Update to Python 3.9 (#1)

* Include parts of the gsee module as hard-code to workaround
  renewables-ninja/gsee/issues/12

draf/core/scenario.py

@@ -733,7 +733,7 @@ def get_meta(self, ent_name: str, meta_type: str) -> Optional[str]:
             obj = getattr(self, attr, None)
             if obj is not None:
                 metas = obj._meta.get(ent_name, "")
-                if metas is not "":
+                if metas != "":
                     return metas.get(meta_type, "")
         return None
 

draf/prep/gsee_module/cec_tools.py

@@ -0,0 +1,95 @@
+# This file was copied from the gsee repository
+# https://github.com/renewables-ninja/gsee/tree/2738600e64a645f97eb96f6c9fb7d3f2856cf24c
+# as a workaround to https://github.com/renewables-ninja/gsee/issues/12
+
+# This is the license of GSEE:
+
+# BSD 3-Clause License
+
+# Copyright (c) 2013-2018, Stefan Pfenninger
+# All rights reserved.
+
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+
+# * Redistributions of source code must retain the above copyright notice, this
+#   list of conditions and the following disclaimer.
+
+# * Redistributions in binary form must reproduce the above copyright notice,
+#   this list of conditions and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+
+# * Neither the name of the copyright holder nor the names of its
+#   contributors may be used to endorse or promote products derived from
+#   this software without specific prior written permission.
+
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import pvlib
+
+
+def get_efficiency(irradiance, cell_temperature, module_params):
+    """
+    irradiance : float or pandas.Series
+        Effective irradiance (W/m2) that is converted to photocurrent.
+    cell_temperature : float or pandas.Series
+        Average cell temperature of cells within a module in deg C.
+    module_params : dict
+        Module params 'alpha_sc', 'a_ref', 'I_L_ref', 'I_o_ref', 'R_sh_ref', 'R_s'.
+
+    """
+    params = pvlib.pvsystem.calcparams_desoto(
+        effective_irradiance=irradiance, temp_cell=cell_temperature, **module_params
+    )
+
+    # Ensure that the shunt resistance is not infinite
+    # Commented out because we want to still return valid Series when
+    # some of the values are zero -- NaNs from 0-divisions are filled later
+    # assert params[3] != math.inf
+
+    dc = pvlib.pvsystem.singlediode(*params)
+    efficiency = dc["p_mp"] / irradiance
+    return efficiency
+
+
+def relative_eff(irradiance, cell_temperature, params):
+    """
+    Compute relative efficiency of PV module as a function of irradiance
+    and cell/module temperature, from Huld (2010):
+
+    .. math:: n_{rel} = \frac{P_{stc} * (G / G_{stc})}{P}
+
+    Where G is in-plane irradiance, P is power output,
+    and STC conditions are :math:`G = 1000` and
+    :math:`T_{mod} = 25`.
+
+    When irradiance is zero, a zero relative efficiency is returned.
+
+    Parameters
+    ----------
+
+    irradiance : float or pandas.Series
+        Irradiance in W/m2.
+    cell_temperature : float or pandas.Series
+        Average cell temperature of cells within a module in deg C.
+    params : dict
+        Module params 'alpha_sc', 'a_ref', 'I_L_ref', 'I_o_ref', 'R_sh_ref', 'R_s'.
+
+    """
+    if isinstance(irradiance, float) and irradiance == 0:
+        return 0
+
+    power_stc = 1000 * get_efficiency(1000, 25, params)
+    power = irradiance * get_efficiency(irradiance, cell_temperature, params)
+
+    # Fill NaNs from any possible divisions by zero with 0
+    return (power / (power_stc * (irradiance / 1000))).fillna(0)