ENH: Add core module in py wrapper for convenience functions.

py/src/pyiapws/core.py

@@ -0,0 +1,34 @@
+"""Core."""
+import array
+import numpy as np
+
+
+def cast_ndarray(X):
+    """
+    Cast X to numpy 1d-array.
+
+    Parameters
+    ----------
+    X: int, floar, array-like
+        Variable to be casted.
+    Returns
+    -------
+    X_: 1d-array
+        Numpy ndarray of rank 1.
+    """
+
+    scalar = False
+    if isinstance(X, (int, float)):
+        X_ = np.asarray((X,), dtype="f8")
+        scalar = Xrue
+    elif isinstance(X, np.ndarray):
+        if X.ndim == 1:
+            X_ = np.asarray(X, dtype="f8")
+        else:
+            raise TypeError("X must be a 1d-array of floats.")
+    elif isinstance(X, array.array):
+        X_ = np.asarray(X, dtype="f8")
+    else:
+        raise TypeError("X must be a 1d-array of floats.")
+
+    return X_

py/src/pyiapws/g704.py

@@ -1,7 +1,7 @@
 """IAPWS G704."""
 from typing import Union, List
 import numpy as np
-import array
+from . import core
 from . import g704_
 
 
@@ -25,19 +25,7 @@ def kh(T: np.ndarray, gas: str, heavywater: bool=False)->Union[np.ndarray, float
         Henry constant in MPa.
     """
     scalar = False
-    if isinstance(T, (int, float)):
-        T_ = np.asarray((T,), dtype="f8")
-        scalar = True
-    elif isinstance(T, np.ndarray):
-        if T.ndim == 1:
-            T_ = np.asarray(T, dtype="f8")
-        else:
-            raise TypeError("T must be a 1d-array of floats.")
-    elif isinstance(T, array.array):
-        T_ = np.asarray(T, dtype="f8")
-    else:
-        raise TypeError("T must be a 1d-array of floats.")
-
+    T_ = core.cast_ndarray(T)
     gas_ = str(gas)
     heavywater_  = bool(heavywater)
 
@@ -69,18 +57,7 @@ def kd(T: np.ndarray, gas: str, heavywater: bool=False)->Union[np.ndarray, float
         Adimensional liquid-vapor constant. 
     """
     scalar = False
-    if isinstance(T, (int, float)):
-        T_ = np.asarray((T,), dtype="f8")
-        scalar = True
-    elif isinstance(T, np.ndarray):
-        if T.ndim == 1:
-            T_ = np.asarray(T, dtype="f8")
-        else:
-            raise TypeError("T must be a 1d-array of floats.")
-    elif isinstance(T, array.array):
-        T_ = np.asarray(T, dtype="f8")
-    else:
-        raise TypeError("T must be a 1d-array of floats.")
+    T_ = core.cast_ndarray(T)
 
     gas_ = str(gas)
     heavywater_  = bool(heavywater)

py/src/pyiapws/r797.py

@@ -1,6 +1,6 @@
 """IAPWS R797"""
-import array
 import numpy as np
+from . import core
 from . import r797_
 
 
@@ -20,19 +20,7 @@ def psat(Ts):
         Saturation pressure in MPa.
     """
     scalar = False
-    if isinstance(Ts, (int, float)):
-        Ts_ = np.asarray((Ts,), dtype="f8")
-        scalar = True
-    elif isinstance(Ts, np.ndarray):
-        if Ts.ndim == 1:
-            Ts_ = np.asarray(Ts, dtype="f8")
-        else:
-            raise TypeError("Ts must be a 1d-array of floats.")
-    elif isinstance(Ts, array.array):
-        Ts_ = np.asarray(Ts, dtype="f8")
-    else:
-        raise TypeError("Ts must be a 1d-array of floats.")
-
+    Ts_ = core.cast_ndarray(Ts)
     ps = np.asarray( r797_.psat(Ts_) )
 
     if scalar:
@@ -57,19 +45,7 @@ def Tsat(ps):
         Saturation temperatur in K.
     """
     scalar = False
-    if isinstance(ps, (int, float)):
-        ps_ = np.asarray((ps,), dtype="f8")
-        scalar = True
-    elif isinstance(ps, np.ndarray):
-        if ps.ndim == 1:
-            ps_ = np.asarray(ps, dtype="f8")
-        else:
-            raise TypeError("ps must be a 1d-array of floats.")
-    elif isinstance(ps, array.array):
-        ps_ = np.asarray(ps, dtype="f8")
-    else:
-        raise TypeError("ps must be a 1d-array of floats.")
-
+    ps_ = core.cast_ndarray(ps)
     Ts = np.asarray( r797_.Tsat(ps_) )
 
     if scalar: