我经常想显示给定基准年的变化。例如,自给定年份以来,发生了什么变化(百分比)? gapminder
数据集提供了一个很好的示例:
要开始获得答案,您需要group_by
年和大洲,然后summarize
求和。但是,您如何获得一个汇总值,即1952年人口呢?
library(gapminder)
gapminder %>%
group_by(year, continent) %>%
summarize(tot_pop = sum(as.numeric(pop)),
SUMMARY_VAL = POP_SUM_1952,
CHG_SINCE_1952 = (tot_pop - SUMMARY_VAL ) / SUMMARY_VAL ) %>%
ggplot(aes(x = year, y = CHG_SINCE_1952, color = continent)) +
geom_line()
仅供参考,gapminder看起来像这样:
# A tibble: 1,704 x 6
country continent year lifeExp pop gdpPercap
<fct> <fct> <int> <dbl> <int> <dbl>
1 Afghanistan Asia 1952 28.8 8425333 779.
2 Afghanistan Asia 1957 30.3 9240934 821.
3 Afghanistan Asia 1962 32.0 10267083 853.
4 Afghanistan Asia 1967 34.0 11537966 836.
5 Afghanistan Asia 1972 36.1 13079460 740.
6 Afghanistan Asia 1977 38.4 14880372 786.
7 Afghanistan Asia 1982 39.9 12881816 978.
8 Afghanistan Asia 1987 40.8 13867957 852.
9 Afghanistan Asia 1992 41.7 16317921 649.
10 Afghanistan Asia 1997 41.8 22227415 635.
# ... with 1,694 more rows
答案 0 :(得分:2)
我正在尝试提出一个一步的解决方案。同时,这是一个简单的两步解决方案-
pop_1952 <- filter(gapminder, year == 1952) %>%
group_by(continent) %>%
summarise(tot_pop_1952 = sum(pop, na.rm = T))
gapminder %>%
group_by(year, continent) %>%
summarize(tot_pop = sum(as.numeric(pop))) %>%
left_join(pop_1952, by = "continent") %>%
mutate(
CHG_SINCE_1952 = (tot_pop - tot_pop_1952) / tot_pop_1952
) %>%
ggplot(aes(x = year, y = CHG_SINCE_1952, color = continent)) +
geom_line()
如果有帮助的话,这里是一个解决方案(我认为从技术上讲还是两个步骤)-
gapminder %>%
mutate(
tot_pop_1952 = ave(as.numeric(pop)*(year == 1952), continent, FUN = sum)
) %>%
group_by(year, continent) %>%
summarize(
tot_pop = sum(as.numeric(pop)),
tot_pop_1952 = mean(tot_pop_1952),
CHG_SINCE_1952 = (tot_pop - tot_pop_1952) / tot_pop_1952
) %>%
ggplot(aes(x = year, y = CHG_SINCE_1952, color = continent)) +
geom_line()
答案 1 :(得分:0)