增加矩阵打印输出的宽度

When loading a matrix consisting of 12 columns into R, and then printing it, the terminal window in OS X cuts matrix in half, sort to speak, first showing all the rows with the initial 7 columns and then showing all the rows again with the remaining 5 columns. However, I would like it to display ll the columns, rather than dividing it up. How can I accomplish this?When loading a matrix consisting of 12 columns