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PIKAL Petr

2019-Jan-17 14:30 UTC

[R] I can't get seq to behave how I think it should

Hi

It is not seq problem, it is floating point numbers representation in finit
precision problem. Ben pointed to it and you could learn about it from FAQ 7.31.

Cheers
Petr
> -----Original Message-----
> From: POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS
> FOUNDATION TRUST) <calum.polwart at nhs.net>
> Sent: Thursday, January 17, 2019 2:56 PM
> To: PIKAL Petr <petr.pikal at precheza.cz>; Ben Tupper <btupper at
bigelow.org>
> Cc: r-help at r-project.org
> Subject: RE: [R] I can't get seq to behave how I think it should
>
> Thanks guys.
>
> I've used Petr's method and its working for me.
>
> If the data had been from a calculation I'd have rounded it... just
didn't expect
> seq to break it!
>
> C
>
> -----Original Message-----
> From: PIKAL Petr [mailto:petr.pikal at precheza.cz]
> Sent: 17 January 2019 13:53
> To: Ben Tupper; POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS
> FOUNDATION TRUST)
> Cc: r-help at r-project.org
> Subject: RE: [R] I can't get seq to behave how I think it should
>
> Hi
>
> Or you could use rounding.
> which(round(lut, 3)==1.8)
> [1] 401
>
> Cheers
> Petr
>
> > -----Original Message-----
> > From: R-help <r-help-bounces at r-project.org> On Behalf Of Ben
Tupper
> > Sent: Thursday, January 17, 2019 2:43 PM
> > To: POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS
> FOUNDATION TRUST)
> > <calum.polwart at nhs.net>
> > Cc: r-help at r-project.org
> > Subject: Re: [R] I can't get seq to behave how I think it should
> >
> > Hi,
> >
> > This looks like a floating point reality bump - see
> >
> > https://cran.r-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-think-
> > these-numbers-are-equal_003f <https://cran.r-project.org/doc/FAQ/R-
> > FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f>
> >
> > You can use other methods to finding your row - I would opt for
> > findInterval()
> >
> > > lut = seq(1.4, 2.1, by=0.001)
> > > findInterval(1.8, lut)
> > [1] 401
> >
> > findInterval() uses a rapid search to find the index in the look up
> > table (lut) that is just less than  or equal to the search value (in
your example
> 1.8).
> >
> > Cheers,
> > Ben
> >
> > > On Jan 17, 2019, at 8:33 AM, POLWART, Calum (COUNTY DURHAM AND
> > DARLINGTON NHS FOUNDATION TRUST) via R-help <r-help at
r-project.org>
> > wrote:
> > >
> > > I am using seq with the expression seq(1.4, 2.1, by=0.001) to
create
> > > a sequence of references from 1.4 to 2.1 in 0.001 increments. 
They
> > > appear to be created correctly.  They have a related pair of data
> > > which for the purposes of this we will call val.  I'm
interested in
> > > the content on the row with seq = 1.8. But I can't seem to
get it
> > > returned.  I can get other values but not 1.8!  yet looking at
row
> > > 401 there is nothing to indicate an issue
> > >
> > >> a = 1.4
> > >> b = 2.1
> > >> seq = seq(a, b, by=0.001)
> > >> val = ceiling(seq * 50)
> > >> s=data.frame(seq, val)
> > >> s$val[seq==1.799]
> > > [1] 90
> > >> s$val[s$seq==1.8]
> > > numeric(0)
> > >> s$val[seq==1.8]
> > > numeric(0)
> > >> s$val[s$seq==1.800]
> > > numeric(0)
> > >> s$val[s$seq==1.801]
> > > [1] 91
> > >> head(s[s$seq>1.798,])
> > >      seq val
> > > 400 1.799  90
> > > 401 1.800  90
> > > 402 1.801  91
> > > 403 1.802  91
> > > 404 1.803  91
> > > 405 1.804  91
> > >
> > >
> > > Can anyone explain what's going on here and how I would
correctly
> > > find the
> > content of row 401 by using an expression to equal the seq column?
> > >
> > >
> > >
> > >
> > >
> > >
> >
> *******************************************************************
> > ***
> > > **********************************************
> > >
> > > This message may contain confidential information. If
> > > ...{{dropped:25}}
> >
> > ______________________________________________
> > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> > https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guide
> > http://www.R-project.org/posting-guide.html
> > and provide commented, minimal, self-contained, reproducible code.
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POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS FOUNDATION TRUST)

