Update README.md

README.md

@@ -1,6 +1,6 @@
 # ggvenn
 
-Venn Diagram by ggplot2. This package is inspired by [Venny](http://bioinfogp.cnb.csic.es/tools/venny/index.html)
+Venn Diagram by ggplot2, with really easy-to-use API. This package is inspired by [Venny](http://bioinfogp.cnb.csic.es/tools/venny/index.html)
 
 ## Installation
 
@@ -9,46 +9,133 @@ if (!require(devtools)) install.packages("devtools")
 devtools::install_github("yanlinlin82/ggvenn")
 ```
 
-## Usage Example
+## Quick Start
+
+This package supports both `list` and `data.frame` type data as input.
+
+For `list` data (each element is a set):
 
 ```{r}
 library(ggvenn)
 
-# use list as input
 a <- list(`Set 1` = c(1, 3, 5, 7, 9),
           `Set 2` = c(1, 5, 9, 13),
           `Set 3` = c(1, 2, 8, 9),
           `Set 4` = c(6, 7, 10, 12))
-ggvenn(a, c("Set 1", "Set 2"))
-ggvenn(a, c("Set 1", "Set 2", "Set 3"))
-ggvenn(a)
+ggvenn(a, c("Set 1", "Set 2"))            # draw two-set venn
+ggvenn(a, c("Set 1", "Set 2", "Set 3"))   # draw three-set venn
+ggvenn(a)   # without set names, the first 4 elements in list will be chose to draw four-set venn
+```
 
-# use data.frame as input
+For `data.frame` data (each logical column is a set):
+
+```{r}
 d <- tibble(value   = c(1, 2, 3, 5, 6, 7, 8, 9, 10, 12, 13),
             `Set 1` = c(T, F, T, T, F, T, F, T, F,  F,  F),
             `Set 2` = c(T, F, F, T, F, F, F, T, F,  F,  T),
             `Set 3` = c(T, T, F, F, F, F, T, T, F,  F,  F),
             `Set 4` = c(F, F, F, F, T, T, F, F, T,  T,  F))
-ggvenn(d, c("Set 1", "Set 2"))
-ggvenn(d, c("Set 1", "Set 2", "Set 3"))
-ggvenn(d)
-
-# ggplot gramma
-d %>% ggvenn(aes(A = `Set 1`, B = `Set 2`))
-d %>% ggvenn(aes(A = `Set 1`, B = `Set 2`, C = `Set 3`))
-d %>% ggvenn(aes(A = `Set 1`, B = `Set 2`, C = `Set 3`, D = `Set 4`))
+ggvenn(d, c("Set 1", "Set 2"))           # draw two-set venn
+ggvenn(d, c("Set 1", "Set 2", "Set 3"))  # draw three-set venn
+ggvenn(d)   # without set names, the first 4 logical column in data.frame will be chose to draw four-set venn
+```
+
+For `data.frame` data, there is also another way to plot in ggplot gramma:
+
+```{r}
+# draw two-set venn (use A, B in aes)
+ggplot(d, aes(A = `Set 1`, B = `Set 2`)) +
+  geom_venn() + theme_void() + coord_fixed()
+
+# draw three-set venn (use A, B, C in aes)
+ggplot(d, aes(A = `Set 1`, B = `Set 2`, C = `Set 3`)) +
+  geom_venn() + theme_void() + coord_fixed()
+
+# draw four-set venn (use A, B, C, D in aes)
+ggplot(d, aes(A = `Set 1`, B = `Set 2`, C = `Set 3`, D = `Set 4`)) +
+  geom_venn() + theme_void() + coord_fixed()
 ```
 
 ## Screenshots
 
-<p align="center">
-  <img width="400" height="400" src="plots/venn-2.svg" alt="Venn 2">
-</p>
+<table><tr>
+<td><img width="400" height="400" src="plots/venn-2.svg" alt="Venn 2"></td>
+<td><img width="400" height="400" src="plots/venn-3.svg" alt="Venn 3"></td>
+<td><img width="400" height="400" src="plots/venn-4.svg" alt="Venn 4"></td>
+</tr></table>
+
+## More Options
+
+There are more options for customizing the venn diagram.
+
+1. Tune the color and size
+
+    For filling:
+
+    * `fill_color` - default is c("blue", "yellow", "green", "red")
+    * `fill_alpha` - default is 0.5
+
+    For stroke:
+
+    * `stroke_color` - default is "black"
+    * `stroke_alpha` - default is 1
+    * `stroke_alpha` - default is 1
+    * `stroke_linetype` - default is "solid"
+
+    For set name:
+
+    * `set_name_color` - default is "black"
+    * `set_name_size` - default is 6
+
+    For text:
+
+    * `text_color` - default is "black"
+    * `text_size` - default is 4
+
+    All parameters above could be used in both `ggvenn()` and `geom_venn()`.
+
+    For example:
+
+    ```{r}
+    a <- list(A = 1:4, B = c(1,3,5))
+    ggvenn(a, stroke_linetype = 2, stroke_size = 0.5,
+      set_name_color = "red", set_name_size = 15,
+      fill_color = c("pink", "gold"))
+    ```
+
+2. Show elements
+
+    * `show_elements` - default is FALSE
+    * `label_sep` - text used to concatenate elements, default is ","
+    
+    For example:
+    
+    ```{r}
+    a <- list(A = c("apple", "pear", "peach"),
+              B = c("apple", "lemon"))
+    ggvenn(a, show_elements = TRUE)
+    
+    ggvenn(a, show_elements = TRUE, label_sep = "\n")  # show elements in line
+    ```
+
+3. Hide percentage
+
+    * `show_percentage` - default is TRUE
+
+    For example:
+    
+    ```{r}
+    a <- list(A = 1:5, B = 1:2)
+    ggvenn(a, show_percentage = FALSE)
+    ```
+
+4. Change digits of percentage
 
-<p align="center">
-  <img width="400" height="400" src="plots/venn-3.svg" alt="Venn 3">
-</p>
+    * `digits` - default is 1
 
-<p align="center">
-  <img width="400" height="400" src="plots/venn-4.svg" alt="Venn 4">
-</p>
+    For example:
+    
+    ```{r}
+    a <- list(A = 1:5, B = 1:2)
+    ggvenn(a, digits = 2)
+    ```