A set of random numbers. Random number generator online

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Numbers accompany us everywhere - house and apartment numbers, telephone numbers, car numbers, passport numbers, plastic cards, dates, passwords. Email. We choose some combinations of numbers ourselves, but most we get by chance. Without realizing it, we use randomly generated numbers every day. If we come up with PIN codes, then unique credit or salary card are generated by reliable systems that exclude access to passwords. Generators random numbers provide protection in areas requiring speed of information processing, security and independent processing of data.

The process of generating pseudorandom numbers is subject to certain laws and has been used for a long time, for example, in lotteries. In the recent past, drawings were carried out using lottery machines or lots. Now in many countries, the winning numbers of state lotteries are determined precisely by a set of generated random numbers.

Advantages of the method

So, a random number generator is an independent modern mechanism for randomly determining combinations of numbers. The uniqueness and perfection of this method lies in the impossibility of external intervention in the process. The generator is a set of programs built, for example, on noise diodes. The device generates a stream of random noise, the current values of which are converted into numbers and form combinations.

Generating numbers provides instant results - it takes a few seconds to create a combination. If we talk about lotteries, participants can immediately find out whether the ticket number matches the winning one. This allows drawings to be held as often as participants want. But the main advantage of the method is its unpredictability and the impossibility of calculating the algorithm for selecting numbers.

How pseudorandom numbers are generated

In fact, random numbers are not random - the series starts from a given number and is generated by an algorithm. A pseudorandom number generator (PRNG or PRNG - pseudorandom number generator) is an algorithm that generates a sequence of seemingly unrelated numbers, usually subject to a uniform distribution. In computer science pseudorandom numbers used in many applications: cryptography, simulation modeling, Monte Carlo method, etc. The quality of the result depends on the properties of the PRNG.

The source of generation can be physical noise from cosmic radiation to noise in a resistor, but such devices are almost never used in network security applications. Cryptographic applications use special algorithms that generate sequences that cannot be statistically random. However, a properly chosen algorithm can produce series of numbers that pass most randomness tests. The repetition period in such sequences is greater than the working interval from which the numbers are taken.

In many modern processors contains PRNG, for example, in RdRand. As an alternative, sets of random numbers are created and published in a one-time pad (dictionary). The source of numbers in this case is limited and does not provide complete network security.

History of PRNG

A prototype of a random number generator can be considered board game Senet, common in Ancient Egypt in 3500 BC. According to the conditions, two players participated, the moves were determined by throwing four flat black and white sticks - they were a kind of PRNG of that time. The sticks were thrown at the same time, and points were counted: if one fell up with the white side, 1 point and an additional move, two white ones - two points, and so on. Maximum result The player who threw out four sticks with the black side received five points.

Nowadays, the ERNIE generator has been used for many years in the UK for lottery draws. There are two main methods for generating winning numbers: linear congruent and additive congruent. These and other methods are based on the principle of random selection and are provided by software that endlessly produces numbers whose sequence is impossible to guess.

The PRNG operates continuously, for example, in slot machines. According to US law, this required condition, which all software providers must comply with.

Greetings, dear readers! In this article I want to talk to you about the popular site random.org, with which you can choose a random winner in any competition. It doesn’t matter for which platform you choose the winner of the competition: Vkontakte, Twitter, Facebook, blog or website - the most important thing is that you have a ready list of participants, since random.org is just a random number generator and it is not capable of selecting participants according to a given criterion.

We choose a winner on Facebook

I don’t like long stories, so I’ll get straight to the point :)) If you want to determine the winner of a competition held on a Facebook page, then everything is very simple. There are some great sites that will allow you to easily and easily export all the likes and comments from any post you choose in CSV format. You can then run these lists through the random.org number generator and thus choose a random winner.

Note: Since reposts, as a condition of participation in competitions on Facebook, are strictly prohibited by the rules, there are no services that will automatically calculate them for you. In general, I do not advise breaking the rules on Facebook, since a lifelong ban on a page is a rather expensive price that, God forbid, you will have to pay for such violations.

We choose a winner on VKontakte

Over time, I have compiled a fairly voluminous list of applications and websites that can be used to determine the winner among social users. VKontakte network. For convenience, I have moved the list to a separate article.

How to choose a random winner using random.org

We've sorted out the lists of participants, so let's return to the topic of random.org. There are two types of services on the site: paid and free. The difference is that if you choose a winner paid method, then random.org stores all the results, creating a kind of official sampling protocol. See. If your audience trusts you 100% and there is no need to prove that the draw was carried out properly, then you can safely use free service and simply show all participants a screenshot with the results of the draw. If there is a need for official confirmation of the sampling, then below I will tell you how to choose a winner using a paid method.

Free sample

So, if your audience trusts you, then there is no need to pay for sampling. In this video you will learn how to choose a random winner in two free ways:

Using a random number generator;
Using a list randomizer.

Paid sampling

If you're running a competition with a large number of entrants or large prizes, you'll likely be more interested in an official draw that retains the results of the draw.

