Merge branch 'updated_difffloat' into 'master'

Updated difffloat

Two changes:

 - By default, `testPair` does not produce cells with perturbed positions.
 - The difffloat script takes an additional (optional) argument to specify how many lines/particles have to be checked. I have updated the bash scripts to follow that new policy.

Re-assign to me if you are happy with it. Thanks !

See merge request !142

tests/difffloat.py

@@ -28,12 +28,18 @@ rel_tol = 1e-7
 # Comparisons are done both in absolute and relative terms
 
 # Individual tolerances for each column can be provided in a file
+# The (cube root of) the number of lines to check is provided as
+# an optional 4th argument
 
 file1 = sys.argv[1]
 file2 = sys.argv[2]
-fileTol = ""
+number_to_check = -1
+
+if len(sys.argv) == 5:
+    number_to_check = int(sys.argv[4])
 
-if len(sys.argv) == 4:
+fileTol = ""
+if len(sys.argv) >= 4:
     fileTol = sys.argv[3]
 
 data1 = loadtxt(file1)
@@ -67,8 +73,17 @@ else:
     absTol = dataTol[0,:]
     relTol = dataTol[1,:]
 
+n_lines_to_check = 0
+if number_to_check > 0:
+    n_lines_to_check = number_to_check**3
+    n_lines_to_check = min(n_lines_to_check, n_lines)
+    print "Checking the first %d particles."%n_lines_to_check
+else:
+    n_lines_to_check = n_lines
+    print "Checking all particles in the file."
+
 error = False
-for i in range(n_lines):
+for i in range(n_lines_to_check):
     for j in range(n_columns):
 
         abs_diff = abs(data1[i,j] - data2[i,j])
@@ -80,7 +95,7 @@ for i in range(n_lines):
             rel_diff = 0.
 
         if( abs_diff > absTol[j]):
-            print "Absolute difference larger than tolerance (%e) on line %d, column %d:"%(absTol[j], i,j)
+            print "Absolute difference larger than tolerance (%e) for particle %d, column %d:"%(absTol[j], i,j)
             print "%10s:           a = %e"%("File 1", data1[i,j])
             print "%10s:           b = %e"%("File 2", data2[i,j])
             print "%10s:       |a-b| = %e"%("Difference", abs_diff)
@@ -88,7 +103,7 @@ for i in range(n_lines):
             error = True
 
         if( rel_diff > relTol[j]):
-            print "Relative difference larger than tolerance (%e) on line %d, column %d:"%(relTol[j], i,j)
+            print "Relative difference larger than tolerance (%e) for particle %d, column %d:"%(relTol[j], i,j)
             print "%10s:           a = %e"%("File 1", data1[i,j])
             print "%10s:           b = %e"%("File 2", data2[i,j])
             print "%10s: |a-b|/|a+b| = %e"%("Difference", rel_diff)

tests/test27cells.sh

@@ -3,6 +3,6 @@ rm brute_force_27_standard.dat swift_dopair_27_standard.dat
 
 ./test27cells -p 6 -r 1 -d 0 -f standard
 
-python difffloat.py brute_force_27_standard.dat swift_dopair_27_standard.dat tolerance.dat
+python difffloat.py brute_force_27_standard.dat swift_dopair_27_standard.dat tolerance.dat 6
 
 exit $?

tests/test27cellsPerturbed.sh

@@ -3,6 +3,6 @@ rm brute_force_27_perturbed.dat swift_dopair_27_perturbed.dat
 
 ./test27cells -p 6 -r 1 -d 0.1 -f perturbed
 
-python difffloat.py brute_force_27_perturbed.dat swift_dopair_27_perturbed.dat tolerance.dat
+python difffloat.py brute_force_27_perturbed.dat swift_dopair_27_perturbed.dat tolerance.dat 6
 
 exit $?

tests/testPair.c

@@ -180,7 +180,7 @@ void runner_dopair1_density(struct runner *r, struct cell *ci, struct cell *cj);
 int main(int argc, char *argv[]) {
   size_t particles = 0, runs = 0, volume, type = 0;
   double offset[3] = {0, 0, 0}, h = 1.1255, size = 1., rho = 1.;
-  double perturbation = 0.1;
+  double perturbation = 0.;
   struct cell *ci, *cj;
   struct space space;
   struct engine engine;