Random numbers

George Krietsepis · June 2020

Dear All,

I need to randomly select 10 numbers from 1-100 and store them in an array. Random_number(101) selects a number in range 0 <= number < 101 but zero must be excluded.

I could make some piece of code to check if the selected number is zero:

for (iNumber= 1 ; iNumber <=10 ; iNumber ++)
{
iNumberArray[iNumber] = random_number(101);

    while ( iNumberArray[iNumber] == 0 )    
            iNumberArray[iNumber] = random_number(101);   
}

I need then to check these 10 numbers to be different for each other. If there are equal numbers, it should re select different ones
Finally I need to short them from the lower to the higher number

Basically, I’d like to ask some help for 2 and 3.

Thanks,
George

richardherman · June 2020

You could do something like this. I have checked this quickly and it works as expected, but depending on how 'paranoid' you are, it could be worth checking this more thorough.

DEFINE_CONSTANT

MAX_NUMBERS = 10

DEFINE_VARIABLE

volatile long lNumberArray[MAX_NUMBERS]
volatile long lSortedArray[MAX_NUMBERS]

Functions:

1 - generate the array

define_function fnFillArray()
{
    stack_var volatile integer i

    for (i = 1 ;i <= MAX_NUMBERS ;i ++)
    {
    //set max range 1 lower and add 1 to avoid zero
    lNumberArray[i] = random_number(100) + 1
    set_length_array(lNumberArray, MAX_NUMBERS)
    }   
}

You can check the array with debug. You can change some array members to be duplicates of others there also, to check the next function.

2 - check for duplicates

define_function fnFindDuplicates(long lArray[])
{
    stack_var volatile integer i
    stack_var volatile integer j
    stack_var volatile integer nDuplicate

    while (TRUE)
    {
    //after replacing a duplicate check again
    //cause it could be another duplicate
    for (i = 1; i <= length_array(lArray); i++)
    {
        for (j = i + 1; j <= length_array(lArray); j++) 
        {
        if (lArray[i] == lArray[j]) 
        {
            send_string 0,"'Duplicate: ',itoa(lArray[i])"
            //re-generate and check array again
            lNumberArray[i] = random_number(100) + 1
            nDuplicate = i
            break
        }
        else
            nDuplicate = FALSE
        }
        if (nDuplicate)
        break
    }
    if (!nDuplicate)
    {
        send_string 0,'Duplicate checking done!'
        return
    }
    }
}

3 - Sort the array

This is a 'standard' insertion sort routine. If you want to know how it works, just Google. Lots of examples.

define_function long[MAX_NUMBERS] fnSortArray(long lArray[])
{
    //insertion sort routine

    stack_var volatile integer i
    stack_var volatile long    lValueToInsert
    stack_var volatile integer nHoleposition
    stack_var volatile long    lTempArray[MAX_NUMBERS]

    lTempArray = lArray

    for (i = 2; i <= length_array(lTempArray); i++) 
    {
    lValueToInsert = lTempArray[i]
    nHoleposition = i
    while (lValueToInsert < lTempArray[nHoleposition - 1]) 
    {
        lTempArray[nHoleposition] = lTempArray[nHoleposition - 1]
        nHoleposition --
        if (nHoleposition == 1) 
        {
        break
        }
    }
    lTempArray[nHoleposition] = lValueToInsert
    }
    send_string 0,'Sorting done!'
    return lTempArray
}

I tested these functions with simple triggers from pulsing channels on a virtual device with 'control a device' and checking the results in 'debug' but there are may ways of doing this.

DEFINE_DEVICE

vdvStart = 33000:1:0

DEFINE_EVENT

channel_event [vdvStart,1]
{
    ON:
    {
    fnFillArray()
    }
}

channel_event [vdvStart,2]
{
    ON:
    {
    fnFindDuplicates(lNumberArray)
    }
}

channel_event [vdvStart,3]
{
    ON:
    {
    lSortedArray = fnSortArray(lNumberArray)
    }
}

Good luck

George Krietsepis · June 2020

hello richardherman,

 they are all so useful..... I will give a try.... Many thanks for your help and your time !!!

George

Random numbers

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