R Multiple Lines on a Chart

Question

I am trying to place 3 columns onto a line chart. But while I can create the chart the lines are not being drawn correctly.

Below are some data and the two different ways I've tried to create the charts.

any help is great;y appreciated.

Data:

structure(list(Year = c("2017-08", "2017-09", "2017-10", "2017-11", 
"2017-12", "2018-01", "2018-02", "2018-03", "2018-04", "2018-05", 
"2018-06", "2018-07", "2018-08", "2018-09", "2018-10", "2018-11", 
"2018-12", "2019-01", "2019-02", "2019-03", "2019-04", "2019-05", 
"2019-06", "2019-07", "2019-08", "2019-09", "2019-10", "2019-11", 
"2019-12", "2020-01", "2020-02", "2020-03", "2020-04", "2020-05", 
"2020-06", "2020-07", "2020-08"), Order.Comment.1 = structure(c(2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L), .Label = c("", "BR", "BST", "CG", "CN", "CT", 
"DM", "DR", "EM", "EMR", "EMURG", "ENDOC", "EYE", "FF", "GI", 
"GYN", "GYNAE", "HAEM", "HN", "ICC", "LBX", "LYMPH", "MN", "MOHS", 
"NEUR", "NEURO", "NO REPORT ISSUED", "PAED", "PAEDGI", "PERI", 
"PG", "RE", "SK", "TEST PATIENT", "UGI", "UR", "URGI"), class = "factor"), 
    P.Less.3 = c(50.8250825082508, 53.7906137184115, 54.8172757475083, 
    47.6190476190476, 51.8939393939394, 56.508875739645, 52.2900763358779, 
    49.3421052631579, 43.3447098976109, 50.4918032786885, 50.1501501501502, 
    49.7206703910614, 47.5409836065574, 46.0264900662252, 45.6896551724138, 
    47.2312703583062, 44.3965517241379, 57.8313253012048, 49.8098859315589, 
    48.6013986013986, 49.0566037735849, 45.3531598513011, 49.063670411985, 
    53.8961038961039, 50, 43.5810810810811, 45, 47.3509933774834, 
    43.4782608695652, 39.041095890411, 36.9649805447471, 43.2515337423313, 
    39.5522388059701, 54.6875, 46.2765957446808, 36.1990950226244, 
    40.7216494845361), P.Less.7 = c(87.7887788778878, 89.1696750902527, 
    89.0365448504983, 88.8888888888889, 87.8787878787879, 92.603550295858, 
    89.6946564885496, 87.8289473684211, 84.641638225256, 83.6065573770492, 
    83.1831831831832, 87.1508379888268, 89.0710382513661, 79.8013245033112, 
    79.3103448275862, 83.3876221498371, 81.0344827586207, 87.9518072289157, 
    82.8897338403042, 87.0629370629371, 81.8867924528302, 86.2453531598513, 
    82.7715355805243, 88.961038961039, 87.1428571428571, 83.7837837837838, 
    83.8888888888889, 84.1059602649007, 78.9855072463768, 84.5890410958904, 
    84.4357976653696, 84.6625766871166, 84.3283582089552, 91.40625, 
    79.7872340425532, 76.9230769230769, 72.680412371134), P.Less.10 = c(97.3597359735974, 
    97.4729241877256, 99.3355481727575, 98.4126984126984, 96.2121212121212, 
    98.5207100591716, 97.3282442748092, 97.3684210526316, 96.5870307167236, 
    94.0983606557377, 96.0960960960961, 96.3687150837989, 96.9945355191257, 
    92.3841059602649, 92.2413793103448, 95.4397394136808, 93.5344827586207, 
    95.1807228915663, 95.0570342205323, 97.9020979020979, 94.7169811320755, 
    95.1672862453532, 94.0074906367041, 95.7792207792208, 96.4285714285714, 
    95.6081081081081, 94.7222222222222, 95.364238410596, 93.8405797101449, 
    95.8904109589041, 95.7198443579767, 96.9325153374233, 94.7761194029851, 
    96.875, 95.2127659574468, 92.3076923076923, 85.0515463917526
    )), row.names = c(NA, 37L), class = "data.frame")

Way 1:

ggplot(Mth_TaT_Data, aes(x=Year, group = "BR")) + 
  geom_line(aes(y = P.Less.3), color = "darkred") + 
  geom_line(aes(y = P.Less.7), color="steelblue", linetype="twodash")+ 
  geom_line(aes(y = P.Less.10), color="sienna1", linetype="dashed")+
  ggtitle("Test")+
  theme(axis.text.x = element_text(angle=45, hjust = 1))

Way 2:

df <- Mth_TaT_Data %>%
  select(Year, Order.Comment.1,P.Less.3, P.Less.7, P.Less.10) %>%
  gather(key = "variable", value = "value", -Year, -Order.Comment.1)

ggplot(df, aes(x = Year, y = value,group = "BR")) + 
  geom_line(aes(color = variable))+
ggtitle("Test")+
  theme(axis.text.x = element_text(angle=45, hjust = 1))

Answer 1

Following the comments of our valious colleages, it is bizarre what you want. If you want one line per column the strategy you followed in the first plot might be right. Maybe you want to see each line in a legend, so an approach reshaping data with tidyverse would work. Here the code:

library(tidyverse)
#Code
Mth_TaT_Data %>%
  pivot_longer(-c(1,2)) %>%
  mutate(name=factor(name,levels=unique(name),ordered = T)) %>%
  ggplot(aes(x=Year, y=value,group = name,color=name,linetype=name)) + 
  geom_line()+
  scale_color_manual(values=c("darkred","steelblue","sienna1"))+
  scale_linetype_manual(values = c("solid","twodash","dashed"))+
  ggtitle("Test")+
  theme(axis.text.x = element_text(angle=45, hjust = 1))+
  labs(color='Column',linetype='Column')

Output:

Answer 2

This type of problems generally has to do with reshaping the data. The format should be the long format and the data is in wide format, like the question itself shows the OP is trying to do in way 2 . See also this post on how to reshape the data from wide to long format.

In the code below I first create three vectors:

1. lvls is a vector of the column names that start with "P" , to be used as the levels of the long format column variable and as the names of the two other vectors that are created;
2. linetp is a named vector of line types;
3. colr is a named vector of (line) colors.

And the final code is therefore a bit longer than the question's.

library(dplyr)
library(tidyr)
library(ggplot2)

lvls <- grep("^P", names(Mth_TaT_Data), value = TRUE)
linetp <- setNames(c("solid", "twodash", "dashed"), lvls)
colr <- setNames(c("darkred", "steelblue", "sienna1"), lvls)


Mth_TaT_Data %>%
  mutate(Year = paste(Year, "01", sep = "-"),
         Year = zoo::as.yearmon(Year)) %>%
  pivot_longer(
    cols = starts_with('P'),
    names_to = 'variable',
    values_to = 'value'
  ) %>%
  mutate(variable = factor(variable, levels = lvls)) %>%
  ggplot(aes(x = Year, y = value)) + 
  geom_line(aes(linetype = variable, color = variable)) +
  ggtitle("Test") +
  scale_color_manual(values = colr) +
  scale_linetype_manual(values = linetp) +
  theme(axis.text.x = element_text(angle = 45, hjust = 1))