p1 <- ggplot(mtcars, aes(mpg, cyl)) + geom_point()
p2 <- ggplot(mtcars, aes(mpg, cyl)) + geom_line()
p3 <- ggplot(mtcars, aes(mpg, cyl)) + geom_line(color="blue")
p4 <- ggplot(mtcars, aes(mpg, cyl)) + geom_line(color="red")

library(ggplot2)
    library(gridExtra)

    # Crio 4 gráficos
    grafico_1 <- qplot(1:5,1:5)
    grafico_2 <- qplot(10:1,1:10)
    grafico_3 <- qplot(1)
    grafico_4 <- qplot(12)

    # Plotando dois deles (em colunas)
    grid.arrange(grafico_1 , grafico_2 , ncol=2)

    # Plotando outros dois (em linhas)
    grid.arrange(grafico_3 , grafico_4 , nrow=2)


    # Plotando todos
    grid.arrange(grafico_1 , grafico_2 ,
                 grafico_3 , grafico_4 ,
                 ncol=2, nrow=2)

# Multiple plot function
#
# ggplot objects can be passed in ..., or to plotlist (as a list of ggplot objects)
# - cols:   Number of columns in layout
# - layout: A matrix specifying the layout. If present, 'cols' is ignored.
#
# If the layout is something like matrix(c(1,2,3,3), nrow=2, byrow=TRUE),
# then plot 1 will go in the upper left, 2 will go in the upper right, and
# 3 will go all the way across the bottom.
#
multiplot <- function(..., plotlist=NULL, file, cols=1, layout=NULL) {
  require(grid)

  # Make a list from the ... arguments and plotlist
  plots <- c(list(...), plotlist)

  numPlots = length(plots)

  # If layout is NULL, then use 'cols' to determine layout
  if (is.null(layout)) {
    # Make the panel
    # ncol: Number of columns of plots
    # nrow: Number of rows needed, calculated from # of cols
    layout <- matrix(seq(1, cols * ceiling(numPlots/cols)),
                    ncol = cols, nrow = ceiling(numPlots/cols))
  }

 if (numPlots==1) {
    print(plots[[1]])

  } else {
    # Set up the page
    grid.newpage()
    pushViewport(viewport(layout = grid.layout(nrow(layout), ncol(layout))))

    # Make each plot, in the correct location
    for (i in 1:numPlots) {
      # Get the i,j matrix positions of the regions that contain this subplot
      matchidx <- as.data.frame(which(layout == i, arr.ind = TRUE))

      print(plots[[i]], vp = viewport(layout.pos.row = matchidx$row,
                                      layout.pos.col = matchidx$col))
    }
  }
}

library(gridExtra)

p1 <- ggplot(mtcars, aes(mpg, cyl)) + geom_point()
p2 <- ggplot(mtcars, aes(mpg, cyl)) + geom_line()
p3 <- ggplot(mtcars, aes(mpg, cyl)) + geom_line(color="blue")
p4 <- ggplot(mtcars, aes(mpg, cyl)) + geom_line(color="red")

grid.arrange(p1,p2, p3, p4)

library(tips)
library(ggplot2)

data(tips)
head(tips)

total_bill  tip    sex smoker day   time size
1      16.99 1.01 Female     No Sun Dinner    2
2      10.34 1.66   Male     No Sun Dinner    3
3      21.01 3.50   Male     No Sun Dinner    3
4      23.68 3.31   Male     No Sun Dinner    2
5      24.59 3.61 Female     No Sun Dinner    4
6      25.29 4.71   Male     No Sun Dinner    4

g1 <- ggplot(tips, aes(x=total_bill, y=tip/total_bill)) + geom_point(shape=1)

g1 + facet_grid(. ~ sex)

ggplot(tips, aes(x=total_bill, y=tip/total_bill, fill=sex, col=sex)) + geom_point(shape=1) + geom_smooth()

library(ggplot2)

p1 <- ggplot(mtcars, aes(mpg, cyl)) + geom_point()
p2 <- ggplot(mtcars, aes(mpg, cyl)) + geom_line()
p3 <- ggplot(mtcars, aes(mpg, cyl)) + geom_line(color="blue")
p4 <- ggplot(mtcars, aes(mpg, cyl)) + geom_line(color="red")

library(cowplot)
cowplot::plot_grid(p1, p2, p3, p4,
                   nrow = 2, align = "hv")

library(ggpubr)
ggpubr::ggarrange(p1, p2, p3, p4,
                  nrow = 2, ncol = 2)

library(patchwork)
p1 + p2 + p3 + p4

library(egg)
egg::ggarrange(p1, p2, p3, p4, ncol = 2)

library(gridExtra)
# Matriz para divisao do plot
lay <- rbind(c(1,2),
             c(3,4))

gridExtra::grid.arrange(p1, p2, p3, p4, layout_matrix = lay)