Feat: Optimace CalDB requests

@ahmedk @haufs Number of requests to the calibration DB is significantly reduced.

cal_tools/cal_tools/ana_tools.py

@@ -135,6 +135,50 @@ def recursively_save_dict_contents_to_group(h5file, path, dic):
             raise ValueError('Cannot save %s type.' % type(item))
 
 
+def combine_lists(*args, names=None):
+    """
+    Combine several lists to a list of dictionary or a list of lists
+    Each dictionary contain a set of elements, one from each list
+
+    :param args: several lists to be combined
+    :param names: list of names (the length equal to the number of args)
+    :return: list of dictionary of list of lists
+
+    Example:
+    .. code-block:: python
+
+        # define input lists
+        a = [100,200]
+        b = [0,1,2]
+        c = [25]
+
+        comb = combine_lists(a,b,c)
+        # comb: [[100, 0, 25], [100, 1, 25], [100, 2, 25],
+        #        [200, 0, 25], [200, 1, 25], [200, 2, 25]]
+
+        comb = combine_lists(a,b,c, names=['Voltage', 'Gain', 'Temperature'])
+        # comb: [{'Voltage': 100, 'Gain': 0, 'Temperature': 25},
+        #        {'Voltage': 100, 'Gain': 1, 'Temperature': 25},
+        #        {'Voltage': 100, 'Gain': 2, 'Temperature': 25},
+        #        {'Voltage': 200, 'Gain': 0, 'Temperature': 25},
+        #        {'Voltage': 200, 'Gain': 1, 'Temperature': 25},
+        #        {'Voltage': 200, 'Gain': 2, 'Temperature': 25}]
+    """
+
+    params = list(map(tuple, args))
+    possible_params = [[]]
+    for param in params:
+        possible_params = [x + [y] for x in possible_params for y in param]
+
+    if isinstance(names, (list, tuple)):
+        assert len(names) == len(args)
+        d_possible_params = []
+        for par in possible_params:
+            d_possible_params.append(dict(zip(names, par)))
+        return d_possible_params
+    return possible_params
+
+
 def combine_constants(ctimes_a, ctimes_b):
     """
     Combine two numpy arrays of timestamp