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Miluji Sb

2016-Nov-09 16:29 UTC

[R] Average every 4 columns

Dear all,

I have a dataset with hundreds of columns, I am only providing only 12
columns. Is it possible to take the mean of every four (or 12) columns
 (value601, value602, value603, value604 etc.in this case) and repeat for
the hundreds of columns? Thank you.

Sincerely,

Milu

structure(list(value601 = c(10.1738710403442, 3.54112911224365,
12.9192342758179, 3.17447590827942, 11.7332258224487, 7.68282270431519,
-7.11564493179321, 0.987620949745178, 13.0476207733154, 6.36939525604248
), value602 = c(13.0642414093018, 5.53129482269287, 16.0519638061523,
2.88946437835693, 14.9204912185669, 9.42428588867188, -6.80674123764038,
-0.614241063594818, 16.7947769165039, 7.9541072845459), value603
c(22.0399188995361,
14.398024559021, 24.9523792266846, 12.0878629684448, 23.6459674835205,
18.3277816772461, -2.54092741012573, 10.5550804138184, 25.1016540527344,
16.2166938781738), value604 = c(27.7165412902832, 20.3255825042725,
30.8430004119873, 16.6856250762939, 29.2485408782959, 24.3775005340576,
6.47758340835571, 15.5897912979126, 30.7387924194336, 22.3637084960938
), value605 = c(31.6644763946533, 23.4093952178955, 35.1488723754883,
19.7132263183594, 33.3924179077148, 29.5846366882324, 10.2083873748779,
19.3551616668701, 35.3076629638672, 27.4299201965332), value606
c(33.9698333740234,
26.8574161529541, 36.8900833129883, 22.8604583740234, 34.8642921447754,
33.8158760070801, 14.7055835723877, 22.1144580841064, 37.0545425415039,
32.1087913513184), value607 = c(36.0279846191406, 26.9297180175781,
38.2701225280762, 23.2643146514893, 36.7398796081543, 34.1216125488281,
17.1387901306152, 24.0419750213623, 37.8542327880859, 32.7677421569824
), value608 = c(34.0242347717285, 25.7720966339111, 36.4897193908691,
22.0332260131836, 34.8011703491211, 32.6856842041016, 16.6232261657715,
21.5571365356445, 36.1491546630859, 31.1716938018799), value609
c(27.5402088165283,
21.7590408325195, 30.5214176177979, 18.4252090454102, 29.1156253814697,
26.9878330230713, 12.4962501525879, 17.7259578704834, 30.9099159240723,
25.4832077026367), value610 = c(23.4706859588623, 17.0126209259033,
26.8166942596436, 15.297459602356, 25.1733055114746, 23.5616931915283,
8.86995983123779, 13.5793552398682, 27.5732250213623, 22.1691932678223
), value611 = c(14.5820417404175, 9.08279132843018, 17.8419170379639,
8.36016654968262, 16.5633754730225, 14.8123331069946, 1.32095837593079,
5.73408317565918, 18.9752082824707, 13.5729999542236), value612
c(9.12979793548584,
2.79943537712097, 11.6504030227661, 2.21584677696228, 10.5404834747314,
7.55471754074097, -5.58141136169434, -0.566209673881531, 12.3264112472534,
6.65576601028442)), .Names = c("value601", "value602",
"value603",
"value604", "value605", "value606",
"value607", "value608", "value609",
"value610", "value611", "value612"), row.names =
c("1", "2",
"3", "4", "5", "6", "7",
"8", "9", "10"), class = "data.frame")

	[[alternative HTML version deleted]]

Dalthorp, Daniel

2016-Nov-09 16:45 UTC

head link

[R] Average every 4 columns

Hi Milu,
The following should work for an array x (provided dim(x)[2] is divisible
by 4):

colMeans(x[,0:(dim(x)[2]/4-1)*4+1])

