# Example 14: Page Break

### Handle Long Tables with Page Break

Page breaking will occur automatically if the table length exceeds the available page length. But page wrapping can also be controlled using the `page_break` parameter on the `define()` function. The `page_break` parameter identifies a column on which to break the page. The page will break every time the page break variable changes. You can use an existing variable or create a special variable just for the purpose of controlling the page breaks. If you create a special variable just for breaking the page, it is often desirable to make that column invisible. Here is an example:

    library(reporter)

    # Create temp file name
    tmp <- file.path(tempdir(), "example6.pdf")

    # Prepare data
    dat <- mtcars
    dat <- data.frame(vehicle = rownames(dat), dat,
                      page = c(rep(1, 10), rep(2, 12), rep(3, 10)))
    rownames(dat) <- NULL

    # View
    dat
    #                vehicle  mpg cyl  disp  hp drat    wt  qsec vs am gear carb page
    # 1            Mazda RX4 21.0   6 160.0 110 3.90 2.620 16.46  0  1    4    4    1
    # 2        Mazda RX4 Wag 21.0   6 160.0 110 3.90 2.875 17.02  0  1    4    4    1
    # 3           Datsun 710 22.8   4 108.0  93 3.85 2.320 18.61  1  1    4    1    1
    # 4       Hornet 4 Drive 21.4   6 258.0 110 3.08 3.215 19.44  1  0    3    1    1
    # 5    Hornet Sportabout 18.7   8 360.0 175 3.15 3.440 17.02  0  0    3    2    1
    # 6              Valiant 18.1   6 225.0 105 2.76 3.460 20.22  1  0    3    1    1
    # 7           Duster 360 14.3   8 360.0 245 3.21 3.570 15.84  0  0    3    4    1
    # 8            Merc 240D 24.4   4 146.7  62 3.69 3.190 20.00  1  0    4    2    1
    # 9             Merc 230 22.8   4 140.8  95 3.92 3.150 22.90  1  0    4    2    1
    # 10            Merc 280 19.2   6 167.6 123 3.92 3.440 18.30  1  0    4    4    1
    # 11           Merc 280C 17.8   6 167.6 123 3.92 3.440 18.90  1  0    4    4    2
    # 12          Merc 450SE 16.4   8 275.8 180 3.07 4.070 17.40  0  0    3    3    2
    # 13          Merc 450SL 17.3   8 275.8 180 3.07 3.730 17.60  0  0    3    3    2
    # 14         Merc 450SLC 15.2   8 275.8 180 3.07 3.780 18.00  0  0    3    3    2
    # 15  Cadillac Fleetwood 10.4   8 472.0 205 2.93 5.250 17.98  0  0    3    4    2
    # 16 Lincoln Continental 10.4   8 460.0 215 3.00 5.424 17.82  0  0    3    4    2
    # 17   Chrysler Imperial 14.7   8 440.0 230 3.23 5.345 17.42  0  0    3    4    2
    # 18            Fiat 128 32.4   4  78.7  66 4.08 2.200 19.47  1  1    4    1    2
    # 19         Honda Civic 30.4   4  75.7  52 4.93 1.615 18.52  1  1    4    2    2
    # 20      Toyota Corolla 33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1    2
    # 21       Toyota Corona 21.5   4 120.1  97 3.70 2.465 20.01  1  0    3    1    2
    # 22    Dodge Challenger 15.5   8 318.0 150 2.76 3.520 16.87  0  0    3    2    2
    # 23         AMC Javelin 15.2   8 304.0 150 3.15 3.435 17.30  0  0    3    2    3
    # 24          Camaro Z28 13.3   8 350.0 245 3.73 3.840 15.41  0  0    3    4    3
    # 25    Pontiac Firebird 19.2   8 400.0 175 3.08 3.845 17.05  0  0    3    2    3
    # 26           Fiat X1-9 27.3   4  79.0  66 4.08 1.935 18.90  1  1    4    1    3
    # 27       Porsche 914-2 26.0   4 120.3  91 4.43 2.140 16.70  0  1    5    2    3
    # 28        Lotus Europa 30.4   4  95.1 113 3.77 1.513 16.90  1  1    5    2    3
    # 29      Ford Pantera L 15.8   8 351.0 264 4.22 3.170 14.50  0  1    5    4    3
    # 30        Ferrari Dino 19.7   6 145.0 175 3.62 2.770 15.50  0  1    5    6    3
    # 31       Maserati Bora 15.0   8 301.0 335 3.54 3.570 14.60  0  1    5    8    3
    # 32          Volvo 142E 21.4   4 121.0 109 4.11 2.780 18.60  1  1    4    2    3

    # Define table
    tbl <- create_table(dat) %>%
      define(vehicle, label = "Vehicle", width = 2, align = "left") |>
      define(page, page_break = TRUE, visible = FALSE)

    # Create the report
    rpt <- create_report(tmp, output_type = "PDF",
                         font = "Courier", font_size = 12) |>
      titles("Listing 2.0", "MTCARS Data Listing with Page Break") |>
      set_margins(top = 1, bottom = 1) |>
      add_content(tbl) |>
      page_footer(right = "Page [pg] of [tpg]")

    # Write the report
    write_report(rpt)

    # file.show(tmp)

Also note that automatic page breaking can be turned off, if desired.
See the vignette Example 18: Report Options for a demonstration.

Next: Example 15: Header and Footer Images