--- a/scripts/quaternion/demoquat.m
+++ b/scripts/quaternion/demoquat.m
@@ -206,7 +206,7 @@
       [jvy,th] = quaternion(qtrans(jf,qyaw));
       qpitch = quaternion(jvy(1:3),thp*pi/180);
       qb = qmult(qpitch, qyaw);
-      qi = quaternion([1 0 0],180*degrees);
+      qi = quaternion([1, 0, 0],180*degrees);
     
       printf("yaw=%8.4f, pitch=%8.4f, \n    qbi = (%8.4f)i + (%8.4e)j + (%8.4f)k + (%8.4f)\n",thy,thp, ...
     	qb(1), qb(2), qb(3), qb(4));

--- a/scripts/quaternion/qcoordinate_plot.m
+++ b/scripts/quaternion/qcoordinate_plot.m
@@ -29,7 +29,7 @@
 
 # draw 1/3 circle in x-y plane around a unit z axis
 th = (0:-12:-120)*degrees*sign(th_eig);    lth = length(th);
-cpts = [0 0 0.1*cos(th) ; 0 0 0.1*sin(th); 0 1 1*ones(1,lth)];
+cpts = [0, 0, 0.1*cos(th) ; 0, 0, 0.1*sin(th); 0, 1, 1*ones(1,lth)];
 
 # rotate the 1/3 circle around eigenaxis of inertial to body rotation
 # qez = qe/qz = rotation to get from z axis to eigenaxis.

--- a/scripts/quaternion/quaternion.m
+++ b/scripts/quaternion/quaternion.m
@@ -30,12 +30,12 @@
     if(abs(theta) > pi)
       theta = theta - sign(theta)*pi;
     endif
-    sin_th_2 = norm([a b c]);
+    sin_th_2 = norm([a, b, c]);
 
     if(sin_th_2 != 0)
       vv = [a,b,c]/sin_th_2;
     else
-      vv = [a b c];
+      vv = [a, b, c];
     endif
     a = vv;
     b = theta;
@@ -76,7 +76,7 @@
   if ( !(is_scalar(w) & is_scalar(x) & is_scalar(y) & is_scalar(z)) )
     error("input values must be scalars.")
   endif
-  a = [w x y z];
+  a = [w, x, y, z];
 
 otherwise,
   error("usage: [a,b,c,d] = quaternion(w), a = quaternion(w,x,y,z)")