2019-Jan-17 14:56 UTC

head link

[R] I can't get seq to behave how I think it should

Well I get the issue with finite precision. As in SQRT(2) * SQRT(2) is not 2.

What surprised me was that seq(1.4, 2.1, by=0.001) starts at 1.3999999999999999
and not 1.4!


-----Original Message-----
From: PIKAL Petr [mailto:petr.pikal at precheza.cz]
Sent: 17 January 2019 14:30
To: POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS FOUNDATION TRUST); Ben
Tupper
Cc: r-help at r-project.org
Subject: RE: [R] I can't get seq to behave how I think it should

Hi

It is not seq problem, it is floating point numbers representation in finit
precision problem. Ben pointed to it and you could learn about it from FAQ 7.31.

Cheers
Petr
> -----Original Message-----
> From: POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS FOUNDATION
> TRUST) <calum.polwart at nhs.net>
> Sent: Thursday, January 17, 2019 2:56 PM
> To: PIKAL Petr <petr.pikal at precheza.cz>; Ben Tupper
> <btupper at bigelow.org>
> Cc: r-help at r-project.org
> Subject: RE: [R] I can't get seq to behave how I think it should
>
> Thanks guys.
>
> I've used Petr's method and its working for me.
>
> If the data had been from a calculation I'd have rounded it... just
> didn't expect seq to break it!
>
> C
>
> -----Original Message-----
> From: PIKAL Petr [mailto:petr.pikal at precheza.cz]
> Sent: 17 January 2019 13:53
> To: Ben Tupper; POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS
> FOUNDATION TRUST)
> Cc: r-help at r-project.org
> Subject: RE: [R] I can't get seq to behave how I think it should
>
> Hi
>
> Or you could use rounding.
> which(round(lut, 3)==1.8)
> [1] 401
>
> Cheers
> Petr
>
> > -----Original Message-----
> > From: R-help <r-help-bounces at r-project.org> On Behalf Of Ben
Tupper
> > Sent: Thursday, January 17, 2019 2:43 PM
> > To: POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS
> FOUNDATION TRUST)
> > <calum.polwart at nhs.net>
> > Cc: r-help at r-project.org
> > Subject: Re: [R] I can't get seq to behave how I think it should
> >
> > Hi,
> >
> > This looks like a floating point reality bump - see
> >
> > https://cran.r-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-thin
> > k- these-numbers-are-equal_003f
> > <https://cran.r-project.org/doc/FAQ/R-
> > FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f>
> >
> > You can use other methods to finding your row - I would opt for
> > findInterval()
> >
> > > lut = seq(1.4, 2.1, by=0.001)
> > > findInterval(1.8, lut)
> > [1] 401
> >
> > findInterval() uses a rapid search to find the index in the look up
> > table (lut) that is just less than  or equal to the search value (in
> > your example
> 1.8).
> >
> > Cheers,
> > Ben
> >
> > > On Jan 17, 2019, at 8:33 AM, POLWART, Calum (COUNTY DURHAM AND
> > DARLINGTON NHS FOUNDATION TRUST) via R-help <r-help at
r-project.org>
> > wrote:
> > >
> > > I am using seq with the expression seq(1.4, 2.1, by=0.001) to
> > > create a sequence of references from 1.4 to 2.1 in 0.001
> > > increments.  They appear to be created correctly.  They have a
> > > related pair of data which for the purposes of this we will call
> > > val.  I'm interested in the content on the row with seq =
1.8. But
> > > I can't seem to get it returned.  I can get other values but
not
> > > 1.8!  yet looking at row
> > > 401 there is nothing to indicate an issue
> > >
> > >> a = 1.4
> > >> b = 2.1
> > >> seq = seq(a, b, by=0.001)
> > >> val = ceiling(seq * 50)
> > >> s=data.frame(seq, val)
> > >> s$val[seq==1.799]
> > > [1] 90
> > >> s$val[s$seq==1.8]
> > > numeric(0)
> > >> s$val[seq==1.8]
> > > numeric(0)
> > >> s$val[s$seq==1.800]
> > > numeric(0)
> > >> s$val[s$seq==1.801]
> > > [1] 91
> > >> head(s[s$seq>1.798,])
> > >      seq val
> > > 400 1.799  90
> > > 401 1.800  90
> > > 402 1.801  91
> > > 403 1.802  91
> > > 404 1.803  91
> > > 405 1.804  91
> > >
> > >
