Aggregating daily rainfall raster data to bimontly data

-----Original Message-----
From: johnwasige at gmail.com
Sent: Sun, 5 Apr 2015 11:34:30 +0200
To: r-help at r-project.org
Subject: [R] Aggregating daily rainfall raster data to bimontly data

Dear community,

I have daily rainfall raster data for 30 years (1982_2011). I would like
to
aggregate daily to bimonthly raster data. Could somebody kindly help on
how
to go about it!

Thanks for your help

--
John

	[[alternative HTML version deleted]]

Someone might if they had any idea of what the data actually looked like and what you are trying to do. The 'bimonthly' for example, is ambiguous in English; do you mean every two months or twice a month?

Have a look at https://github.com/hadley/devtools/wiki/Reproducibility and   http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example with special attention to dput() as a method of supplying sample data to the help list.

John Kane
Kingston ON Canada

-----Original Message-----
From: johnwasige at gmail.com
Sent: Sun, 5 Apr 2015 11:34:30 +0200
To: r-help at r-project.org
Subject: [R] Aggregating daily rainfall raster data to bimontly data

Dear community,

I have daily rainfall raster data for 30 years (1982_2011). I would like
to
aggregate daily to bimonthly raster data. Could somebody kindly help on
how
to go about it!

Thanks for your help

--
John

      [[alternative HTML version deleted]]

See ?tapply

However, as John said, without knowing the structure of your data, it
is impossible to provide a guaranteed recipe. For example, does the
data structure contain date information? -- it would be difficult (but
not impossible depending on data structure) to aggregate by calendar
(bi-monthly, depending on your meaning of "bi") without knowing the
months. Aggregating by every n days would be easy, but that's probably
not what you want.

Cheers,
Bert

Bert Gunter
Genentech Nonclinical Biostatistics
(650) 467-7374

"Data is not information. Information is not knowledge. And knowledge
is certainly not wisdom."
Clifford Stoll




On Sun, Apr 5, 2015 at 9:13 AM, John Kane <jrkrideau at inbox.com> wrote:

Someone might if they had any idea of what the data actually looked like

and what you are trying to do. The 'bimonthly' for example, is ambiguous in
English; do you mean every two months or twice a month?

Have a look at https://github.com/hadley/devtools/wiki/Reproducibility

and
http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example
with special attention to dput() as a method of supplying sample data to
the help list.

John Kane
Kingston ON Canada

-----Original Message-----
From: johnwasige at gmail.com
Sent: Sun, 5 Apr 2015 11:34:30 +0200
To: r-help at r-project.org
Subject: [R] Aggregating daily rainfall raster data to bimontly data

Dear community,

I have daily rainfall raster data for 30 years (1982_2011). I would like
to
aggregate daily to bimonthly raster data. Could somebody kindly help on
how
to go about it!

Thanks for your help

--
John

      [[alternative HTML version deleted]]

and family!

Visit http://www.inbox.com/photosharing to find out more!

Thanks Bert,

The structure of the data is a raster stack with nraw=867, Ncol=995

Rgds John


On Sun, Apr 5, 2015 at 6:39 PM, Bert Gunter <gunter.berton at gene.com>
wrote:

See ?tapply

However, as John said, without knowing the structure of your data, it
is impossible to provide a guaranteed recipe. For example, does the
data structure contain date information? -- it would be difficult

(but

not impossible depending on data structure) to aggregate by calendar
(bi-monthly, depending on your meaning of "bi") without knowing the
months. Aggregating by every n days would be easy, but that's

probably

not what you want.

Cheers,
Bert

Bert Gunter
Genentech Nonclinical Biostatistics
(650) 467-7374

"Data is not information. Information is not knowledge. And knowledge
is certainly not wisdom."
Clifford Stoll




On Sun, Apr 5, 2015 at 9:13 AM, John Kane <jrkrideau at inbox.com>

wrote:

Someone might if they had any idea of what the data actually looked

like

and what you are trying to do. The 'bimonthly' for example, is

ambiguous in

English; do you mean every two months or twice a month?

Have a look at

https://github.com/hadley/devtools/wiki/Reproducibility

and

http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example

with special attention to dput() as a method of supplying sample data

to

the help list.

John Kane
Kingston ON Canada

-----Original Message-----
From: johnwasige at gmail.com
Sent: Sun, 5 Apr 2015 11:34:30 +0200
To: r-help at r-project.org
Subject: [R] Aggregating daily rainfall raster data to bimontly

data

Dear community,

I have daily rainfall raster data for 30 years (1982_2011). I

would like

to
aggregate daily to bimonthly raster data. Could somebody kindly

help on

how
to go about it!

Thanks for your help

--
John

      [[alternative HTML version deleted]]

friends

and family!

Visit http://www.inbox.com/photosharing to find out more!

