Java Math.random() Method is a random number generating method that returns a double value between 0 and 1.
Java Math.random Method
Math.random() function has no parameters and output is always a random number between 0 and 1.
Example 1: Generate 1000 random numbers with Math.random() function and for loop. Find the minimum and maximum values among these random numbers.
double max=0; double min=1; for (int i=1; i<=1000; i++) { double rand = Math.random(); if (rand > max) max = rand; if (rand < min) min=rand; } System.out.println("Largest value: " + max); //0.9996603080869569 System.out.println("Smallest value: " + min); //0.0019330715654811703
Example 2: Generate a random number between 1 and 10 using Math.random() method
int num = (int)(Math.random() * 10) +1;
Example 3: Generate 20 random numbers between -5 and +5 (generating positive and negative numbers)
for (int i=1; i<=20; i++) { int num=(int)(Math.random()*11) - 5; System.out.print(num+" "); //-5 -1 3 1 0 -3 4 -2 2 1 -1 4 -3 -2 5 -4 -1 -5 4 5 }