-Dan

On Wed, Nov 9, 2016 at 8:29 AM, Miluji Sb <milujisb at gmail.com> wrote:
> Dear all,
>
> I have a dataset with hundreds of columns, I am only providing only 12
> columns. Is it possible to take the mean of every four (or 12) columns
>  (value601, value602, value603, value604 etc.in this case) and repeat for
> the hundreds of columns? Thank you.
>
> Sincerely,
>
> Milu
>
> structure(list(value601 = c(10.1738710403442, 3.54112911224365,
> 12.9192342758179, 3.17447590827942, 11.7332258224487, 7.68282270431519,
> -7.11564493179321, 0.987620949745178, 13.0476207733154, 6.36939525604248
> ), value602 = c(13.0642414093018, 5.53129482269287, 16.0519638061523,
> 2.88946437835693, 14.9204912185669, 9.42428588867188, -6.80674123764038,
> -0.614241063594818, 16.7947769165039, 7.9541072845459), value603 >
c(22.0399188995361,
> 14.398024559021, 24.9523792266846, 12.0878629684448, 23.6459674835205,
> 18.3277816772461, -2.54092741012573, 10.5550804138184, 25.1016540527344,
> 16.2166938781738), value604 = c(27.7165412902832, 20.3255825042725,
> 30.8430004119873, 16.6856250762939, 29.2485408782959, 24.3775005340576,
> 6.47758340835571, 15.5897912979126, 30.7387924194336, 22.3637084960938
> ), value605 = c(31.6644763946533, 23.4093952178955, 35.1488723754883,
> 19.7132263183594, 33.3924179077148, 29.5846366882324, 10.2083873748779,
> 19.3551616668701, 35.3076629638672, 27.4299201965332), value606 >
c(33.9698333740234,
> 26.8574161529541, 36.8900833129883, 22.8604583740234, 34.8642921447754,
> 33.8158760070801, 14.7055835723877, 22.1144580841064, 37.0545425415039,
> 32.1087913513184), value607 = c(36.0279846191406, 26.9297180175781,
> 38.2701225280762, 23.2643146514893, 36.7398796081543, 34.1216125488281,
> 17.1387901306152, 24.0419750213623, 37.8542327880859, 32.7677421569824
> ), value608 = c(34.0242347717285, 25.7720966339111, 36.4897193908691,
> 22.0332260131836, 34.8011703491211, 32.6856842041016, 16.6232261657715,
> 21.5571365356445, 36.1491546630859, 31.1716938018799), value609 >
c(27.5402088165283,
> 21.7590408325195, 30.5214176177979, 18.4252090454102, 29.1156253814697,
> 26.9878330230713, 12.4962501525879, 17.7259578704834, 30.9099159240723,
> 25.4832077026367), value610 = c(23.4706859588623, 17.0126209259033,
> 26.8166942596436, 15.297459602356, 25.1733055114746, 23.5616931915283,
> 8.86995983123779, 13.5793552398682, 27.5732250213623, 22.1691932678223
> ), value611 = c(14.5820417404175, 9.08279132843018, 17.8419170379639,
> 8.36016654968262, 16.5633754730225, 14.8123331069946, 1.32095837593079,
> 5.73408317565918, 18.9752082824707, 13.5729999542236), value612 >
c(9.12979793548584,
> 2.79943537712097, 11.6504030227661, 2.21584677696228, 10.5404834747314,
> 7.55471754074097, -5.58141136169434, -0.566209673881531, 12.3264112472534,
> 6.65576601028442)), .Names = c("value601", "value602",
"value603",
> "value604", "value605", "value606",
"value607", "value608", "value609",
> "value610", "value611", "value612"),
row.names = c("1", "2",
> "3", "4", "5", "6", "7",
"8", "9", "10"), class = "data.frame")
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> 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.
>
>

-- 
Dan Dalthorp, PhD
USGS Forest and Rangeland Ecosystem Science Center
Forest Sciences Lab, Rm 189
3200 SW Jefferson Way
Corvallis, OR 97331
ph: 541-750-0953
ddalthorp at usgs.gov

	[[alternative HTML version deleted]]

Miluji Sb

2016-Nov-09 17:00 UTC

head link

[R] Average every 4 columns

Thanks a lot for your quick reply. I made a mistake in the question, I
meant to ask every 4 (or 12) rows not columns. Apologies. Thanks again!

