如何在 R 中将字符串双精度转换为数字双精度？

Question

I have string "178960.02" that should be converted into numeric with floating-point.

This generates only integer value "178960" without ".02".

How to have double value with floating part

as.numeric("178960.02")
as.double("178960.02")

Thanks!

Answer 1

Try this:

#Code
options(digits=9)
as.numeric("178960.02")

Output:

[1] 178960.02

Answer 2

I wondered if the questioner was under the impression that the implicit print of the R REPL (read-eval-print loop) was actually showing the correct value of a double? (And it appears my worries were well-placed.)

x <- as.numeric("178960.02")

 sprintf("%s", x)
#[1] "178960.02"

print(x, digits = 12)
#[1] 178960.02

The decimal fraction was always there, just not being displayed. It would not necessarily need to have the global options changed to see the more "complete" value. Other options can be set in print arguments.

To see that it was always there it is easy to multiply by 100:

x*100
#[1] 17896002