cosmetics

Doc/Sd1/appendix.xml

@@ -219,7 +219,7 @@
 
       <para>We start with the first task by implementing the <link
       xlink:href="https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes#Euler.27s_Sieve">Euler
-      sieve algorithm</link>. We may use a boolean array representing the
+      sieve algorithm</link>. We may use a boolean array representing e.g. the
       first 100 primes:</para>
 
       <programlisting language="java">boolean[] nonPrimes = new boolean[100];</programlisting>
@@ -237,9 +237,9 @@ value | t| t| f| f| t| f| t| f| t| t|  t|  f|  t|  f|  t ...</programlisting>
 
       <para>Since we intend to deal with a large number <code
       xlink:href="https://docs.oracle.com/javase/8/docs/api/java/lang/Integer.html#MAX_VALUE">Integer.MAX_VALUE</code>
-      of values we only consider odd values since even numbers are never prime
-      except for the value 2. Thus 0 will represent 1, 1 will represent 2 and
-      n will represent 2 * n + 1:</para>
+      of values (rather than just 100 ) we only consider odd values since even
+      numbers are never prime except for the value 2. Thus 0 will represent 1,
+      1 will represent 2 and n will represent 2 * n + 1:</para>
 
       <programlisting language="non">Index      | 0| 1| 2| 3| 4|  5|  6|  7| ...
 -----------+--+--+--+--+--+---+---+---+ ...
@@ -283,8 +283,11 @@ value      | f| f| f| f| t|  f|  f|  t| ...</programlisting>
       <tip>
         <para>Decompose the <link
         xlink:href="https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes#Euler.27s_Sieve">Euler
-        sieve algorithm</link> into smaller tasks and write appropriate
-        tests.</para>
+        sieve algorithm</link> into smaller tasks and write appropriate tests.
+        Start with small <code>limit</code> values (like 20) and extend to
+        <code
+        xlink:href="https://docs.oracle.com/javase/8/docs/api/java/lang/Integer.html#MAX_VALUE">Integer.MAX_VALUE</code>
+        step by step.</para>
       </tip>
 
       <para>Once you've finished implementing the sieve continue by
@@ -358,7 +361,7 @@ public class PrimeFrequencySet {
 
    private final static int initialCapacity = 16;
    
-   private PrimeFrequency[] store = new PrimeFrequency[initialCapacity];
+   private PrimeFrequency[] store = new PrimeFrequency[initialCapacity]; // May grow due to new factors.
 
    /**
     * Searching for the existence of a {@link PrimeFrequency} with a matching
@@ -423,7 +426,16 @@ public class PrimeFrequencySet {
       <para>This allows for decomposing arbitrary <code>int</code> values into
       their prime factors. We show a unit test example:</para>
 
-      <programlisting language="java">      PrimeFrequencySet pfs = sieve.getPrimeFactors(12); <co
+      <programlisting language="java">/**
+ * Prime factor decomposition.
+ */
+public class FactorTest {
+
+   final Sieve sieve = new Sieve(100000);
+
+   @Test
+   public void test2 () {
+      PrimeFrequencySet pfs = sieve.getPrimeFactors(12); <co
           linkends="sd1ListingTestPrimeFactorDecompose-1"
           xml:id="sd1ListingTestPrimeFactorDecompose-1-co"/>
       Assert.assertEquals(2, pfs.getLength()); <co
@@ -434,7 +446,9 @@ public class PrimeFrequencySet {
           xml:id="sd1ListingTestPrimeFactorDecompose-3-co"/>
       Assert.assertEquals(new PrimeFrequency(3, 1), pfs.get(1)); <co
           linkends="sd1ListingTestPrimeFactorDecompose-4"
-          xml:id="sd1ListingTestPrimeFactorDecompose-4-co"/></programlisting>
+          xml:id="sd1ListingTestPrimeFactorDecompose-4-co"/>
+   }
+}</programlisting>
 
       <calloutlist>
         <callout arearefs="sd1ListingTestPrimeFactorDecompose-1-co"