Prices

The sampling price on random.org depends on the number of participants. If you have no more than 500 people on your list, then such a sample will cost you very little - $4.95. 1000 participants will cost a little more - $8.95. I will not list all the prices here, especially since they are on the website. Random.org's price per sample with a small number of participants is slightly lower than its competitors, such as Random Picker. But if you have more than 3,000 participants, then I advise you to use the site, since it has a fixed price per project - $25 (than more projects, the cheaper). In addition, the site has been translated into Russian, which is undoubtedly a big plus.

If with English language If you have no problems and you can register on the site without any problems, then just skip this section. I've received a lot of questions about registering on random.org, so I'll tell you how to do it.

Step 1. Click on Login in the right top corner and in the window that opens, click on register.

Step 2. Enter the registration information, as shown in the figure below. Please note that the name you put in the second paragraph will be indicated in the sampling protocol, so choose either your name or the name of your company, page or site. Click on the Proceed button.

Step 3. Next, you need to choose how much you will pay for the sample. If you have less than 500 participants, then select the second line with a price of $4.95 - this is minimum amount for registration. That is, if you just want to register on the site without paying (1st line), you won’t succeed. I don't know why they even made this option.

Next, if you have about 5,000 participants or want to hold several lotteries with fewer participants, then choose the third line with a price of $34.95. The same goes for the fourth line - $249.95 for 100,000 participants or n number of small samples.

The most effective options offered by random.org are the second one with $4.95 or the last one, where you choose how much money you want to deposit. Don't forget to use the price calculator, the link to which I provided above.

Step 4. This step is not at all interesting to us. random.org asks if you want to subscribe to additional service"Customizable random number generator." You won't need it to hold competitions, so choose the first line.

Step 5. Well last step— account confirmation. Please pay Special attention that you have entered the correct email. address, since you will be sent a password to log into your account.

If payment information and email address. emails are entered correctly, then check the box to confirm that you agree with everything and click on the Pay with PayPal button. You will be redirected to the PayPal page to pay. As soon as the money arrives in your random.org account, your account will be created.

That's all! Registration is complete!

Official winner's selection at random.org

In this section, we will take a closer look at how to determine the winner on random.org. For example, I will use screenshots from random.org.

Step 1. Sign in to your account.

Step 2. A window will open, as in the figure, with information about all previous samples (if there were any, of course). Click on the “pick a new winner” button.

Step 3. In a new window, enter the name of the competition or a brief description of it.

The results will be visible only to competition participants: In order to check whether a participant was included in the list, he will need to enter an identifier, that is, the information that you used in the lists, for example, names, email addresses. mail, UID and so on. The participant will only be able to see general information about the draw: name, total number of participants, but will not be able to see the entire list. .
Closed selection: the sample results and list of participants are available only to you.
Open selection: the sample results and list of participants will be visible to anyone who follows the protocol link. .
Test sample.

Step 4. Next, choose the method for entering the list of participants. Everything seems to be clear here. I will only note that if you choose a method for downloading a file, then the list should be in text format txt. For both methods, each individual participant must be entered on a separate line, that is, no listing separated by commas or separated by spaces.

If you are very a large number of participants, the file may take longer to download and process.

Step 5. You don't need to do anything in this step, as random.org will do everything itself. The point of this step is to check your list for duplicates and empty fields. If the fields highlighted in the figure yellow- green, then I didn’t find any problems with the random.org list. If your list contains duplicates or empty fields, you will have to go back, correct those issues, and re-upload the list of participants. If you are okay with the list, then move on by clicking on Proceed.

Step 7 Next we move on to the sample confirmation step. Be very careful that all information is entered correctly, since at this stage there is still a chance to go back and correct something. If you click on the Complete the drawing button, money will be debited from your account.

Step 8 The list of winners is ready! If you have defined open type samples, i.e. made the results available to the general public or participants, then on this page you will have a link that you can publish at the competition location. There is no need to save this link as you can find it in your account dashboard.

Well, that seems to be all, friends, that I wanted to tell and show you about random.org. I really hope that you found the information you were looking for. I would be grateful if you share my article with everyone who may find this information useful and interesting.

If you have not yet subscribed to blog updates, you can do so using this link. Don't forget to also follow latest news in social networks.

With this generator you can create random numbers in any range. This generator will also allow you to randomly select or determine a number from a list. Or create an array of random numbers from 2 to 70 elements. This online tool will not only allow you to create one (1), two (2) or three digit (3) random numbers, but also five and seven. Easy to set up. Everyone can master it. You will also be able to select random numbers for online or offline lotteries or contests. And it will be convenient. You can easily create entire tables or series of random numbers. In a split second you will receive a random number or a sequence of them (set) on your screen. If you take a sequence of your numbers, then the algorithm will choose a random one or random ones, any one can fall out. You yourself can use this tool to conduct sweepstakes. By choosing, for example, the same range and number of numbers in the result, you can generate random sequence(combination). You can also choose random letter combinations and words. This tool, like everything on our site, is completely free to use (no exceptions).

