The final goal is to make two lines and find the intersection point.
I don't want to argue more about the reason.
The tol suggestion is reasonable, and I'll take that.
2019/4/19 4:12, Jeff Newmiller:
The fact that you think x~y is interchangeable with y~x suggests to me that you
will have a
gt; Wang
> Sent: Thursday, April 18, 2019 12:36 PM
> To: Michael Dewey ; r-help@r-project.org
> Subject: Re: [R] lm fails on some large input
>
> I just want to make a line out of timestamps vs some coordinates, so y~x or
> x~y doesn't matter.
>
> Yes, I know the answer. Wh
The fact that you think x~y is interchangeable with y~x suggests to me that you
will have a difficult time convincing R Core that this is a bug. I recommend
that you take at leastan upper division college course in linear regression
first.
On April 18, 2019 9:35:55 AM PDT, Dingyuan Wang
I just want to make a line out of timestamps vs some coordinates, so y~x
or x~y doesn't matter.
Yes, I know the answer. When trying R, I'm surprised that R can't solve
that either. I first noticed that PostgreSQL can't solve it, and found
that they fixed that in pg 12.
I make a general rule not to stick time values into numerical analysis
algorithms without first subtracting a reasonable epoch (to obtain difftime)
and then using as.numeric.POSIXt with the units argument set explicitly so the
analysis uses numeric values that I can interpret. While the
Dear Peter,
> -Original Message-
> From: peter dalgaard [mailto:pda...@gmail.com]
> Sent: Thursday, April 18, 2019 12:23 PM
> To: Fox, John
> Cc: Michael Dewey ; Dingyuan Wang
> ; r-help@r-project.org
> Subject: Re: [R] lm fails on some large input
>
> Um,
> On Apr 18, 2019, at 8:24 AM, Michael Dewey wrote:
>
> Perhaps subtract 1506705766 from y?
Good advice. Some further notes follow.
One can specify `tol` to have a smaller than default value
e.g.
m2 <- lm(x ~ y, tol=1e-12)
which is accurate:
plot(y,x)
abline(coef=coef(m2))
Users
This sort of data arises quite easily if you deal with time/dates around
now. E.g.,
> d <- data.frame(
+ when = seq(as.POSIXct("2017-09-29 18:22:01"), by="secs", len=10),
+ measurement = log2(1:10))
> coef(lm(data=d, measurement ~ when))
(Intercept) when
d Dingyuan Wang,
>
>> -Original Message-
>> From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of Michael
>> Dewey
>> Sent: Thursday, April 18, 2019 11:25 AM
>> To: Dingyuan Wang ; r-help@r-project.org
>> Subject: Re: [R] lm fails on some large inp
Dear Michael and Dingyuan Wang,
> -Original Message-
> From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of Michael
> Dewey
> Sent: Thursday, April 18, 2019 11:25 AM
> To: Dingyuan Wang ; r-help@r-project.org
> Subject: Re: [R] lm fails on some large input
>
Perhaps subtract 1506705766 from y?
Saying some other software does it well implies you know what the
_correct_ answer is here but I would question what that means with this
sort of data-set.
On 17/04/2019 07:26, Dingyuan Wang wrote:
Hi,
This input doesn't have any interesting properties
Hi,
This input doesn't have any interesting properties except y is unix
time. Spreadsheets can do this well.
Is this a bug that lm can't do x ~ y?
R version 3.5.2 (2018-12-20) -- "Eggshell Igloo"
Copyright (C) 2018 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu
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