Fixed typos.

Ri2e.m

@@ -4,7 +4,7 @@ function RotMati2e = Ri2e(grace_gps_time)
 % to an Earth-fixed Earth-centered coordinate system. The rotation matrix
 % is a simple Z-rotation, in which the rotation axes of the inertial and
 % the Earth-fixed frames coincide. It is an approximation of the realistic
-% rotation matrix, by neglecting the contribuiton of the Precession, 
+% rotation matrix, by neglecting the contribution of the Precession, 
 % Nutation and polar motion.
 
 % INPUT arguments:

Ri2srf.m

 function RotMat_i2srf = Ri2srf(Q)
 
 % this function computes the rotation matrix from inertial frame to
-% satellite reference frame (SRF) based on the given quatrnions Q.
+% satellite reference frame (SRF) based on the given quaternions (Q).
 %
 % INPUT:
 %       quaterninons Q = [Q1, Q2, Q3, Q4] ... where Q4 = Q0 = cos(phi/2)