Syntax package:base R Documentation _O_p_e_r_a_t_o_r _S_y_n_t_a_x _a_n_d _P_r_e_c_e_d_e_n_c_e _D_e_s_c_r_i_p_t_i_o_n: Outlines R syntax and gives the precedence of operators _D_e_t_a_i_l_s: The following unary and binary operators are defined. They are listed in precedence groups, from highest to lowest. '[ [[' indexing ':: :::' access variables in a name space '$ @' component / slot extraction '^' exponentiation (right to left) '- +' unary minus and plus ':' sequence operator '%any%' special operators '* /' multiply, divide '+ -' (binary) add, subtract '< > <= >= == !=' ordering and comparison '!' negation '& &&' and '| ||' or '~' as in formulae '-> ->>' rightwards assignment '=' assignment (right to left) '<- <<-' assignment (right to left) '?' help (unary and binary) Within an expression operators of equal precedence are evaluated from left to right except where indicated. The links in the *See Also* section cover most other aspects of the basic syntax. _N_o_t_e: There are substantial precedence differences between R and S. In particular, in S '?' has the same precedence as (binary) '+ -' and '& && | ||' have equal precedence. _R_e_f_e_r_e_n_c_e_s: Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) _The New S Language_. Wadsworth & Brooks/Cole. _S_e_e _A_l_s_o: 'Arithmetic', 'Comparison', 'Control', 'Extract', 'Logic', 'NumericConstants', 'Paren', 'Quotes', 'Reserved'. The _R Language Definition_ manual.