Merge pull request #1508 from pllim/add-timer

Move timer functions from astropy

Author: bsipocz

CHANGES.rst

@@ -150,6 +150,8 @@ ukidss
 utils
 ^^^^^
 
+- Added timer functions. [#1508]
+
 vamdc
 ^^^^^
 

astroquery/utils/tests/test_timer.py

@@ -0,0 +1,90 @@
+# Licensed under a 3-clause BSD style license - see LICENSE.rst
+"""Test `astroquery.utils.timer`.
+
+.. note::
+
+    The tests only compare rough estimates as
+    performance is machine-dependent.
+
+"""
+
+# STDLIB
+import time
+
+# THIRD-PARTY
+import pytest
+import numpy as np
+from astropy.utils.exceptions import AstropyUserWarning
+from astropy.modeling.fitting import ModelsError
+
+# LOCAL
+from ..timer import RunTimePredictor
+
+
+def func_to_time(x):
+    """This sleeps for y seconds for use with timing tests.
+
+    .. math::
+
+        y = 5 * x - 10
+
+    """
+    y = 5.0 * np.asarray(x) - 10
+    time.sleep(y)
+    return y
+
+
+def test_timer():
+    """Test function timer."""
+    p = RunTimePredictor(func_to_time)
+
+    # --- These must run before data points are introduced. ---
+
+    with pytest.raises(ValueError):
+        p.do_fit()
+
+    with pytest.raises(RuntimeError):
+        p.predict_time(100)
+
+    # --- These must run next to set up data points. ---
+
+    with pytest.warns(AstropyUserWarning, match="ufunc 'multiply' did not "
+                      "contain a loop with signature matching types"):
+        p.time_func([2.02, 2.04, 2.1, 'a', 2.3])
+    p.time_func(2.2)  # Test OrderedDict
+
+    assert p._funcname == 'func_to_time'
+    assert p._cache_bad == ['a']
+
+    k = list(p.results.keys())
+    v = list(p.results.values())
+    np.testing.assert_array_equal(k, [2.02, 2.04, 2.1, 2.3, 2.2])
+    np.testing.assert_allclose(v, [0.1, 0.2, 0.5, 1.5, 1.0])
+
+    # --- These should only run once baseline is established. ---
+
+    with pytest.raises(ModelsError):
+        a = p.do_fit(model='foo')
+
+    with pytest.raises(ModelsError):
+        a = p.do_fit(fitter='foo')
+
+    a = p.do_fit()
+
+    assert p._power == 1
+
+    # Perfect slope is 5, with 10% uncertainty
+    assert 4.5 <= a[1] <= 5.5
+
+    # Perfect intercept is -10, with 1-sec uncertainty
+    assert -11 <= a[0] <= -9
+
+    # --- These should only run once fitting is completed. ---
+
+    # Perfect answer is 490, with 10% uncertainty
+    t = p.predict_time(100)
+    assert 441 <= t <= 539
+
+    # Repeated call to access cached run time
+    t2 = p.predict_time(100)
+    assert t == t2