> > > Can anyone explain what's going on here and how I would
correctly
> > > find the
> > content of row 401 by using an expression to equal the seq column?
> > >
> > >
> > >
> > >
> > >
> > >
> >
> *******************************************************************
> > ***
> > > **********************************************
> > >
> > > This message may contain confidential information. If
> > > ...{{dropped:25}}
> >
> > ______________________________________________
> > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> > https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guide
> > http://www.R-project.org/posting-guide.html
> > and provide commented, minimal, self-contained, reproducible code.
> Osobn? ?daje: Informace o zpracov?n? a ochran? osobn?ch ?daj?
> obchodn?ch partner? PRECHEZA a.s. jsou zve?ejn?ny na:
> https://www.precheza.cz/zasady- ochrany-osobnich-udaju/ | Information
> about processing and protection of business partner?s personal data are
available on website:
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> D?v?rnost: Tento e-mail a jak?koliv k n?mu p?ipojen? dokumenty jsou
> d?v?rn? a podl?haj? tomuto pr?vn? z?vazn?mu prohl??en? o vylou?en?
odpov?dnosti:
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> attached to it may be confidential and are subject to the legally
> binding
> disclaimer: https://www.precheza.cz/en/01-disclaimer/
>
>
>
> *******************************************************************
> *************************************************
>
> This message may contain confidential information. If you are not the
> intended recipient please inform the sender that you have received the
> message in error before deleting it.
> Please do not disclose, copy or distribute information in this e-mail
> or take any action in relation to its contents. To do so is strictly
> prohibited and may be unlawful. Thank you for your co-operation.
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> NHSmail is the secure email and directory service available for all
> NHS staff in England and Scotland. NHSmail is approved for exchanging
> patient data and other sensitive information with NHSmail and other
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>
> For more information and to find out how you can switch,
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Osobn? ?daje: Informace o zpracov?n? a ochran? osobn?ch ?daj? obchodn?ch
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https://www.precheza.cz/01-dovetek/ | This email and any documents attached to
it may be confidential and are subject to the legally binding disclaimer:
https://www.precheza.cz/en/01-disclaimer/



********************************************************************************************************************

This message may contain confidential information. If you are not the intended
recipient please inform the
sender that you have received the message in error before deleting it.
Please do not disclose, copy or distribute information in this e-mail or take
any action in relation to its contents. To do so is strictly prohibited and may
be unlawful. Thank you for your co-operation.

NHSmail is the secure email and directory service available for all NHS staff in
England and Scotland. NHSmail is approved for exchanging patient data and other
sensitive information with NHSmail and other accredited email services.

For more information and to find out how you can switch,
https://portal.nhs.net/help/joiningnhsmail

Jeff Newmiller

2019-Jan-17 15:06 UTC

head link

[R] I can't get seq to behave how I think it should

... then you still don't understand. Perhaps you might find [1] helpful.
Also, adding a floating point representation of 0.001 to 1.4 for 400 times does
not yield the same approximation of 1.8 that you get by directly converting the
string "1.8" that you typed into your R interpreter.

