A Loop with an Integer Variable

Classic programmed-learning exercises, refreshed for modern Java and presented in the current MrStyner.com portfolio style.

Modern Java noteThis archive has been refreshed for Java 25 LTS. Core language concepts remain useful, while outdated setup instructions and browser-era Java are labeled or replaced. Java 26 is the current feature release; Java 25 is used here as the stable teaching baseline.
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Answer:

Yes. 1 + 1 is always exactly 2, with integers. (But you do need to worry about overflow when the operands get too big.)

A Loop with an Integer Variable

Often a program uses an integer loop control variable which is used to compute a floating point x for every iteration of the loop:

class LogTable
{
  public static void main ( String[] args )
  {
    System.out.println( "x" + "/t ln(x)" );

    for ( int j = 1; j <= 20; j++ )
    {
      double x = j/10.0 ;
      System.out.println( x + "/t" + Math.log( x ) );
    }
  } 
}

This is not without problems, but at least the errors in x are not accumulating. Here is the output:

x        ln(x)
0.1     -2.3025850929940455
0.2     -1.6094379124341003
0.3     -1.2039728043259361
0.4     -0.916290731874155
0.5     -0.6931471805599453
0.6     -0.5108256237659907
0.7     -0.35667494393873245
0.8     -0.2231435513142097
0.9     -0.10536051565782628
1.0     0.0
1.1     0.09531017980432493
1.2     0.1823215567939546
1.3     0.26236426446749106
1.4     0.33647223662121284
1.5     0.4054651081081644
1.6     0.4700036292457356
1.7     0.5306282510621704
1.8     0.5877866649021191
1.9     0.6418538861723947
2.0     0.6931471805599453

The result of dividing  j by 10.0 is not completely accuracy. However, dividing an integer by a power of two, is accurate (as long as the result is not too small).

QUESTION 7:

Is 8 a power of two?