[[alternative HTML version deleted]]

Please stop posting using HTML (as the Posting Guide warns you), and
follow John Kane's advice. Your reply below is not helping us understand as
well as you seem to think it should.
---------------------------------------------------------------------------
Jeff Newmiller                        The     .....       .....  Go Live...
DCN:<jdnewmil at dcn.davis.ca.us>        Basics: ##.#.       ##.#.  Live
Go...
                                      Live:   OO#.. Dead: OO#..  Playing
Research Engineer (Solar/Batteries            O.O#.       #.O#.  with
/Software/Embedded Controllers)               .OO#.       .OO#.  rocks...1k
---------------------------------------------------------------------------
Sent from my phone. Please excuse my brevity.

On April 5, 2015 9:52:18 AM PDT, John Wasige <johnwasige at gmail.com> wrote:

Thanks Bert,

The structure of the data is a raster stack with nraw=867, Ncol=995

Rgds John


On Sun, Apr 5, 2015 at 6:39 PM, Bert Gunter <gunter.berton at gene.com>
wrote:

See ?tapply

However, as John said, without knowing the structure of your data, it
is impossible to provide a guaranteed recipe. For example, does the
data structure contain date information? -- it would be difficult

(but

not impossible depending on data structure) to aggregate by calendar
(bi-monthly, depending on your meaning of "bi") without knowing the
months. Aggregating by every n days would be easy, but that's

probably

not what you want.

Cheers,
Bert

Bert Gunter
Genentech Nonclinical Biostatistics
(650) 467-7374

"Data is not information. Information is not knowledge. And knowledge
is certainly not wisdom."
Clifford Stoll




On Sun, Apr 5, 2015 at 9:13 AM, John Kane <jrkrideau at inbox.com>

wrote:

Someone might if they had any idea of what the data actually looked

like

and what you are trying to do. The 'bimonthly' for example, is

ambiguous in

English; do you mean every two months or twice a month?

Have a look at

https://github.com/hadley/devtools/wiki/Reproducibility

and

http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example

with special attention to dput() as a method of supplying sample data

to

the help list.

John Kane
Kingston ON Canada

-----Original Message-----
From: johnwasige at gmail.com
Sent: Sun, 5 Apr 2015 11:34:30 +0200
To: r-help at r-project.org
Subject: [R] Aggregating daily rainfall raster data to bimontly

data

Dear community,

I have daily rainfall raster data for 30 years (1982_2011). I

would like

to
aggregate daily to bimonthly raster data. Could somebody kindly

help on

how
to go about it!

Thanks for your help

--
John

      [[alternative HTML version deleted]]

friends

and family!

Visit http://www.inbox.com/photosharing to find out more!

      [[alternative HTML version deleted]]

Hi John,
One way is to create an index variable that will divide your data into the
appropriate intervals. There are a number of ways to do this. Say you want
the "two month" version of bimonthly and you have a date variable
("raindate") for each observation like "1982-01-01".

date_order<-paste(rep(month.abb,30),rep(1982:2011,each=12),sep="")

month_index<-factor(format(as.Date(raindate,"%Y-%m-%d"),"%b%Y"),levels=date_order)

You can then subset the raster matrices by "month_index" and average them
for each group

Jim

On Mon, Apr 6, 2015 at 3:08 AM, Jeff Newmiller <jdnewmil at dcn.davis.ca.us>
wrote:

Please stop posting using HTML (as the Posting Guide warns you), and
follow John Kane's advice. Your reply below is not helping us understand as
well as you seem to think it should.

---------------------------------------------------------------------------
Jeff Newmiller                        The     .....       .....  Go
Live...
DCN:<jdnewmil at dcn.davis.ca.us>        Basics: ##.#.       ##.#.  Live
Go...
                                      Live:   OO#.. Dead: OO#..  Playing
Research Engineer (Solar/Batteries            O.O#.       #.O#.  with
/Software/Embedded Controllers)               .OO#.       .OO#.
rocks...1k

---------------------------------------------------------------------------
Sent from my phone. Please excuse my brevity.

On April 5, 2015 9:52:18 AM PDT, John Wasige <johnwasige at gmail.com>
wrote:

Thanks Bert,

The structure of the data is a raster stack with nraw=867, Ncol=995

Rgds John


On Sun, Apr 5, 2015 at 6:39 PM, Bert Gunter <gunter.berton at gene.com>
wrote:

See ?tapply

However, as John said, without knowing the structure of your data, it
is impossible to provide a guaranteed recipe. For example, does the
data structure contain date information? -- it would be difficult

(but

not impossible depending on data structure) to aggregate by calendar
(bi-monthly, depending on your meaning of "bi") without knowing the
months. Aggregating by every n days would be easy, but that's

probably

not what you want.

Cheers,
Bert

Bert Gunter
Genentech Nonclinical Biostatistics
(650) 467-7374

"Data is not information. Information is not knowledge. And knowledge
is certainly not wisdom."
Clifford Stoll




On Sun, Apr 5, 2015 at 9:13 AM, John Kane <jrkrideau at inbox.com>

wrote:

Someone might if they had any idea of what the data actually looked

like

and what you are trying to do. The 'bimonthly' for example, is

ambiguous in

English; do you mean every two months or twice a month?

