refine testcase for random

Author: syheliel

integration_tests/test_random_02.py

@@ -1,11 +1,21 @@
-from lpython import f64
+from lpython import i32, f64
 import random
 
 def test_seed():
-    random.seed()
-    t1: f64 = random.random()
-    t2: f64 = random.random()
-    print(t1, t2)
-    assert abs(t1 - t2) > 1e-3
+    """test the distribution of random"""
+    num_samples:i32 = 100000
+    bins: list[i32] = [0]*10
+    _ : i32
+    for _ in range(num_samples):
+        val: f64 = random.random()
+        assert val >= 0.0 and val < 1.0  # value out of range
+        bins[i32(val * 10.0)] += 1  # increment the appropriate bin
+
+    # Check that no bin has significantly more or fewer values than expected
+    expected_bin_count:i32 = i32(num_samples / 10)
+    count : i32
+    for count in bins:
+        blas: f64 = f64(abs(count - expected_bin_count))
+        assert blas < f64(expected_bin_count) * 0.05  # allow 5% deviation
 
 test_seed()