Sincerely,

Milu

On Wed, Nov 9, 2016 at 5:45 PM, Dalthorp, Daniel <ddalthorp at usgs.gov>
wrote:
> Hi Milu,
> The following should work for an array x (provided dim(x)[2] is divisible
> by 4):
>
> colMeans(x[,0:(dim(x)[2]/4-1)*4+1])
>
> -Dan
>
> On Wed, Nov 9, 2016 at 8:29 AM, Miluji Sb <milujisb at gmail.com>
wrote:
>
>> Dear all,
>>
>> I have a dataset with hundreds of columns, I am only providing only 12
>> columns. Is it possible to take the mean of every four (or 12) columns
>>  (value601, value602, value603, value604 etc.in this case) and repeat
for
>> the hundreds of columns? Thank you.
>>
>> Sincerely,
>>
>> Milu
>>
>> structure(list(value601 = c(10.1738710403442, 3.54112911224365,
>> 12.9192342758179, 3.17447590827942, 11.7332258224487, 7.68282270431519,
>> -7.11564493179321, 0.987620949745178, 13.0476207733154,
6.36939525604248
>> ), value602 = c(13.0642414093018, 5.53129482269287, 16.0519638061523,
>> 2.88946437835693, 14.9204912185669, 9.42428588867188,
-6.80674123764038,
>> -0.614241063594818, 16.7947769165039, 7.9541072845459), value603
>> c(22.0399188995361,
>> 14.398024559021, 24.9523792266846, 12.0878629684448, 23.6459674835205,
>> 18.3277816772461, -2.54092741012573, 10.5550804138184,
25.1016540527344,
>> 16.2166938781738), value604 = c(27.7165412902832, 20.3255825042725,
>> 30.8430004119873, 16.6856250762939, 29.2485408782959, 24.3775005340576,
>> 6.47758340835571, 15.5897912979126, 30.7387924194336, 22.3637084960938
>> ), value605 = c(31.6644763946533, 23.4093952178955, 35.1488723754883,
>> 19.7132263183594, 33.3924179077148, 29.5846366882324, 10.2083873748779,
>> 19.3551616668701, 35.3076629638672, 27.4299201965332), value606
>> c(33.9698333740234,
>> 26.8574161529541, 36.8900833129883, 22.8604583740234, 34.8642921447754,
>> 33.8158760070801, 14.7055835723877, 22.1144580841064, 37.0545425415039,
>> 32.1087913513184), value607 = c(36.0279846191406, 26.9297180175781,
>> 38.2701225280762, 23.2643146514893, 36.7398796081543, 34.1216125488281,
>> 17.1387901306152, 24.0419750213623, 37.8542327880859, 32.7677421569824
>> ), value608 = c(34.0242347717285, 25.7720966339111, 36.4897193908691,
>> 22.0332260131836, 34.8011703491211, 32.6856842041016, 16.6232261657715,
>> 21.5571365356445, 36.1491546630859, 31.1716938018799), value609
>> c(27.5402088165283,
>> 21.7590408325195, 30.5214176177979, 18.4252090454102, 29.1156253814697,
>> 26.9878330230713, 12.4962501525879, 17.7259578704834, 30.9099159240723,
>> 25.4832077026367), value610 = c(23.4706859588623, 17.0126209259033,
>> 26.8166942596436, 15.297459602356, 25.1733055114746, 23.5616931915283,
>> 8.86995983123779, 13.5793552398682, 27.5732250213623, 22.1691932678223
>> ), value611 = c(14.5820417404175, 9.08279132843018, 17.8419170379639,
>> 8.36016654968262, 16.5633754730225, 14.8123331069946, 1.32095837593079,
>> 5.73408317565918, 18.9752082824707, 13.5729999542236), value612
>> c(9.12979793548584,
>> 2.79943537712097, 11.6504030227661, 2.21584677696228, 10.5404834747314,
>> 7.55471754074097, -5.58141136169434, -0.566209673881531,
12.3264112472534,
>> 6.65576601028442)), .Names = c("value601",
"value602", "value603",
>> "value604", "value605", "value606",
"value607", "value608", "value609",
>> "value610", "value611", "value612"),
row.names = c("1", "2",
>> "3", "4", "5", "6",
"7", "8", "9", "10"), class =
"data.frame")
>>
>>         [[alternative HTML version deleted]]
>>
>> ______________________________________________
>> 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/posti
>> ng-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
>>
>
>
> --
> Dan Dalthorp, PhD
> USGS Forest and Rangeland Ecosystem Science Center
> Forest Sciences Lab, Rm 189
> 3200 SW Jefferson Way
> Corvallis, OR 97331
> ph: 541-750-0953
> ddalthorp at usgs.gov
>
>
	[[alternative HTML version deleted]]

