How do you modify numerical values from a column when using tidyverse pivot

I need to plot the following with B variable values multiplied by 10, in order to be adjusted to the secondary axis. How do you do this in tidyverse? I am using mutate within the %>% but does not work

    data<- data.frame(
          Date=(1:13),
          A=c(1.12,2.78,2.08,1.55,0.67,0.98,1.43,0.42,0.30,0.82,0.51,0.23,0.44),
          B= c(0.10,0.07,0.04,0.05,0.10,0.08,0.12,0.05,0.02,0.11,0.06,0.05,0.11),
          C= c(9.97,6.94,10.87,9.69,12.27,11.27,10.42,10.97,9.15,10.59,11.64,8.86,8.47))
    
        library(tidyverse)
data %>%
  select(-C) %>%
  pivot_longer(cols = -Date) %>%
  # mutate(data, B2= B*10) %>% THIS IS WHAT I AM TRYING AND DOES NOT WORK, B VALUE STO BE MULTIPLIED BY 10
  ggplot(aes(Date, value, linetype = name))    
  geom_line()  
  geom_point()   
  scale_y_continuous(sec.axis = sec_axis(~./100, name= expression(paste("B", "(", mu, "M)"))))   
  scale_linetype_manual(values= LINES)  
  # scale_color_manual(name = "", values = c("A" = "black", "B" = "black")) 
  theme_classic() 
  ylab(bquote(A ~ (mu~M))) 
  xlab("")

CodePudding user response：

If I understand correctly you want to multiply by 10 in instances where name == "B". If this is the case this works using tidyverse:

data %>%
  select(-C) %>%
  pivot_longer(cols = -Date) %>% 
  mutate(value = case_when(name == "B" ~ value * 10, TRUE ~ value))

CodePudding user response：

Another option is to use ifelse inside aes

data %>%
  select(-C) %>%
  pivot_longer(cols = -Date) %>%
  ggplot(aes(Date, ifelse(name == "B", 10 * value, value), linetype = name))    
  geom_line()  
  geom_point()   
  scale_y_continuous(sec.axis = sec_axis(~./100, 
          name= expression(paste("B", "(", mu, "M)"))))   
  scale_linetype_manual(values = 1:2)  
  theme_classic(base_size = 16)  
  ylab(bquote(A ~ (mu~M)))  
  xlab("")