ggplot2:在自变量上绘制积分的简单方法? [英] ggplot2: easy way to plot integral over independent variable?

问题描述

我正在集成函数 f(t)= 2t (仅作为示例)，并希望使用作为时间 t 的函数来绘制积分.>

I'm integrating a function f(t) = 2t (just an example) and would like to plot the integral as a function of time t using

awesome_thing <- function(t) {2*t}
integrate(awesome_thing, lower=0, upper=10)

但是，我想在ggplot2中将积分绘制为时间的函数，因此在此示例中，绘制的点将是(1,1)，(2,4)，(3,9)，...，(10,100).

However, I would like to plot the integral as a function of time in ggplot2, so for this example the plotted points would be (1,1), (2,4), (3,9), ..., (10,100).

在ggplot中是否有一种简单的方法(例如，类似于如何绘制函数的图)?我知道我可以手动"评估和绘制每个 t 的数据，但是我想我可以看看是否有人可以推荐一种更简单的方法.

Is there an easy way to do this in ggplot (e.g., something similar to how functions are plotted)? I understand I can "manually" evaluate and plot the data for each t, but I thought i'd see if anyone could recommend a simpler way.

推荐答案

这是 ggplot 解决方案和 stat_function

 # create a function that is vectorized over the "upper" limit of your
 # integral
int_f <- Vectorize(function(f = awesome_thing, lower=0,upper,...){
    integrate(f,lower,upper,...)[['value']] },'upper')


ggplot(data.frame(x = c(0,10)),aes(x=x)) + 
   stat_function(fun = int_f, args = list(f = awesome_thing, lower=0))

这篇关于ggplot2:在自变量上绘制积分的简单方法?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！