使用指标功能查找总和？

Question

X=c(5.3552,5.0212,11.1375,10.6883,0.0000,1.4795,0.0000,0.0000,0.8646,8.5751,4.8460,1.3602,20.3108,0.0000,20.883,0.000,0.000,11.3210,7.707,0.000)
Y=c(2.746,2.776,2.785,2.788,2.777,2.778,2.777,-2.0798,2.546,-1.3201,0.905,2.777,-11.7463,-0.2909,-0.2417,0.1206,2.7777,2.3524,1.7479,1.5524)

我将指标函数Z定义为：当X> 0时Z取1，当X = 0时取Z。 在这里，我无法为以下表达式

编写R代码

(Z-1)*X+Z*Y

请帮助我解决这个问题。 谢谢。

Answer 1

这个怎么样？

Z = rep(0, length(X))
Z[X>0] = 1
Z
#[1] 1 1 1 1 0 1 0 0 1 1 1 1 1 0 1 0 0 1 1 0
(Z-1)*X+Z*Y
#[1]   2.7460   2.7760   2.7850   2.7880   0.0000   2.7780   0.0000   0.0000   2.5460  -1.3201   0.9050   2.7770 -11.7463   0.0000  -0.2417   0.0000   0.0000
#[18]   2.3524   1.7479   0.0000

Answer 2

您可以使用ifelse函数定义指标函数Z，其中Z在X> 0时取1并在X = 0时取0。

Z <- ifelse(X>0 , 1 , 0)

(Z-1)*X+Z*Y

[1]   2.7460   2.7760   2.7850   2.7880   0.0000   2.7780   0.0000   0.0000   2.5460  -1.3201   0.9050   2.7770 -11.7463   0.0000  -0.2417
[16]   0.0000   0.0000   2.3524   1.7479   0.0000