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author | Iulian Dragos <jaguarul@gmail.com> | 2010-04-13 22:51:04 +0000 |
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committer | Iulian Dragos <jaguarul@gmail.com> | 2010-04-13 22:51:04 +0000 |
commit | d95eb2a8f979b9f9db98a0e097ef3793674e57ab (patch) | |
tree | 6e11ba6e02cdd30c53861d42e6e52d5ce34b8d95 /test/files/run/Course-2002-10.scala | |
parent | c272bbfb64b1d0522e09daa0981a4942f63607a4 (diff) | |
download | scala-d95eb2a8f979b9f9db98a0e097ef3793674e57ab.tar.gz scala-d95eb2a8f979b9f9db98a0e097ef3793674e57ab.tar.bz2 scala-d95eb2a8f979b9f9db98a0e097ef3793674e57ab.zip |
Made the icode reader more resilient to errors.
symbol does not cause any crashes, but the method using an unknown
symbol will not be used for inlining. Resurrected tests, removed
spec-matrix for the moment. No review.
Diffstat (limited to 'test/files/run/Course-2002-10.scala')
-rw-r--r-- | test/files/run/Course-2002-10.scala | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/test/files/run/Course-2002-10.scala b/test/files/run/Course-2002-10.scala new file mode 100644 index 0000000000..e978bc8258 --- /dev/null +++ b/test/files/run/Course-2002-10.scala @@ -0,0 +1,135 @@ +//############################################################################ +// Programmation IV - 2002 - Week 10 +//############################################################################ + +import Math.{Pi, log} + +object M0 { + + def addStream (s1: Stream[Int], s2: Stream[Int]): Stream[Int] = + Stream.cons(s1.head + s2.head, addStream(s1.tail, s2.tail)); + + val fib: Stream[Int] = + Stream.cons(0, Stream.cons(1, addStream(this.fib, this.fib.tail))); + + def test = { + var i = 0; + fib.take(20).foreach(n => {Console.println("fib("+i+") = "+n); i=i+1}); + Console.println; + } +} + +//############################################################################ + +object M1 { + + def scale(x: Double, s: Stream[Double]): Stream[Double] = + s map { e: Double => e*x } + + def partialSums(s: Stream[Double]): Stream[Double] = + Stream.cons(s.head, partialSums(s.tail) map (x => x + s.head)); + + def euler(s: Stream[Double]): Stream[Double] = { + val nm1 = s apply 0; + val n = s apply 1; + val np1 = s apply 2; + Stream.cons(np1 - ((np1 - n)*(np1 - n) / (nm1 - 2*n + np1)),euler(s.tail)) + }; + + def better(s: Stream[Double], transform: Stream[Double] => Stream[Double]) + : Stream[Stream[Double]] = + Stream.cons(s, better(transform(s), transform)); + + def veryGood(s: Stream[Double], transform: Stream[Double] => Stream[Double]) + : Stream[Double] = + better(s, transform) map (x => x.head); + + def lnSummands(n: Double): Stream[Double] = + Stream.cons(1.0 / n, lnSummands(n + 1.0) map { x: Double => -x }) + + var ln0 = partialSums(lnSummands(1.0)); + var ln1 = euler(ln0); + var ln2 = veryGood(ln0, euler); + + def piSummands(n: Double): Stream[Double] = + Stream.cons(1.0 / n, piSummands(n + 2.0) map { x: Double => -x }) + + var pi0 = scale(4.0, partialSums(piSummands(1.0))); + var pi1 = euler(pi0); + var pi2 = veryGood(pi0, euler); + + def pad(s: String, n: Int): String = + if (n <= 0) s.substring(0, s.length() + n) + else pad(s + " ", n - 1); + def str(d: Double) = { val s = d.toString(); pad(s, 18 - s.length()) }; + + def test = { + var i = 0; + while (i < 10) { + Console.print("pi("+i+") = "); + Console.print(str(pi0.apply(i)) + ", "); + Console.print(str(pi1.apply(i)) + ", "); + Console.print(str(pi2.apply(i)) + "\n"); + i = i + 1; + } + Console.print("pi = "); + Console.print(str(Pi) + ", "); + Console.print(str(Pi) + ", "); + Console.print(str(Pi) + "\n"); + Console.println; + i = 0; + while (i < 10) { + Console.print("ln("+i+") = "); + Console.print(str(ln0.apply(i)) + ", "); + Console.print(str(ln1.apply(i)) + ", "); + Console.print(str(ln2.apply(i)) + "\n"); + i = i + 1; + } + Console.print("ln = "); + Console.print(str(log(2)) + ", "); + Console.print(str(log(2)) + ", "); + Console.print(str(log(2)) + "\n"); + Console.println; + } +} + +//############################################################################ + +object M2 { + + class IntIterator(start: Int) extends Iterator[Int] { + var current: Int = start; + def hasNext = true; + def next = { current = current + 1; current - 1 }; + } + + class PrimeIterator() extends Iterator[Int] { + var current: Iterator[Int] = new IntIterator(2); + def hasNext = true; + def next = { + val p = current.next; + current = current filter { x => !((x % p) == 0) }; + p + } + } + + def test = { + val i = (new PrimeIterator()).take(30); + Console.print("prime numbers:"); + while (i.hasNext) { Console.print(" " + i.next); } + Console.println; + } +} + +//############################################################################ + +object Test { + def main(args: Array[String]): Unit = { + M0.test; + M1.test; + M2.test; + () + } +} + +//############################################################################ |