print

 See [`print.default()`](https://www.rdocumentation.org/packages/base/topics/print.default) for more examples, particularly using other `...` arguments that aren't mentioned in the `print()` Usage. # Basic usage Under most circumstances, variables will automatically print their contents when you type their name. You can make this explicit by calling the `print()` function. ```{r} x <- pi ^ (1:5) x print(x) ``` If a variable name is typed from within a loop or a function ("not at the top-level"), then it won't print. In this case you have to explicitly call `print()` to print. ```{r} for(month in month.abb) { month } for(month in month.abb) { print(month) } ``` # Printing `factor`s ## `quote` argument By default, factor values and levels are printed without any quotes. By passing `quote = TRUE` you can make both elements and level be wrapped in double quotes. See also [`noquote()`](https://www.rdocumentation.org/packages/base/topics/noquote), which forces the strings to be printed without quotes. ```{r} numbers <- c("one", "two", "three", "four", "five", "six") dice <- factor(sample(numbers, 20, replace = TRUE), levels = numbers) print(dice) print(dice, quote = TRUE) ``` ## `max.levels` argument By default, `print()` will display as many factor [`levels()`](https://www.rdocumentation.org/packages/base/topics/levels) as will fit on one line. If you have many levels, sometimes you may wish to see more of them. On other occasions, you may not wish to see any of the levels. `max.levels` lets you choose how many levels will be printed. ```{r} x <- factor(rnorm(20)) print(x) # print 1 line of levels print(x, max.levels = 0) # print no levels print(x, max.levels = 20) # print all levels ``` ## `width` argument The `width` argument allows an alternate specification for how many levels are displayed. Whereas `max.levels` lets the user specify how many elements of `levels(x)` are displayed, `width` lets the user specify approximately how many _characters_ of `levels(x)` are displayed ```{r} x <- factor(rnorm(20)) print(x) # print 1 line of levels print(x, width = 0) # print first level print(x, width = 200) # print 200 char of levels ``` # Printing `table`s ## `digits` argument The `digits` argument controls the minimum number of significant digits displayed for numeric inputs. See [`print.default()`](https://www.rdocumentation.org/packages/base/topics/print.default) for examples of how this argument is used with numeric vector inputs. Under most circumstances, `table` object contain counts, so this argument is unnecessary. However, it is also possible to do arithmetic with tables, leading to non-integer values. ```{r} (x <- 1.234567 * table(sample(1:5, 100, replace = TRUE))) print(x, digits = 1) print(x, digits = 3) print(x, digits = 5) ``` ## `quote` argument This works in the same way as for `factor`s. Setting `quote = TRUE` means that the counts are displayed wrapped in double quotes. ```{r} (x <- table(sample(month.abb, 100, replace = TRUE))) print(x) print(x, quote = TRUE) ``` ## `na.print` argument As with the `digits` argument, usually `table` objects contain counts, so this argument is unneeded. If you do arithmetic on the table values, it is possible for `NA`s to occur. By default, these are displayed as blank values. You may prefer them to be displaed as `"NA"` (or any other value). ```{r} (x <- table(sample(month.abb, 100, replace = TRUE))) x[x < 8] <- NA print(x) print(x, na.print = "NA") ``` ## `zero.print` argument If you have an object with lots of zero values, it is sometimes easier to see what is happening by making those zeroes less conspicuous. `zero.print` let's you control what value is displayed; `"."` is a popular choice. ```{r} m1 <- sample(month.abb, 100, replace = TRUE) m2 <- sample(month.abb, 100, replace = TRUE) (x <- table(m1, m2)) print(x) print(x, zero.print = ".") ```