compute_count {ggvis} | R Documentation |
Count data at each location
compute_count(x, x_var, w_var = NULL)
x |
Dataset-like object to count. Built-in methods for data frames, grouped data frames and ggvis visualisations. |
x_var,w_var |
Names of x and weight variables. |
A data frame with columns:
count_ |
the number of points |
x_ |
the x value where the count was made |
The width of each "bin" is set to the resolution of the data – that is, the smallest difference between two x values.
compute_bin
For counting cases within ranges of
a continuous variable.
compute_align
For calculating the "width" of data.
mtcars %>% compute_count(~cyl) # Weight the counts by car weight value mtcars %>% compute_count(~cyl, ~wt) # If there's one weight value at each x, it effectively just renames columns. pressure %>% compute_count(~temperature, ~pressure) # Also get the width of each bin pressure %>% compute_count(~temperature, ~pressure) %>% compute_align(~x_) # It doesn't matter whether you transform inside or outside of a vis mtcars %>% compute_count(~cyl, ~wt) %>% compute_align(~x_) %>% ggvis(x = ~xmin_, x2 = ~xmax_, y = ~count_, y2 = 0) %>% layer_rects() mtcars %>% ggvis(x = ~xmin_, x2 = ~xmax_, y = ~count_, y2 = 0) %>% compute_count(~cyl, ~wt) %>% compute_align(~x_) %>% layer_rects()