[1]
https://www.exploringbinary.com/why-0-point-1-does-not-exist-in-floating-point/

On January 17, 2019 6:56:48 AM PST, "POLWART, Calum (COUNTY DURHAM AND
DARLINGTON NHS FOUNDATION TRUST) via R-help" <r-help at
r-project.org> wrote:>Well I get the issue with finite precision. As in SQRT(2) * SQRT(2) is
>not 2.
>
>What surprised me was that seq(1.4, 2.1, by=0.001) starts at
>1.3999999999999999 and not 1.4!
>
>
>-----Original Message-----
>From: PIKAL Petr [mailto:petr.pikal at precheza.cz]
>Sent: 17 January 2019 14:30
>To: POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS FOUNDATION TRUST);
>Ben Tupper
>Cc: r-help at r-project.org
>Subject: RE: [R] I can't get seq to behave how I think it should
>
>Hi
>
>It is not seq problem, it is floating point numbers representation in
>finit precision problem. Ben pointed to it and you could learn about it
>from FAQ 7.31.
>
>Cheers
>Petr
>
>> -----Original Message-----
>> From: POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS FOUNDATION
>> TRUST) <calum.polwart at nhs.net>
>> Sent: Thursday, January 17, 2019 2:56 PM
>> To: PIKAL Petr <petr.pikal at precheza.cz>; Ben Tupper
>> <btupper at bigelow.org>
>> Cc: r-help at r-project.org
>> Subject: RE: [R] I can't get seq to behave how I think it should
>>
>> Thanks guys.
>>
>> I've used Petr's method and its working for me.
>>
>> If the data had been from a calculation I'd have rounded it... just
>> didn't expect seq to break it!
>>
>> C
>>
>> -----Original Message-----
>> From: PIKAL Petr [mailto:petr.pikal at precheza.cz]
>> Sent: 17 January 2019 13:53
>> To: Ben Tupper; POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS
>> FOUNDATION TRUST)
>> Cc: r-help at r-project.org
>> Subject: RE: [R] I can't get seq to behave how I think it should
>>
>> Hi
>>
>> Or you could use rounding.
>> which(round(lut, 3)==1.8)
>> [1] 401
>>
>> Cheers
>> Petr
>>
>> > -----Original Message-----
>> > From: R-help <r-help-bounces at r-project.org> On Behalf Of
Ben Tupper
>> > Sent: Thursday, January 17, 2019 2:43 PM
>> > To: POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS
>> FOUNDATION TRUST)
>> > <calum.polwart at nhs.net>
>> > Cc: r-help at r-project.org
>> > Subject: Re: [R] I can't get seq to behave how I think it
should
>> >
>> > Hi,
>> >
>> > This looks like a floating point reality bump - see
>> >
>> >
>https://cran.r-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-thin
>> > k- these-numbers-are-equal_003f
>> > <https://cran.r-project.org/doc/FAQ/R-
>> > FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f>
>> >
>> > You can use other methods to finding your row - I would opt for
>> > findInterval()
>> >
>> > > lut = seq(1.4, 2.1, by=0.001)
>> > > findInterval(1.8, lut)
>> > [1] 401
>> >
>> > findInterval() uses a rapid search to find the index in the look
up
>> > table (lut) that is just less than  or equal to the search value
>(in
>> > your example
>> 1.8).
>> >
>> > Cheers,
>> > Ben
>> >
>> > > On Jan 17, 2019, at 8:33 AM, POLWART, Calum (COUNTY DURHAM
AND
>> > DARLINGTON NHS FOUNDATION TRUST) via R-help <r-help at
r-project.org>
>> > wrote:
>> > >
>> > > I am using seq with the expression seq(1.4, 2.1, by=0.001) to
>> > > create a sequence of references from 1.4 to 2.1 in 0.001
>> > > increments.  They appear to be created correctly.  They have
a
>> > > related pair of data which for the purposes of this we will
call
>> > > val.  I'm interested in the content on the row with seq =
1.8.
>But
