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Full Discussion: Generating random numbers
Top Forums Shell Programming and Scripting Generating random numbers Post 302341516 by kshji on Thursday 6th of August 2009 05:23:53 AM
Old 08-06-2009
Code:
#!/bin/ksh
# or bash
cat file | while read a b
do
        echo -n "$a $b"
        ((max=b-a))
        ((n=RANDOM % max + a))
        echo -n " $n"
        ((n=RANDOM % max + a))
        echo -n " $n"
        ((n=RANDOM % max + a))
        echo " $n"
done

You can use shell services also in awk like - not so good as use rand. Shell using = lot of overheading:
Code:
     # define cmd
     cmd="echo $RANDOM"
     cmd | getline  random
     # close pipe
     close(cmd)

 

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MAX(3)									 1								    MAX(3)

max - Find highest value

SYNOPSIS
mixed max (array $values) DESCRIPTION
mixed max (mixed $value1, mixed $value2, [mixed $...]) If the first and only parameter is an array, max(3) returns the highest value in that array. If at least two parameters are provided, max(3) returns the biggest of these values. Note Values of different types will be compared using the standard comparison rules. For instance, a non-numeric string will be com- pared to an integer as though it were 0, but multiple string values will be compared alphanumerically. The actual value returned will be of the original type with no conversion applied. PARAMETERS
o $values - An array containing the values. o $value1 - Any comparable value. o $value2 - Any comparable value. o $... - Any comparable value. RETURN VALUES
max(3) returns the parameter value considered "highest" according to standard comparisons. If multiple values of different types evaluate as equal (e.g. 0 and 'abc') the first provided to the function will be returned. EXAMPLES
Example #1 Example uses of max(3) <?php echo max(2, 3, 1, 6, 7); // 7 echo max(array(2, 4, 5)); // 5 // The string 'hello' when compared to an int is treated as 0 // Since the two values are equal, the order they are provided determines the result echo max(0, 'hello'); // 0 echo max('hello', 0); // hello // Here we are comparing -1 < 0, so 'hello' is the highest value echo max('hello', -1); // hello // With multiple arrays of different lengths, max returns the longest $val = max(array(2, 2, 2), array(1, 1, 1, 1)); // array(1, 1, 1, 1) // Multiple arrays of the same length are compared from left to right // so in our example: 2 == 2, but 5 > 4 $val = max(array(2, 4, 8), array(2, 5, 1)); // array(2, 5, 1) // If both an array and non-array are given, the array will be returned // as comparisons treat arrays as greater than any other value $val = max('string', array(2, 5, 7), 42); // array(2, 5, 7) // If one argument is NULL or a boolean, it will be compared against // other values using the rule FALSE < TRUE regardless of the other types involved // In the below example, -10 is treated as TRUE in the comparison $val = max(-10, FALSE); // -10 // 0, on the other hand, is treated as FALSE, so is "lower than" TRUE $val = max(0, TRUE); // TRUE ?> SEE ALSO
min(3), count(3). PHP Documentation Group MAX(3)
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