Self-study note: Playing with SAS.

basic_op.sas

d = {
	0 1 0 0,
	2 1 0 0,
	0 1 0 4
};

e = d`;
e2 = t(d);

a = {
	1 2,
	3 4
};

b = {
	5 6,
	7 8
};

b2 = a # b;
sum = sum(b2);

c = a * b;
d = a * inv(b);
e = a / b;

basic_op2.sas

a = {
  1 2,
  3 4
};

b = det(a);
c = int(a);
d = a * c;


a = {
  1 2,
  3 4
};

b = {
  5 6,
  7 8
};


TRA = trace(a);
TRB = trace(b);
TRA_B = trace(a + b)
TRAB = trace(a * b)
TRBA = trace(b * a)

est_by_matrix.sas

proc iml; reset print;

X = {
  1 1,
  1 1,
  1 2,
  1 2,
  1 3,
  1 3
};

Y = {1, 2, 1, 3, 2, 3};

Xr = nrow(X);
Xc = ncol(X);
XX = X` * X;
XY = X` * Y;
i_XX = inv(XX);
b = i_XX * XY;
Yhat = X * b;
e = Y - Yhat;

est_by_proc.sas

data data;
  input x y;
cards;
 1  1
 1  2
 2  1
 2  3
 3  2
 3  3
;

proc reg data = data;
  model y = x;
run;

practices.sas

* Practice 1;

A = {
  1 2 1,
  2 3 1,
  1 2 2
};


TRA = trace(A);
dA = det(A);
iA = inv(A);

* Practice 2;

B = {
   2  1 -3,
  -1  2  1,
  3  -1  2
};

C = {
  -12,
  7,
  -1
};

D = inv(B) * C;

reset.sas

proc iml;
reset print;
a = 2;
print a;