>> > > I can't seem to get it returned.  I can get other values
but not
>> > > 1.8!  yet looking at row
>> > > 401 there is nothing to indicate an issue
>> > >
>> > >> a = 1.4
>> > >> b = 2.1
>> > >> seq = seq(a, b, by=0.001)
>> > >> val = ceiling(seq * 50)
>> > >> s=data.frame(seq, val)
>> > >> s$val[seq==1.799]
>> > > [1] 90
>> > >> s$val[s$seq==1.8]
>> > > numeric(0)
>> > >> s$val[seq==1.8]
>> > > numeric(0)
>> > >> s$val[s$seq==1.800]
>> > > numeric(0)
>> > >> s$val[s$seq==1.801]
>> > > [1] 91
>> > >> head(s[s$seq>1.798,])
>> > >      seq val
>> > > 400 1.799  90
>> > > 401 1.800  90
>> > > 402 1.801  91
>> > > 403 1.802  91
>> > > 404 1.803  91
>> > > 405 1.804  91
>> > >
>> > >
>> > > Can anyone explain what's going on here and how I would
correctly
>> > > find the
>> > content of row 401 by using an expression to equal the seq column?
>> > >
>> > >
>> > >
>> > >
>> > >
>> > >
>> >
>> *******************************************************************
>> > ***
>> > > **********************************************
>> > >
>> > > This message may contain confidential information. If
>> > > ...{{dropped:25}}
>> >
>> > ______________________________________________
>> > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more,
see
>> > https://stat.ethz.ch/mailman/listinfo/r-help
>> > PLEASE do read the posting guide
>> > http://www.R-project.org/posting-guide.html
>> > and provide commented, minimal, self-contained, reproducible code.
>> Osobn? ?daje: Informace o zpracov?n? a ochran? osobn?ch ?daj?
>> obchodn?ch partner? PRECHEZA a.s. jsou zve?ejn?ny na:
>> https://www.precheza.cz/zasady- ochrany-osobnich-udaju/ | Information
>> about processing and protection of business partner?s personal data
>are available on website:
>> https://www.precheza.cz/en/personal-data-protection-principles/
>> D?v?rnost: Tento e-mail a jak?koliv k n?mu p?ipojen? dokumenty jsou
>> d?v?rn? a podl?haj? tomuto pr?vn? z?vazn?mu prohl??en? o vylou?en?
>odpov?dnosti:
>> https://www.precheza.cz/01-dovetek/ | This email and any documents
>> attached to it may be confidential and are subject to the legally
>> binding
>> disclaimer: https://www.precheza.cz/en/01-disclaimer/
>>
>>
>>
>> *******************************************************************
>> *************************************************
>>
>> This message may contain confidential information. If you are not the
>> intended recipient please inform the sender that you have received
>the
>> message in error before deleting it.
>> Please do not disclose, copy or distribute information in this e-mail
>> or take any action in relation to its contents. To do so is strictly
>> prohibited and may be unlawful. Thank you for your co-operation.
>>
>> NHSmail is the secure email and directory service available for all
>> NHS staff in England and Scotland. NHSmail is approved for exchanging
>> patient data and other sensitive information with NHSmail and other
>accredited email services.
>>
>> For more information and to find out how you can switch,
>> https://portal.nhs.net/help/joiningnhsmail
>
>Osobn? ?daje: Informace o zpracov?n? a ochran? osobn?ch ?daj?
>obchodn?ch partner? PRECHEZA a.s. jsou zve?ejn?ny na:
>https://www.precheza.cz/zasady-ochrany-osobnich-udaju/ | Information
>about processing and protection of business partner?s personal data are
>available on website:
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-- 
Sent from my phone. Please excuse my brevity.