Enter range numbers

From
Before
Generate

Changing the range to generate a random number

1..10 1..100 1..1000 1..10000 for lottery 5 out of 36 for lottery 6 out of 45 for lottery 6 out of 49 for lottery 6 out of 59

Number of random numbers (1)

Eliminate repetitions

Select random values from the list (separate by commas or spaces, if commas are found, division will be done by them, otherwise by spaces)

We have a sequence of numbers consisting of practically independent elements that obey a given distribution. As a rule, uniform distribution.

You can generate random numbers in Excel in different ways and methods. Let's consider only the best of them.

Random Number Function in Excel

The RAND function returns a uniformly distributed random real number. It will be less than 1, greater than or equal to 0.
The RANDBETWEEN function returns a random integer.

Let's look at their use with examples.

Sampling random numbers using RAND

This function requires no arguments (RAND()).

To generate a random real number in the range from 1 to 5, for example, use the following formula: =RAND()*(5-1)+1.

The returned random number is distributed uniformly over the interval.

Each time the worksheet is calculated or the value in any cell in the worksheet changes, a new random number is returned. If you want to save the generated population, you can replace the formula with its value.

Click on the cell with a random number.
In the formula bar, select the formula.
Press F9. AND ENTER.

Let's check the uniformity of the distribution of random numbers from the first sample using a distribution histogram.

The range of vertical values is frequency. Horizontal - “pockets”.

RANDBETWEEN function

The syntax for the RANDBETWEEN function is (lower bound; upper bound). The first argument must be less than the second. Otherwise the function will throw an error. The boundaries are assumed to be integers. Fractional part the formula is discarded.

Example of using the function:

Random numbers with precision 0.1 and 0.01:

How to make a random number generator in Excel

Let's make a random number generator that generates a value from certain range. We use a formula like: =INDEX(A1:A10,INTEGER(RAND()*10)+1).

Let's make a random number generator in the range from 0 to 100 in steps of 10.

From the list text values you need to choose 2 random ones. Using the RAND function, we compare text values in the range A1:A7 with random numbers.

Let's use the INDEX function to select two random text values from the original list.

To select one random value from the list, use the following formula: =INDEX(A1:A7,RANDBETWEEN(1,COUNT(A1:A7))).

Normal distribution random number generator

The RAND and RANDBETWEEN functions produce random numbers with a uniform distribution. Any value with the same probability can fall into the lower limit of the requested range and into the upper one. This results in a huge spread from the target value.

A normal distribution implies that most of the generated numbers are close to the target number. Let's adjust the RANDBETWEEN formula and create a data array with a normal distribution.

The cost of product X is 100 rubles. The entire batch produced follows a normal distribution. A random variable also follows a normal probability distribution.

Under such conditions, the average value of the range is 100 rubles. Let's generate an array and build a graph with a normal distribution with a standard deviation of 1.5 rubles.

We use the function: =NORMINV(RAND();100;1.5).

Excel calculated which values were within the probability range. Since the probability of producing a product with a cost of 100 rubles is maximum, the formula shows values close to 100 more often than others.

Let's move on to plotting the graph. First you need to create a table with categories. To do this, we divide the array into periods:

Based on the data obtained, we can generate a diagram with a normal distribution. The value axis is the number of variables in the interval, the category axis is periods.

Anyone who tries to generate random numbers using arithmetic methods is, of course, living in sin.
- John von Neumann

Sequence Generator

Generates a sequence with all unique integers in a given range. Essentially what Collections.shuffle() does. For example, this is what a request to shuffle a deck of cards looks like:
http://www.random.org/sequences/?min=1&max=52&col=1&format=plain&rnd=new

String Generator

Generates a random string of a given size with the ability to select a set of characters (numbers, lower case, upper case). This is how, for example, you can generate a nickname for your character and a password:
http://www.random.org/strings/?num=1&len=12&digits=on&upperalpha=on&loweralpha=on&unique=on&format=plain&rnd=new

Quota Checker

Well, as you already understand, all this is not free. Although no, they give a million free bits per day. This is more than enough. And in order to find out how much is left, you can use the following link:
http://www.random.org/quota/?format=plain
If you clicked on the three previous links, then you have already spent ~1500 bits.

Errors

If the generation is successful, the server returns code 200, failure - code 503. That's all the errors.

A library was written for this API from five classes in Java, in which all the methods described above are called in a simple and understandable form.
// roll the dice IntegerGenerator ig = new IntegerGenerator(); ig.generate(1, 6, 2); // shuffle the cards SequenceGenerator sg = new SequenceGenerator(); sg.generate(1, 52); // new password StringGenerator strg = new StringGenerator(); strg.generate(12, 1, true, true, true, true); // how many bits are left QuotaChecker qc = new QuotaChecker(); qc.quota();

That seems to be all. On github you can download the source code and the lib with the original name randomorg(6 kilobytes).