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-rw-r--r--Lib/test/output/test_complex1
-rw-r--r--Lib/test/test_complex.py65
2 files changed, 66 insertions, 0 deletions
diff --git a/Lib/test/output/test_complex b/Lib/test/output/test_complex
new file mode 100644
index 0000000..b5224a9
--- /dev/null
+++ b/Lib/test/output/test_complex
@@ -0,0 +1 @@
+test_complex
diff --git a/Lib/test/test_complex.py b/Lib/test/test_complex.py
new file mode 100644
index 0000000..ef44fbc
--- /dev/null
+++ b/Lib/test/test_complex.py
@@ -0,0 +1,65 @@
+from test_support import TestFailed
+from random import random
+
+# XXX need many, many more tests here.
+
+nerrors = 0
+
+def check_close_real(x, y, eps=1e-12):
+ """Return true iff floats x and y "are close\""""
+ # put the one with larger magnitude second
+ if abs(x) > abs(y):
+ x, y = y, x
+ if y == 0:
+ return abs(x) < eps
+ if x == 0:
+ return abs(y) < eps
+ # check that relative difference < eps
+ return abs((x-y)/y) < eps
+
+def check_close(x, y, eps=1e-12):
+ """Return true iff complexes x and y "are close\""""
+ return check_close_real(x.real, y.real, eps) and \
+ check_close_real(x.imag, y.imag, eps)
+
+def test_div(x, y):
+ """Compute complex z=x*y, and check that z/x==y and z/y==x."""
+ global nerrors
+ z = x * y
+ if x != 0:
+ q = z / x
+ if not check_close(q, y):
+ nerrors += 1
+ print `z`, "/", `x`, "==", `q`, "but expected", `y`
+ if y != 0:
+ q = z / y
+ if not check_close(q, x):
+ nerrors += 1
+ print `z`, "/", `y`, "==", `q`, "but expected", `x`
+
+simple_real = [float(i) for i in range(-5, 6)]
+simple_complex = [complex(x, y) for x in simple_real for y in simple_real]
+for x in simple_complex:
+ for y in simple_complex:
+ test_div(x, y)
+
+# A naive complex division algorithm (such as in 2.0) is very prone to
+# nonsense errors for these (overflows and underflows).
+test_div(complex(1e200, 1e200), 1+0j)
+test_div(complex(1e-200, 1e-200), 1+0j)
+
+# Just for fun.
+for i in range(100):
+ test_div(complex(random(), random()),
+ complex(random(), random()))
+
+try:
+ z = 1.0 / (0+0j)
+except ZeroDivisionError:
+ pass
+else:
+ nerrors += 1
+ raise TestFailed("Division by complex 0 didn't raise ZeroDivisionError")
+
+if nerrors:
+ raise TestFailed("%d tests failed" % nerrors)