peter dalgaard

2019-Jan-17 16:52 UTC

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[R] I can't get seq to behave how I think it should

> On 17 Jan 2019, at 15:56 , POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS
FOUNDATION TRUST) via R-help <r-help at r-project.org> wrote:
> 
> Well I get the issue with finite precision. As in SQRT(2) * SQRT(2) is not
2.
As Jeff indicates, you also need to get that just like 3rds and 7ths cannot be
represented exactly in base 10, 5ths and 10ths cannot be represented exactly in
base 2 (only powers of 1/2 and their multiples can).

Specifically, 1.4 decimal is 1.0110011001100.... binary

-pd
> 
> What surprised me was that seq(1.4, 2.1, by=0.001) starts at
1.3999999999999999 and not 1.4!
> 
> 
> -----Original Message-----
> From: PIKAL Petr [mailto:petr.pikal at precheza.cz]
> Sent: 17 January 2019 14:30
> To: POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS FOUNDATION TRUST); Ben
Tupper
> Cc: r-help at r-project.org
> Subject: RE: [R] I can't get seq to behave how I think it should
> 
> Hi
> 
> It is not seq problem, it is floating point numbers representation in finit
precision problem. Ben pointed to it and you could learn about it from FAQ 7.31.
> 
> Cheers
> Petr
> 
>> -----Original Message-----
>> From: POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS FOUNDATION
>> TRUST) <calum.polwart at nhs.net>
>> Sent: Thursday, January 17, 2019 2:56 PM
>> To: PIKAL Petr <petr.pikal at precheza.cz>; Ben Tupper
>> <btupper at bigelow.org>
>> Cc: r-help at r-project.org
>> Subject: RE: [R] I can't get seq to behave how I think it should
>> 
>> Thanks guys.
>> 
>> I've used Petr's method and its working for me.
>> 
>> If the data had been from a calculation I'd have rounded it... just
>> didn't expect seq to break it!
>> 
>> C
>> 
>> -----Original Message-----
>> From: PIKAL Petr [mailto:petr.pikal at precheza.cz]
>> Sent: 17 January 2019 13:53
>> To: Ben Tupper; POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS
>> FOUNDATION TRUST)
>> Cc: r-help at r-project.org
>> Subject: RE: [R] I can't get seq to behave how I think it should
>> 
>> Hi
>> 
>> Or you could use rounding.
>> which(round(lut, 3)==1.8)
>> [1] 401
>> 
>> Cheers
>> Petr
>> 
>>> -----Original Message-----
>>> From: R-help <r-help-bounces at r-project.org> On Behalf Of
Ben Tupper
>>> Sent: Thursday, January 17, 2019 2:43 PM
>>> To: POLWART, Calum (COUNTY DURHAM AND DARLINGTON NHS
>> FOUNDATION TRUST)
>>> <calum.polwart at nhs.net>
>>> Cc: r-help at r-project.org
>>> Subject: Re: [R] I can't get seq to behave how I think it
should
>>> 
>>> Hi,
>>> 
>>> This looks like a floating point reality bump - see
>>> 
>>>
https://cran.r-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-thin
>>> k- these-numbers-are-equal_003f
>>> <https://cran.r-project.org/doc/FAQ/R-
>>> FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f>
>>> 
>>> You can use other methods to finding your row - I would opt for
>>> findInterval()
>>> 
>>>> lut = seq(1.4, 2.1, by=0.001)
>>>> findInterval(1.8, lut)
>>> [1] 401
>>> 
>>> findInterval() uses a rapid search to find the index in the look up
>>> table (lut) that is just less than  or equal to the search value
(in
>>> your example
>> 1.8).
>>> 
>>> Cheers,
>>> Ben
>>> 
>>>> On Jan 17, 2019, at 8:33 AM, POLWART, Calum (COUNTY DURHAM AND
>>> DARLINGTON NHS FOUNDATION TRUST) via R-help <r-help at
r-project.org>
>>> wrote:
>>>> 
>>>> I am using seq with the expression seq(1.4, 2.1, by=0.001) to
>>>> create a sequence of references from 1.4 to 2.1 in 0.001
>>>> increments.  They appear to be created correctly.  They have a
>>>> related pair of data which for the purposes of this we will
call
>>>> val.  I'm interested in the content on the row with seq =
1.8. But
>>>> I can't seem to get it returned.  I can get other values
but not
>>>> 1.8!  yet looking at row
>>>> 401 there is nothing to indicate an issue
>>>> 
>>>>> a = 1.4
>>>>> b = 2.1
>>>>> seq = seq(a, b, by=0.001)
>>>>> val = ceiling(seq * 50)
>>>>> s=data.frame(seq, val)
>>>>> s$val[seq==1.799]
>>>> [1] 90
>>>>> s$val[s$seq==1.8]
