warnings package:base R Documentation _P_r_i_n_t _W_a_r_n_i_n_g _M_e_s_s_a_g_e_s _D_e_s_c_r_i_p_t_i_o_n: 'warnings' and its 'print' method print the variable 'last.warning' in a pleasing form. _U_s_a_g_e: warnings(...) _A_r_g_u_m_e_n_t_s: ...: arguments to be passed to 'cat'. _D_e_t_a_i_l_s: See the description of 'options("warn")' for the circumstances under which there is a 'last.warning' object and 'warnings()' is used. In essence this is if 'options(warn = 0)' and 'warning' has been called at least once. It is possible that 'last.warning' refers to the last recorded warning and not to the last warning, for example if 'options(warn)' has been changed or if a catastrophic error occurred. _W_a_r_n_i_n_g: It is undocumented where 'last.warning' is stored nor that it is visible, and this is subject to change. Prior to R 2.4.0 it was stored in the workspace, but no longer. _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: 'warning'. _E_x_a_m_p_l_e_s: ## NB this example is intended to be pasted in, ## rather than run by example() ow <- options("warn") for(w in -1:1) { options(warn = w); cat("\n warn =",w,"\n") for(i in 1:3) { cat(i,"..\n"); m <- matrix(1:7, 3,4) } } warnings() options(ow) # reset