去除极坐标图边缘的额外空间和环

Question

我有一个极地情节,ggplot2因为我在完成(相当简单的情节)时非常接近.我已经能够帮助移除矩形边界,但是我不需要移除最后一个范围轮廓和具有方位标签的绘图周围环之间的额外空间.我希望这个情节的界限是15,000 ......而不是15,214(我把这个数字提高了).谢谢你的帮助.

生成图的代码如下:

# Load needed Libraries ---------------------------------------------------

library(ggplot2)

# Generate Fake Data ------------------------------------------------------

N    = 25
bng  = runif(N, min =  0, max = 360)
rng  = rlnorm(N, meanlog = 9, sdlog = 1)
det  = runif(N, min = 0, max = 1) >= 0.5

det  = factor(det)

data = data.frame(bng, rng, det)

# Generate the Plot -------------------------------------------------------

plot = ggplot(data) + theme_bw() +
  geom_point(aes(x = bng, y = rng, color = det), size = 5, alpha = 0.7) +
  scale_x_continuous(limits = c(0,360), expand = c(0,0), breaks = seq(0,360-1, by=45)) +
  scale_y_continuous(limits = c(0,15000), breaks = seq(0,15000, by = 3000)) +
  coord_polar(theta = 'x', start = 0, direction = 1) +
  theme(legend.key = element_blank()) +
  theme(panel.border = element_blank(), axis.ticks = element_blank(), axis.text.y = element_blank()) +
  labs(x = '', y = '') +
  scale_color_manual(name = '', values = c('red', 'black'), breaks = c(FALSE, TRUE), labels = c('Not Detected', 'Detected'))
plot

Answer 1

额外的空间由a的最外圈产生panel.grid.默认情况下会在theme您使用过的网格中添加网格(以及大多数其他ggplot主题; 此处为默认设置)

因此,除去panel.grid在theme.然后你可以根据品味创建一个自己的网格,使用eg geom_hline和geom_vline.在这里,我使用了你指定的休息scale_x和_y拦截.我挑线的颜色和大小从默认panel.grid.major在theme_bw.

ggplot(data = df) +
  geom_point(aes(x = bng, y = rng, color = det), size = 5, alpha = 0.7) +
  geom_hline(yintercept = seq(0, 15000, by = 3000), colour = "grey90", size = 0.2) +
  geom_vline(xintercept = seq(0, 360-1, by = 45), colour = "grey90", size = 0.2) +
  coord_polar(theta = 'x', start = 0, direction = 1) +
  labs(x = '', y = '') +
  scale_color_manual(name = '',
                     values = c('red', 'black'),
                     breaks = c(FALSE, TRUE),
                     labels = c('Not Detected', 'Detected')) +
  scale_x_continuous(limits = c(0, 360), expand = c(0, 0), breaks = seq(0, 360-1, by = 45)) +
  scale_y_continuous(limits = c(0, 15000), breaks = seq(0, 15000, by = 3000)) +
  theme_bw() +
  theme(panel.border = element_blank(),
        legend.key = element_blank(),
        axis.ticks = element_blank(),
        axis.text.y = element_blank(),
        panel.grid  = element_blank())