From luke-tierney at uiowa.edu  Wed Feb 18 15:04:42 2015
From: luke-tierney at uiowa.edu (luke-tierney at uiowa.edu)
Date: Wed, 18 Feb 2015 08:04:42 -0600
Subject: [Rd] Different serialization of functions in interactive vs.
 batch	mode
In-Reply-To: <CAFDswJvq5T2sZNQyE1pDP_F9CGBFQfxrXHbzfKhB4CZPgXNO8g@mail.gmail.com>
References: <CAFDswJvq5T2sZNQyE1pDP_F9CGBFQfxrXHbzfKhB4CZPgXNO8g@mail.gmail.com>
Message-ID: <alpine.DEB.2.02.1502180804090.2336@luke-Latitude>

Add

attributes(testfun)

and you will see where the two functions differ.

luke

On Wed, 18 Feb 2015, Holger Hoefling wrote:

> Hi,
>
> I posted this question to the regular help list, but it seems to be
> this is probably a question that is better addressed on r-devel. Sorry
> for the double posting.
>
> I am using hash-values to cache certain results in R. This caching
> also depends on the hash-value of the function that is being cached
> (calculated using the digest package). I noticed that computations
> that should already be cached are recomputed when switching from an
> interactive session to a BATCH session. Therefore, I wrote a test
> script
>
> library(digest)
> testfun <- function() {
>    return(NULL)
> }
> testval <- "testval"
> print(digest(testfun))
> print(serialize(testfun, connection = NULL))
>
> and executed it once using input-redirection from a file (testFile.R)
> and once copying the code into an interactive R session. The
> hash-values of the functions differ. As digest internally relies on
> serialize, I also checked there and found that digest is not the
> reason for the discrepancy. Instead, the serialized value of the
> function already differs between the BATCH and inteactive sessions.
>
> I was wondering if someone knows if
> 1. Is this a feature or a bug? It feels like a bug to me as all the
> inputs are identical, I would expect that the output is identical as
> well. Is there something I am overlooking?
> 2. Is there a way to get consistent hash-values for functions between
> BATCH and interactive sessions.
>
> The output from the BATCH and interactive runs are below (as well as
> sessionInfo)
>
> Thank you very much for your help!
>
> Holger Hoefling
>
> ---------------------------------
> BATCH run (via input redirection):
>
> $ R --vanilla < testFile.R
>
> R version 3.1.0 (2014-04-10) -- "Spring Dance"
> Copyright (C) 2014 The R Foundation for Statistical Computing
> Platform: x86_64-unknown-linux-gnu (64-bit)
>
> R is free software and comes with ABSOLUTELY NO WARRANTY.
> You are welcome to redistribute it under certain conditions.
> Type 'license()' or 'licence()' for distribution details.
>
> R is a collaborative project with many contributors.
> Type 'contributors()' for more information and
> 'citation()' on how to cite R or R packages in publications.
>
> Type 'demo()' for some demos, 'help()' for on-line help, or
> 'help.start()' for an HTML browser interface to help.
> Type 'q()' to quit R.
>
>> library(digest)
>> testfun <- function() {
> +     return(NULL)
> + }
>> print(digest(testfun))
> [1] "b03160b9250f0d5b5bcce42bd86d8e56"
>> print(serialize(testfun, connection = NULL))
> [1] 58 0a 00 00 00 02 00 03 01 00 00 02 03 00 00 00 04 03 00 00 00 fd 00 00 00
> [26] fe 00 00 00 06 00 00 00 01 00 04 00 09 00 00 00 01 7b 00 00 00 02 00 00 00
> [51] 06 00 00 00 01 00 04 00 09 00 00 00 06 72 65 74 75 72 6e 00 00 00 02 00 00
> [76] 00 fe 00 00 00 fe 00 00 00 fe
>> sessionInfo()
> R version 3.1.0 (2014-04-10)
> Platform: x86_64-unknown-linux-gnu (64-bit)
>
> locale:
> [1] C
>
> attached base packages:
> [1] stats     graphics  grDevices utils     datasets  methods   base
>
> other attached packages:
> [1] digest_0.6.4
>>
>
> ----------------------------------------------
> Interactive run:
>
> $ R --vanilla
>
> R version 3.1.0 (2014-04-10) -- "Spring Dance"
> Copyright (C) 2014 The R Foundation for Statistical Computing
> Platform: x86_64-unknown-linux-gnu (64-bit)
