visualize numerical strings as a matrixed heatmap

Question

I'm trying to visualize a matrix of numerical strings, as a heatmap Take this example, of 36 element length "History" numerical strings, and, say I have 6 rows (i actually have 500 rows). I want to visualize a heat map of a matrix of 6x36 "pixels or cells". Additionally it would be great to sort or split them visually by True/False on the "Survive" variable.

    testdata=                   
       History                                Survive
    1  111111111111111211111111111111111111   FALSE
    2  111111111111111110000000000000000000   TRUE
    3  000111222111111111111111111111110000   FALSE
    4  111111111111111111111111100000000000   TRUE
    5  011231111111111111111111111111111111   FALSE
    6  111111234111111111111111110000000000   TRUE

Have you checked out [this post](https://stackoverflow.com/questions/2076370/most-underused-data-visualization)? You can `facet_wrap` by your `Survive` variable. — kstew, Aug 15 '19 at 18:53
yea, very familiar with facet_wrap, but the string to matrix to heatmap grid is what i'm confused about. I'll check out the post further you referenced. — nerdlyfe, Aug 15 '19 at 19:44

score 2 · Accepted Answer · answered Aug 15 '19 at 22:19

Here is one idea. We can split the Histroy column and then created rowid and ID column to plot the data as a heatmap.

library(tidyverse)

testdata2 <- testdata %>% mutate(History = str_split(History, pattern = "")) 

testdata3 <- testdata2%>%
  rowid_to_column() %>%
  unnest() %>%
  group_by(rowid) %>%
  mutate(ID =row_number()) 

p <- ggplot(testdata3, aes(x = ID, y = rowid, fill = History)) +
  geom_tile(color = "black") +
  scale_fill_brewer() +
  scale_y_reverse() +
  labs(x = "", y = "") +
  theme_minimal()

print(p)

If we want to plot the data as facets by TRUE and FALSE in the Survival column, we need to create the rowid separately as TRUE and FALSE for Survival.

testdata4 <- testdata2%>%
  group_by(Survive) %>%
  mutate(rowid = row_number()) %>%
  unnest() %>%
  group_by(Survive, rowid) %>%
  mutate(ID = row_number()) 

p2 <- ggplot(testdata4, aes(x = ID, y = rowid, fill = History)) +
  geom_tile(color = "black") +
  scale_fill_brewer() +
  scale_y_reverse() +
  labs(x = "", y = "") +
  theme_minimal() +
  facet_grid(~ Survive)

print(p2)

Data

testdata <- read.table(text =                    
    "  History                                Survive
    1  111111111111111211111111111111111111   FALSE
    2  111111111111111110000000000000000000   TRUE
    3  000111222111111111111111111111110000   FALSE
    4  111111111111111111111111100000000000   TRUE
    5  011231111111111111111111111111111111   FALSE
    6  111111234111111111111111110000000000   TRUE",
    header = TRUE, stringsAsFactors = FALSE,
    colClasses = c("numeric", "character", "logical"))

visualize numerical strings as a matrixed heatmap

1 Answers1