>>>> numeric(0)
>>>>> s$val[seq==1.8]
>>>> numeric(0)
>>>>> s$val[s$seq==1.800]
>>>> numeric(0)
>>>>> s$val[s$seq==1.801]
>>>> [1] 91
>>>>> head(s[s$seq>1.798,])
>>>>     seq val
>>>> 400 1.799  90
>>>> 401 1.800  90
>>>> 402 1.801  91
>>>> 403 1.802  91
>>>> 404 1.803  91
>>>> 405 1.804  91
>>>> 
>>>> 
>>>> Can anyone explain what's going on here and how I would
correctly
>>>> find the
>>> content of row 401 by using an expression to equal the seq column?
>>>> 
>>>> 
>>>> 
>>>> 
>>>> 
>>>> 
>>> 
>> *******************************************************************
>>> ***
>>>> **********************************************
>>>> 
>>>> This message may contain confidential information. If
>>>> ...{{dropped:25}}
>>> 
>>> ______________________________________________
>>> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more,
see
>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>> PLEASE do read the posting guide
>>> http://www.R-project.org/posting-guide.html
>>> and provide commented, minimal, self-contained, reproducible code.
>> Osobn? ?daje: Informace o zpracov?n? a ochran? osobn?ch ?daj?
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>> about processing and protection of business partner?s personal data are
available on website:
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>> attached to it may be confidential and are subject to the legally
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>> disclaimer: https://www.precheza.cz/en/01-disclaimer/
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>> 
>> *******************************************************************
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>> 
>> This message may contain confidential information. If you are not the
>> intended recipient please inform the sender that you have received the
>> message in error before deleting it.
>> Please do not disclose, copy or distribute information in this e-mail
>> or take any action in relation to its contents. To do so is strictly
>> prohibited and may be unlawful. Thank you for your co-operation.
>> 
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>> NHS staff in England and Scotland. NHSmail is approved for exchanging
>> patient data and other sensitive information with NHSmail and other
accredited email services.
>> 
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> 
> Osobn? ?daje: Informace o zpracov?n? a ochran? osobn?ch ?daj? obchodn?ch
partner? PRECHEZA a.s. jsou zve?ejn?ny na:
https://www.precheza.cz/zasady-ochrany-osobnich-udaju/ | Information about
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website: https://www.precheza.cz/en/personal-data-protection-principles/
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a podl?haj? tomuto pr?vn? z?vazn?mu prohl??en? o vylou?en? odpov?dnosti:
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> 
> 
>
********************************************************************************************************************
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intended recipient please inform the
> sender that you have received the message in error before deleting it.
> Please do not disclose, copy or distribute information in this e-mail or
take any action in relation to its contents. To do so is strictly prohibited and
may be unlawful. Thank you for your co-operation.
> 
> NHSmail is the secure email and directory service available for all NHS
staff in England and Scotland. NHSmail is approved for exchanging patient data
and other sensitive information with NHSmail and other accredited email
services.
> 
> For more information and to find out how you can switch,
https://portal.nhs.net/help/joiningnhsmail
> 
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Office: A 4.23
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com

R help - Jan 2019 - I can't get seq to behave how I think it should

[R] I can't get seq to behave how I think it should

[R] I can't get seq to behave how I think it should

[R] I can't get seq to behave how I think it should

[R] I can't get seq to behave how I think it should