r - Save facet_wrap() on multiple pages using ggforce/ggplus

Question

I got this plot using the code below

library(tidyverse)
ggplot(df2, aes(x =Date, y = Sales, color = id))+ 
  geom_line(size = 0.01, alpha = 0.3)+
  +facet_wrap(~id)
  scale_x_date(breaks = seq(as.Date("2001-01-01"),
                            as.Date("2007-01-01"), by="1 year"),
               labels = date_format("%Y"))

In my original data, I have 30 levels for the id. If I plot all facets on one page, it will be so messy and difficult to read. Therefore, I want to have a plot similar to the plot above but 4 facets only on each page so it will be readable.

I used ggplus package to do so.

#devtools::install_github("guiastrennec/ggplus")
library(ggplus)
p <- ggplot(df2, aes(x =Date, y = Sales))+ 
  geom_line(size = 0.01, alpha = 0.3)+
  scale_x_date(breaks = seq(as.Date("2001-01-01"),
                            as.Date("2007-01-01"), by="1 year"),
               labels = date_format("%Y"))

facet_multiple(plot = p, 
               facets = "id", 
               ncol = 2, 
               nrow = 2)

If there is no NA, it works fine and I got the plot on two pages. However, as my data have NAs, I got this error

Error in if (zero_range(range)) { : missing value where TRUE/FALSE needed

I will appreciate any suggestions to fix this error.

DATA

Date <- as.Date(c(seq(as.Date("2001-01-03"), as.Date("2006-10-17"), by = 1), 
                  seq(as.Date("2001-05-10"), as.Date("2006-12-17"), by = 1),  
                  seq(as.Date("2001-04-12"), as.Date("2006-11-17"), by = 1),
                  seq(as.Date("2001-03-12"), as.Date("2006-10-12"), by = 1),
                  seq(as.Date("2001-01-12"), as.Date("2006-11-03"), by = 1),
                  seq(as.Date("2001-03-11"), as.Date("2006-10-21"), by = 1),
                  seq(as.Date("2001-02-14"), as.Date("2006-11-25"), by = 1),
                  seq(as.Date("2001-04-22"), as.Date("2006-12-27"), by = 1)))
id  <- c(rep("AAA", 2114), rep("BBB", 2048), rep("CCC", 2046), rep ("DDD", 2041), rep ("EEE", 2122), rep ("FFF", 2051), rep ("GGG", 2111) , rep ("HHH", 2076))
Sales <- c(sample(10:20, 2114, replace = T), sample(50:60, 2048, replace = T), sample(80:90, 2046, replace = T), sample(80:90, 2041, replace = T),
           sample(12:70, 2122, replace = T), sample(30:90, 2051, replace = T), sample(15:70, 2111, replace = T), sample(100:120, 2076, replace = T))
df <- data.frame(id , Date, Sales)

df1 <- df[c(1:50, 1050:2000, 3000:3600, 4000:4350, 6000:6400, 9000:9700, 10456:11254, 12000:12850, 14500:15200),] %>% 
  tidyr::spread(id, Sales)

df2 <- data.frame(Date = seq(as.Date("2001-01-01"), as.Date("2006-12-31"), by = 1)) %>% 
  dplyr::left_join(., df1, by ="Date") %>% 
  tidyr::gather("id", "Sales", 2:9) 

UPDATE

I tried plotting the facets on many pages using ggforce::facet_wrap_paginate.

Parts of the code below was obtained from the ggforce manual (page 5) and this question.

n_pages_needed_df2 <- ceiling(
  length(levels(df2$id)) * length(levels(df2$id)) / 4
)


for (i in seq_len(n_pages_needed_df2)) {
  pl<-ggplot(df2, aes(x =Date, y = Sales , color = id))+ 
    geom_line(size = 0.2, alpha = 0.3)+
    scale_x_date(breaks = seq(as.Date("2001-01-01"),
                              as.Date("2007-01-01"), by="1 year"),
                 labels = date_format("%Y"))+
    facet_wrap_paginate(~id, ncol = 2, nrow = 2, page = i,
                        strip.position="top", scales="free_y")
  ggsave(paste("fig-", i, ".png", sep=""), height = 5.8, width = 10.04 , dpi = 600)
}

It worked fine and I got the following two .png plots (I preferred to save it as .png as it will be easier/faster to me to be imported into Microsoft Office).

first plot

second plot

However, it resulted in a third empty plot and these errors

Error in matrix(list(zeroGrob()), nrow = nrow, ncol = ncol) :
invalid 'nrow' value (too large or NA) In addition: Warning messages: 1: Removed 6681 rows containing missing values (geom_path). 2: Removed 6681 rows containing missing values (geom_path). 3: Removed 6681 rows containing missing values (geom_path). 4: In min(layout$ROW) : no non-missing arguments to min; returning Inf 5: In max(layout$COL) : no non-missing arguments to max; returning -Inf 6: In max(layout$ROW) : no non-missing arguments to max; returning -Inf 7: In matrix(list(zeroGrob()), nrow = nrow, ncol = ncol) : NAs introduced by coercion to integer range

Any suggestions how I fix these errors?

Answer 1

Removing the NAs works well:

library(ggplus)
df2 <- df2[!is.na(df2$Sales),]
pdf("C:\1\test.pdf", 7, 5)
p <- ggplot(df2, aes(x =Date, y = Sales)) +
  geom_line(aes(colour=id),size = 0.01)+
  scale_x_date(breaks = seq(as.Date("2001-01-01"),
                            as.Date("2007-01-01"), by="1 year"),
               labels = date_format("%Y"))
facet_multiple(plot = p, facets = 'id', ncol = 2, nrow = 2)
dev.off()

PS: Another option is using the gridExtra package.