Problem 5

README.md

@@ -3,6 +3,7 @@ ME 3255
 Homework 5
 
 ##Problem 2
+
 Least Squares function
 ```matlab
 function [a,fx,r2] = least_squares(Z,y);
@@ -159,6 +160,14 @@ Output:
 - L = 5.0108 m
 #Problem 5
 ###Part A
+```matlab
+cd_out_linear = sphere_drag(300,'linear') = 0.1750
+cd_out_spline = sphere_drag(300,'spline') = 0.1809
+cd_out_pchip = sphere_drag(300,'pchip') = 0.1807
+```
+
+### Part B
+![Drag Force vs. Velocity  (3 Interpolation Methods)](./figure5.png)
 
 #Problem 6
 ###Analytical
@@ -190,7 +199,7 @@ tildex = (b-a)/2*x + (b+a)/2;
 f = (1/6).*(tildex).^3+(1/2).*(tildex).^2+(tildex);
 value2 = sum(tildec.*f)
 ```
-###3-point
+##3-point
 ```matlab
 %Three Point
 x = [-0.77459666,0,0.77459666];

sphere_drag.m

@@ -1,10 +1,26 @@
 function [Cd_out] = sphere_drag(Re_in,spline_type)
     % interpolation for drag coeff based upon Reynolds number
-    % output is 
+    % output is
     % Cd: drag coeff
-    % input is 
+    % input is
     % Re_in: Reynolds number
-    % and 
+    % and
     % spline_type: 'linear', 'cubic', or 'spline'/'pchip'
-
-
+
+    %function [Cd_out]=sphere_drag(Re_in,spline_type)
+    data = [2	0.52
+    5.8	0.52
+    16.8	0.52
+    27.2	0.5
+    29.9	0.49
+    33.9	0.44
+    36.3	0.18
+    40	0.074
+    46	0.067
+    60	0.08
+    100	0.12
+    200	0.16
+    400	0.19];
+
+    Cd_out = interp1(data(:,1),data(:,2),Re_in,spline_type);
+end