Document DEBUG usage and ordered-data generation in src/sorting/README and Makefile.

diff --git a/src/sorting/Makefile b/src/sorting/Makefile
index c85a83c09e5ea00842c70f702a8cbf23c1406f8b..4d84d0f25ac5ec13906b4971ced4ad7865ea01c9 100644 (file)
--- a/src/sorting/Makefile
+++ b/src/sorting/Makefile
@@ -2,7 +2,7 @@
 
 RM            = /bin/rm
 DATA_SIZE     = 8191  # the 5th Mersenne prime
-DATA          = data
+DATA          = data ordered-data
 
 # Non-MPI Environment
 
@@ -24,6 +24,9 @@ clean:
 data : data.py
        ./$< $(DATA_SIZE) > $@
 
+ordered-data : data.py
+       ./$< --ordered $(DATA_SIZE) > $@
+
 $(EXECS:%=%.o) main.o : %.o : %.c sort.h
        $(CC) -c $(CFLAGS) -o $@ $<
 

diff --git a/src/sorting/README b/src/sorting/README
index 4f619ffc6d00394b8405bb855d03b15cfbe5d7d7..e000dae3e67376c4b03668f9b75aea2c59cde0b5 100644 (file)
--- a/src/sorting/README
+++ b/src/sorting/README
@@ -22,7 +22,14 @@ Just run
 
     $ make
 
-which also builds a random data file 'data'.
+which also builds a random data file 'data'.  To build with the DEBUG
+macro defined (to enable some stderr printouts in main.c), run
+
+    $ make CFLAGS=-DDEBUG
+
+Remove auto-generated files with
+
+    $ make clean
 
 Usage
 -----
@@ -38,4 +45,11 @@ Timing 8191 data points on my 571 MHz netbook with
     $ time ./bubble data > /dev/null
     $ time ./quicksort data > /dev/null
 
-quicksort takes 0.075 s and bubble takes 3.994s.
+quicksort takes 0.075 s and bubble takes 3.994 s.
+
+On ordered data bubble does much better
+
+    $ time ./bubble ordered-data > /dev/null
+    $ time ./quicksort ordered-data > /dev/null
+
+quicksort takes 0.048 s and bubble takes 0.046 s.