test_exp_cdc: fix python impl & print graphs into log

experiments/test_exp_cdc.sh

@@ -13,7 +13,7 @@ DOC="
   to be tested. If it is empty it defaults to
   $SIZES.
 
-  It requires geng from Nauty packaget to be in the PATH.
+  It requires geng from Nauty package to be in the PATH.
 
   WARNING: This experiment takes a long time to complete.
 "
@@ -28,13 +28,14 @@ fi
 
 : ${LOG:=${0%.sh}-$SIZES.log}
 : ${GENG:=geng}
+: ${PYTHON:=python}
 
 SELF="$(readlink -f "$0")"
 
 for s in $SIZES; do
   "$GENG" -Ctfd3D3 $s
 done |
-nice python /dev/fd/5 "$(dirname "$SELF")" "$LOG" 5<<'EOF' 
+nice $PYTHON /dev/fd/5 "$(dirname "$SELF")" "$LOG" 5<<'EOF'
 if True:
   import sys, os
   sys.path.append(sys.argv[1] + "/..")
@@ -53,6 +54,7 @@ if True:
     assert G.is_isomorphic(gadget.eval(UnderlayingGraph))
   
     j = {
+      "graph": G.sparse6_string(),
       "cdc_count": real,
       "n": G.num_verts(),
       "expected_cdc_lowerbound": exp,