new helpers dict_to_xarray and float_round including tests and doc

src/helpers.py

@@ -5,16 +5,19 @@ __date__ = '2019-10-21'
 
 
 import logging
-import keras
-import keras.backend as K
 import math
-from typing import Union
-import numpy as np
 import os
 import time
 import socket
 import datetime as dt
 
+import keras
+import keras.backend as K
+import numpy as np
+import xarray as xr
+
+from typing import Union, Dict, Callable
+
 
 def to_list(arg):
     if not isinstance(arg, list):
@@ -197,3 +200,35 @@ class PyTestRegex:
 
     def __repr__(self) -> str:
         return self._regex.pattern
+
+
+def dict_to_xarray(d: Dict, coordinate_name: str) -> xr.DataArray:
+    """
+    Convert a dictionary of 2D-xarrays to single 3D-xarray. The name of new coordinate axis follows <coordinate_name>.
+    :param d: dictionary with 2D-xarrays
+    :param coordinate_name: name of the new created axis (2D -> 3D)
+    :return: combined xarray
+    """
+    xarray = None
+    for k, v in d.items():
+        if xarray is None:
+            xarray = v
+            xarray.coords[coordinate_name] = k
+        else:
+            tmp_xarray = v
+            tmp_xarray.coords[coordinate_name] = k
+            xarray = xr.concat([xarray, tmp_xarray], coordinate_name)
+    return xarray
+
+
+def float_round(number: float, decimals: int = 0, round_type: Callable = math.ceil) -> float:
+    """
+    Perform given rounding operation on number with the precision of decimals.
+    :param number: the number to round
+    :param decimals: numbers of decimals of the rounding operations (default 0 -> round to next integer value)
+    :param round_type: the actual rounding operation. Can be any callable function like math.ceil, math.floor or python
+        built-in round operation.
+    :return: rounded number with desired precision
+    """
+    multiplier = 10. ** decimals
+    return round_type(number * multiplier) / multiplier

test/test_helpers.py

@@ -189,3 +189,55 @@ class TestSetExperimentName:
     def test_set_experiment_from_sys(self):
         exp_name, _ = set_experiment_name(experiment_date="2019-11-14")
         assert exp_name == "2019-11-14_network"
+
+
+class TestPytestRegex:
+
+    @pytest.fixture
+    def regex(self):
+        return PyTestRegex("teststring")
+
+    def test_pytest_regex_init(self, regex):
+        assert regex._regex.pattern == "teststring"
+
+    def test_pytest_regex_eq(self, regex):
+        assert regex == "teststringabcd"
+        assert regex != "teststgabcd"
+
+    def test_pytest_regex_repr(self, regex):
+        assert regex.__repr__() == "teststring"
+
+
+class TestDictToXarray:
+
+    def test_dict_to_xarray(self):
+        array1 = xr.DataArray(np.random.randn(2, 3), dims=('x', 'y'), coords={'x': [10, 20]})
+        array2 = xr.DataArray(np.random.randn(2, 3), dims=('x', 'y'), coords={'x': [10, 20]})
+        d = {"number1": array1, "number2": array2}
+        res = dict_to_xarray(d, "merge_dim")
+        assert type(res) == xr.DataArray
+        assert sorted(list(res.coords)) == ["merge_dim", "x"]
+        assert res.shape == (2, 2, 3)
+
+
+class TestFloatRound:
+
+    def test_float_round_ceil(self):
+        assert float_round(4.6) == 5
+        assert float_round(239.3992) == 240
+
+    def test_float_round_decimals(self):
+        assert float_round(23.0091, 2) == 23.01
+        assert float_round(23.1091, 3) == 23.11
+
+    def test_float_round_type(self):
+        assert float_round(34.9221, 2, math.floor) == 34.92
+        assert float_round(34.9221, 0, math.floor) == 34.
+        assert float_round(34.9221, 2, round) == 34.92
+        assert float_round(34.9221, 0, round) == 35.
+
+    def test_float_round_negative(self):
+        assert float_round(-34.9221, 2, math.floor) == -34.93
+        assert float_round(-34.9221, 0, math.floor) == -35.
+        assert float_round(-34.9221, 2) == -34.92
+        assert float_round(-34.9221, 0) == -34.