions, the difference is the parameters, one is seconds and the other milliseconds.Quote:
Originally Posted by OnionKnight
How do i set the "random seed" To get different random number sequences?
What sets the random number sequences like how to i change the "order" of the "number sequence"?
How do u change the current time at program's startup?
Why is the sequence is different at each startup?
How do u change the returns a random value in range?
easiest way to seed rand, i think another way is to use theCode:#include <time.h>
.
.
.
srand (time(0));
current process id but i havent ever used it so i cant comment.
remember to seed rand only once in your program.
EDIT:
Your other questions are a bit unclear, but to generate a random
number in a range 0 to x, call
to set the interval between two numbers x and y, where x isCode:number = rand ()/x+1;
the upper bound and y is lower, use
Code:number = rand ()/((x-y)+1) + y;
What is current process id?
set the interval between two numbers
The interval u mean in time interval?
""Each seed, defines a different number sequence"".
How many different seeds is there? how do u change the seed?
How do u modify or manipulate the "seed" please?
""Initializing the seed to the time, make the number sequence different for each program session."""
How do i initialize the seed to the time or to different times please?
how do i make a "Integer" Random function?
how do i call system libraries that have random functions
rand() returns a random integer already, from 0 - RAND_MAX. To simulate a random 'float', divide rand() / RAND_MAX. Do you want some other PRNG other than what the CRT provides or something?
your questions are extremely incoherent. the code i posted with
srand "seeds" the random function. it seeds it with the current
time, measured in seconds from the epoch. this epoch is different
on different systems, for example, on Unix it is the instant in time
when the very first Unix system became operational. this is some
date back in the 1970's, i dont know it by heart.
basically, this time (0) returns the number of seconds from this
epoch, and so it is a number that changes every second. this
is why we use it to seed rand, and as you have already pointed
out, each seed generates a unique set of random numbers.
think of it as being a parameter to a function that does some form
of calculation based on this parameter. it shouldn't be too hard to
accept that different parameters give different results.
with regards to process id, every program in memory has a unique
identy that the processor uses. these are integer values, and
since a processor operates so fast, it is acceptable to assume
from a human point of view that the current process id in use
is some "randomly" changing value (its not a random value, but
because of the fact that there are a huge range of values, that
change so rapidly, its a good seed).
now what i meant by interval has nothing to do with time, i
thought you wanted to generate an integer in a certain numerical
range, such as 0 to 10 or 5 to 20.
now i hope i've cleared some of that up for you, but i'm honestly
not sure i have. you're questions dont really make much sense,
(to me at least) so it is possible that i am misinterpretting them.
try to be more specific about what you want and you'll get more
specific answers. it appears that you seem to have some sort
of confusion about the connections between rand and time, so
i cant clarify this any more than i have.
a random 'float', divide rand() / RAND_MAX.
Do you want some other PRNG other than what the CRT provides or something?
Yes where do i find them or how do i make them up please?
I was thinking about calling other external librarys or system librarys from different programming languages like cobol, fortran,ect. because they have scientic and business random functions which C++ doesn't have or in the CRT
What is the theory behind random generators?
How can i make a random generator by scratch and manually
make one from ground up please?
The Random function is controlled by a Timing clock?
basic theory from my understanding, without using some sort of specialty hardware is to come up with an algorithim, that based on some seed generates some new psudeo-random number, with a very even distrobution between the minimum and maximum for output, using that output as the seed for the next run of the algorithum. Many algorithims rely on nothing but a seed which can come from any where, clock, pid, something non-constant is probably best so that its not something you can guess and get the exact same results every time.
Here is my question, why do you want to write one from scratch?
Thanks for the help
Where can u get different seeds?
or can u make up seeds from scratch?
The seed generates the psudeo random number?
Which clocks?
What is a "pid" please?
""something non-constant is probably best so that its not something you can guess and get the exact same results every time.""
Can u please give examples of something non constant for a random function to use?
Answer:Quote:
Where can u get different seeds?
or can u make up seeds from scratch?
>> The seed generates the psudeo random number?Quote:
a seed ... can come from any where, clock, pid, something non-constant is probably best so that its not something you can guess and get the exact same results every time.
The seed that you provide.
>> What is a "pid" please?
"Process ID"
>> Can u please give examples of something non constant for a random function to use?
Quote:
Code:srand (time(0));
Thanks for the help
How can a "seed" generate a psudeo random numbers?
How does random function generators work inside the code?
Is a Seed a special algorithm?
How can Random fucntion have more than one output? like 5 outputs before it returns or starts over?
Doesn't a random function have a pattern its going to repeat itself?
How can a totally logical machine like a computer generate a random number?
A seed is a 'random' starting point, like what time it is, from which the bits are flipped around to produce 'pseudo-random numbers'.
Wiki: Psuedo-random number generator
Thanks Tonto for the help
So the concepts is the random "Flips" and "shuffles" the bits around?
But how does it "Flip" and "shuffle" the bits ?
The random function "Distributes the bits around" but how does it do that?