Expression

An expression is composed of objects and operators. Objects in expression could be constant, variable, function, expression, etc.

$ 3>2;
1

$ x=true;
$ !x;
0

$ x=1 2 3
$ x*2;
[2,4,6]

$ y = 4 5 6;
$ x+y;
[5,7,9]

$ x+y*2;

$ (y-avg(y))*(y-avg(y));
[1,0,1]

$ t1 = table(x,y);
$ t1.y[0]\sum(t1.y);
0.266667