Update test script (infiniflow#1722)

### What problem does this PR solve?

Update test script
Remove "+" in float exponent part

### Type of change

- [x] Test cases

tools/generate_multivector_knn_scan.py

@@ -3,6 +3,18 @@
 import random
 from math import sin, cos, acos, pi
 import numpy as np
+import string
+
+
+class MyFormatter(string.Formatter):
+    def format_field(self, value, format_spec):
+        if format_spec == 'm':
+            return super().format_field(value, 'e').replace('e+', 'e')
+        else:
+            return super().format_field(value, format_spec)
+
+
+fmt = MyFormatter()
 
 
 def get_sphere_point(r, rand1, rand2):
@@ -15,11 +27,11 @@ def get_sphere_point(r, rand1, rand2):
 
 
 row_n = 1000
-query_data = [3, 500, 990, random.randint(0, row_n - 1)]
-top_n = [5, 255, 256, row_n]
+query_data = [random.randint(0, row_n - 1), 3, 500, 990]
+top_n = [row_n, 5, 255, 256]
 num_in_row = 10
 radius = 10000.0
-require_min_diff = 1e-6
+require_min_diff = 1e-5
 
 
 def get_numpy_l2_norm(v1: np.ndarray, v2: np.ndarray):
@@ -44,7 +56,7 @@ def get_random_data():
         # check query result for query_data, return if all query distances are different
         distance_results = []
         good_diff = True
-        for i in query_data:
+        for pos, i in enumerate(query_data):
             query_v = all_multivector_centers[i]
             distance_pair = []
             for j in range(row_n):
@@ -53,7 +65,7 @@ def get_random_data():
                 distance_pair.append((j, np.min(l2_d)))
             # sort by distance
             distance_pair.sort(key=lambda x: x[1])
-            for j in range(row_n - 1):
+            for j in range(min(row_n - 1, top_n[pos])):
                 if (distance_pair[j + 1][1] - distance_pair[j][1]) / distance_pair[j + 1][1] < require_min_diff:
                     good_diff = False
                     break
@@ -127,7 +139,8 @@ def write_twice(statement: str, output_table_name: bool = False):
         write_twice("\n# multivector scan\n")
         for i, q_id in enumerate(query_data):
             write_twice("\nquery I\n")
-            query_v = np.array2string(all_multivector_centers[q_id], separator=',')
+            query_v = np.array2string(all_multivector_centers[q_id], separator=',',
+                                      formatter={'float': lambda x: fmt.format_field(x, 'm')})
             query_str = f"SELECT c1 FROM \u007b\u007d SEARCH MATCH VECTOR (c2, {query_v}, 'float', 'l2', {top_n[i]});\n"
             write_twice(query_str, True)
             write_twice("----\n")