Jim Lemon

2016-Nov-12 22:12 UTC

head link

[R] Average every 4 columns

Hi Miluj,
Perhaps you didn't get my previous email. Let your data frame be named
"msdf":

block_col_summ<-function(x,step,block_size,FUN="mean") {
 dimx<-dim(x)
 return_value<-NA
 start<-1
 end<-start+block_size-1
 block_count<-1
 while(end <= dimx[2]) {
  return_value[block_count]<-
   do.call(FUN,list(as.matrix(x[,start:end]),na.rm=TRUE))
  block_count<-block_count+1
  start<-start+step
  end<-start+block_size-1
 }
 return(return_value)
}
# use the step and block size that you want
block_col_summ(msdf,4,4)

Jim


On Thu, Nov 10, 2016 at 3:29 AM, Miluji Sb <milujisb at gmail.com>
wrote:> Dear all,
>
> I have a dataset with hundreds of columns, I am only providing only 12
> columns. Is it possible to take the mean of every four (or 12) columns
>  (value601, value602, value603, value604 etc.in this case) and repeat for
> the hundreds of columns? Thank you.
>
> Sincerely,
>
> Milu
>
> structure(list(value601 = c(10.1738710403442, 3.54112911224365,
> 12.9192342758179, 3.17447590827942, 11.7332258224487, 7.68282270431519,
> -7.11564493179321, 0.987620949745178, 13.0476207733154, 6.36939525604248
> ), value602 = c(13.0642414093018, 5.53129482269287, 16.0519638061523,
> 2.88946437835693, 14.9204912185669, 9.42428588867188, -6.80674123764038,
> -0.614241063594818, 16.7947769165039, 7.9541072845459), value603 >
c(22.0399188995361,
> 14.398024559021, 24.9523792266846, 12.0878629684448, 23.6459674835205,
> 18.3277816772461, -2.54092741012573, 10.5550804138184, 25.1016540527344,
> 16.2166938781738), value604 = c(27.7165412902832, 20.3255825042725,
> 30.8430004119873, 16.6856250762939, 29.2485408782959, 24.3775005340576,
> 6.47758340835571, 15.5897912979126, 30.7387924194336, 22.3637084960938
> ), value605 = c(31.6644763946533, 23.4093952178955, 35.1488723754883,
> 19.7132263183594, 33.3924179077148, 29.5846366882324, 10.2083873748779,
> 19.3551616668701, 35.3076629638672, 27.4299201965332), value606 >
c(33.9698333740234,
> 26.8574161529541, 36.8900833129883, 22.8604583740234, 34.8642921447754,
> 33.8158760070801, 14.7055835723877, 22.1144580841064, 37.0545425415039,
> 32.1087913513184), value607 = c(36.0279846191406, 26.9297180175781,
> 38.2701225280762, 23.2643146514893, 36.7398796081543, 34.1216125488281,
> 17.1387901306152, 24.0419750213623, 37.8542327880859, 32.7677421569824
> ), value608 = c(34.0242347717285, 25.7720966339111, 36.4897193908691,
> 22.0332260131836, 34.8011703491211, 32.6856842041016, 16.6232261657715,
> 21.5571365356445, 36.1491546630859, 31.1716938018799), value609 >
c(27.5402088165283,
> 21.7590408325195, 30.5214176177979, 18.4252090454102, 29.1156253814697,
> 26.9878330230713, 12.4962501525879, 17.7259578704834, 30.9099159240723,
> 25.4832077026367), value610 = c(23.4706859588623, 17.0126209259033,
> 26.8166942596436, 15.297459602356, 25.1733055114746, 23.5616931915283,
> 8.86995983123779, 13.5793552398682, 27.5732250213623, 22.1691932678223
> ), value611 = c(14.5820417404175, 9.08279132843018, 17.8419170379639,
> 8.36016654968262, 16.5633754730225, 14.8123331069946, 1.32095837593079,
> 5.73408317565918, 18.9752082824707, 13.5729999542236), value612 >
c(9.12979793548584,
> 2.79943537712097, 11.6504030227661, 2.21584677696228, 10.5404834747314,
> 7.55471754074097, -5.58141136169434, -0.566209673881531, 12.3264112472534,
> 6.65576601028442)), .Names = c("value601", "value602",
"value603",
> "value604", "value605", "value606",
"value607", "value608", "value609",
> "value610", "value611", "value612"),
row.names = c("1", "2",
> "3", "4", "5", "6", "7",
"8", "9", "10"), class = "data.frame")
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> 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.

R help - Nov 2016 - Average every 4 columns

[R] Average every 4 columns

[R] Average every 4 columns

[R] Average every 4 columns

[R] Average every 4 columns