initial commit / add all books

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+
+//Variable Declaration
+
+rI=-4685.3  //I component of radius vector from Example 2.16(km)
+rJ=5047.7   //J component of radius vector from Example 2.16(km)
+rK=-3289.1  //K component of radius vector from Example 2.16(km)
+aE=6378.1414 //Semimajor axis (km)
+eE=0.08182   //Eccentricity
+
+//Calculation
+
+r=sqrt(rI**2+rJ**2+rK**2)
+a=%pi  //Guess value for LST(radians)
+b=atan(rK/rI)   //Guess Value for latitude(radians)
+c=r-aE   //Guess value for height(km)
+
+function [ans] = equations(p)
+    L = p(1)
+    h = p(2)
+    LST = p(3)
+    a = rI-((aE/sqrt(1-eE**2*sin(L)**2))+h)*cos(L)*cos(LST)
+    b = rJ-((aE/sqrt(1-eE**2*sin(L)**2))+h)*cos(L)*sin(LST)
+    c = rK-((aE*(1-eE**2)/sqrt(1-eE**2*sin(L)**2))+h)*sin(L)
+    ans = [a;b;c]
+endfunction
+
+ans =  fsolve([b;c;a],equations)
+L = ans(1)
+h = ans(2)
+LST = ans(3)
+L= L*180/3.142  //Converting L into degrees
+h=round(h)
+LST=LST*180/3.142 //Converting LST into degrees
+
+printf("The latitude of subsatellite is %.2f degrees",L)
+printf("\nThe height of subsatellite is %.2f km",h)
+printf("\nThe LST of subsatellite is %.1f degrees",LST)