>
> R is free software and comes with ABSOLUTELY NO WARRANTY.
> You are welcome to redistribute it under certain conditions.
> Type 'license()' or 'licence()' for distribution details.
>
> R is a collaborative project with many contributors.
> Type 'contributors()' for more information and
> 'citation()' on how to cite R or R packages in publications.
>
> Type 'demo()' for some demos, 'help()' for on-line help, or
> 'help.start()' for an HTML browser interface to help.
> Type 'q()' to quit R.
>
>> library(digest)
>> testfun <- function() {
> +     return(NULL)
> + }
>> print(digest(testfun))
> [1] "fada482d2894088b079a8e56b7044862"
>> print(serialize(testfun, connection = NULL))
>  [1] 58 0a 00 00 00 02 00 03 01 00 00 02 03 00 00 00 06 03 00 00 04 02 00 00 00
> [26] 01 00 04 00 09 00 00 00 06 73 72 63 72 65 66 00 00 03 0d 00 00 00 08 00 00
> [51] 00 01 00 00 00 0c 00 00 00 03 00 00 00 01 00 00 00 0c 00 00 00 01 00 00 00
> [76] 01 00 00 00 03 00 00 04 02 00 00 00 01 00 04 00 09 00 00 00 07 73 72 63 66
> [101] 69 6c 65 00 00 00 04 00 00 00 00 00 00 00 f2 00 00 04 02 00 00 00 01 00 04
> [126] 00 09 00 00 00 05 6c 69 6e 65 73 00 00 00 10 00 00 00 01 00 04 00 09 00 00
> [151] 00 2b 74 65 73 74 66 75 6e 20 3c 2d 20 66 75 6e 63 74 69 6f 6e 28 29 20 7b
> [176] 0a 20 20 20 20 72 65 74 75 72 6e 28 4e 55 4c 4c 29 0a 7d 0a 00 00 04 02 00
> [201] 00 00 01 00 04 00 09 00 00 00 08 66 69 6c 65 6e 61 6d 65 00 00 00 10 00 00
> [226] 00 01 00 04 00 09 00 00 00 00 00 00 00 fe 00 00 00 fe 00 00 04 02 00 00 00
> [251] 01 00 04 00 09 00 00 00 05 63 6c 61 73 73 00 00 00 10 00 00 00 02 00 04 00
> [276] 09 00 00 00 0b 73 72 63 66 69 6c 65 63 6f 70 79 00 04 00 09 00 00 00 07 73
> [301] 72 63 66 69 6c 65 00 00 00 fe 00 00 04 02 00 00 06 ff 00 00 00 10 00 00 00
> [326] 01 00 04 00 09 00 00 00 06 73 72 63 72 65 66 00 00 00 fe 00 00 00 fe 00 00
> [351] 00 fd 00 00 00 fe 00 00 02 06 00 00 04 02 00 00 01 ff 00 00 00 13 00 00 00
> [376] 02 00 00 03 0d 00 00 00 08 00 00 00 01 00 00 00 17 00 00 00 01 00 00 00 17
> [401] 00 00 00 17 00 00 00 17 00 00 00 01 00 00 00 01 00 00 04 02 00 00 02 ff 00
> [426] 00 03 ff 00 00 04 02 00 00 06 ff 00 00 00 10 00 00 00 01 00 04 00 09 00 00
> [451] 00 06 73 72 63 72 65 66 00 00 00 fe 00 00 03 0d 00 00 00 08 00 00 00 02 00
> [476] 00 00 05 00 00 00 02 00 00 00 10 00 00 00 05 00 00 00 10 00 00 00 02 00 00
> [501] 00 02 00 00 04 02 00 00 02 ff 00 00 03 ff 00 00 04 02 00 00 06 ff 00 00 00
> [526] 10 00 00 00 01 00 04 00 09 00 00 00 06 73 72 63 72 65 66 00 00 00 fe 00 00
> [551] 04 02 00 00 02 ff 00 00 03 ff 00 00 04 02 00 00 00 01 00 04 00 09 00 00 00
> [576] 0b 77 68 6f 6c 65 53 72 63 72 65 66 00 00 03 0d 00 00 00 08 00 00 00 01 00
> [601] 00 00 00 00 00 00 03 00 00 00 01 00 00 00 00 00 00 00 01 00 00 00 01 00 00
> [626] 00 03 00 00 04 02 00 00 02 ff 00 00 03 ff 00 00 04 02 00 00 06 ff 00 00 00
> [651] 10 00 00 00 01 00 04 00 09 00 00 00 06 73 72 63 72 65 66 00 00 00 fe 00 00
> [676] 00 fe 00 00 00 01 00 04 00 09 00 00 00 01 7b 00 00 00 02 00 00 00 06 00 00
> [701] 00 01 00 04 00 09 00 00 00 06 72 65 74 75 72 6e 00 00 00 02 00 00 00 fe 00
> [726] 00 00 fe 00 00 00 fe
>> sessionInfo()
> R version 3.1.0 (2014-04-10)
> Platform: x86_64-unknown-linux-gnu (64-bit)
>
> locale:
> [1] C
>
> attached base packages:
> [1] stats     graphics  grDevices utils     datasets  methods   base
>
> other attached packages:
> [1] digest_0.6.4
>>
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>

-- 
Luke Tierney
Ralph E. Wareham Professor of Mathematical Sciences
University of Iowa                  Phone:             319-335-3386
Department of Statistics and        Fax:               319-335-3017
    Actuarial Science
241 Schaeffer Hall                  email:   luke-tierney at uiowa.edu
Iowa City, IA 52242                 WWW:  http://www.stat.uiowa.edu



[Rd] Different serialization of functions in interactive vs. batch mode
luke-tierney at uiowa.edu