1 files changed, 18 insertions, 0 deletions
diff --git a/aircraftstudio/evaluator/dP.py b/aircraftstudio/evaluator/dP.py
new file mode 100644
index 0000000..b6aaa3b
--- /dev/null
+++ b/aircraftstudio/evaluator/dP.py
@@ -0,0 +1,18 @@
+def get_dx(self, component):
+    return [x - self.centroid[0] for x in component.x_start]
+
+
+def get_dz(self, component):
+    return [x - self.centroid[1] for x in component.x_start]
+
+
+def get_dP(self, xDist, zDist, V_x, V_z, area):
+    I_x = self.I_['x']
+    I_z = self.I_['z']
+    I_xz = self.I_['xz']
+    denom = float(I_x * I_z - I_xz**2)
+    z = float()
+    for _ in range(len(xDist)):
+        z += float(-area * xDist[_] * (I_x * V_x - I_xz * V_z) / denom -
+                   area * zDist[_] * (I_z * V_z - I_xz * V_x) / denom)
+    return z