Have a look at

https://github.com/hadley/devtools/wiki/Reproducibility

and

http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example

with special attention to dput() as a method of supplying sample data

to

the help list.

John Kane
Kingston ON Canada

-----Original Message-----
From: johnwasige at gmail.com
Sent: Sun, 5 Apr 2015 11:34:30 +0200
To: r-help at r-project.org
Subject: [R] Aggregating daily rainfall raster data to bimontly

data

Dear community,

I have daily rainfall raster data for 30 years (1982_2011). I

would like

to
aggregate daily to bimonthly raster data. Could somebody kindly

help on

how
to go about it!

Thanks for your help

--
John

      [[alternative HTML version deleted]]

friends

and family!

Visit http://www.inbox.com/photosharing to find out more!

      [[alternative HTML version deleted]]

Thanks Jim!

Do you have an idea on how I can go about getting bi-monthly (twice a
month) results for the month with 28, 29, 30 and 31 daily observations?

Thanks for your help

On Apr 5, 2015, at 2:40 PM, John Wasige wrote:

Thanks Jim!

Do you have an idea on how I can go about getting bi-monthly (twice a
month) results for the month with 28, 29, 30 and 31 daily observations?

Thanks for your help

raindate <- seq.Date(as.Date("1982-01-01"), as.Date("1983-01-01"),by=1)

 paste( format( head(raindate,30), "%Y"),
        cut(as.numeric(format( head(raindate,30),"%d")), c(0,16,32) ),
       sep="_")

 [1] "1982_(0,16]"  "1982_(0,16]"  "1982_(0,16]"  "1982_(0,16]"
 [5] "1982_(0,16]"  "1982_(0,16]"  "1982_(0,16]"  "1982_(0,16]"
 [9] "1982_(0,16]"  "1982_(0,16]"  "1982_(0,16]"  "1982_(0,16]"
[13] "1982_(0,16]"  "1982_(0,16]"  "1982_(0,16]"  "1982_(0,16]"
[17] "1982_(16,32]" "1982_(16,32]" "1982_(16,32]" "1982_(16,32]"
[21] "1982_(16,32]" "1982_(16,32]" "1982_(16,32]" "1982_(16,32]"
[25] "1982_(16,32]" "1982_(16,32]" "1982_(16,32]" "1982_(16,32]"
[29] "1982_(16,32]" "1982_(16,32]"

Another method would be to use `cut` on  as.POSIXlt(raindate)$mday

--
David.

John.

On Sun, Apr 5, 2015 at 11:25 PM, Jim Lemon <drjimlemon at gmail.com> wrote:

Hi John,
One way is to create an index variable that will divide your data into

the

appropriate intervals. There are a number of ways to do this. Say you

want

the "two month" version of bimonthly and you have a date variable
("raindate") for each observation like "1982-01-01".

date_order<-paste(rep(month.abb,30),rep(1982:2011,each=12),sep="")

month_index<-factor(format(as.Date(raindate,"%Y-%m-%d"),"%b%Y"),levels=date_order)

You can then subset the raster matrices by "month_index" and average

them

for each group

Jim

On Mon, Apr 6, 2015 at 3:08 AM, Jeff Newmiller <

jdnewmil at dcn.davis.ca.us>

wrote:

Please stop posting using HTML (as the Posting Guide warns you), and
follow John Kane's advice. Your reply below is not helping us

understand as

well as you seem to think it should.

---------------------------------------------------------------------------

Jeff Newmiller                        The     .....       .....  Go
Live...
DCN:<jdnewmil at dcn.davis.ca.us>        Basics: ##.#.       ##.#.  Live
Go...
                                     Live:   OO#.. Dead: OO#..  Playing
Research Engineer (Solar/Batteries            O.O#.       #.O#.  with
/Software/Embedded Controllers)               .OO#.       .OO#.
rocks...1k

---------------------------------------------------------------------------

Sent from my phone. Please excuse my brevity.

On April 5, 2015 9:52:18 AM PDT, John Wasige <johnwasige at gmail.com>
wrote:

Thanks Bert,

The structure of the data is a raster stack with nraw=867, Ncol=995

Rgds John


On Sun, Apr 5, 2015 at 6:39 PM, Bert Gunter <gunter.berton at gene.com>
wrote:

See ?tapply

However, as John said, without knowing the structure of your data, it
is impossible to provide a guaranteed recipe. For example, does the
data structure contain date information? -- it would be difficult

(but

not impossible depending on data structure) to aggregate by calendar
(bi-monthly, depending on your meaning of "bi") without knowing the
months. Aggregating by every n days would be easy, but that's

probably

not what you want.

Cheers,
Bert

Bert Gunter
Genentech Nonclinical Biostatistics
(650) 467-7374

"Data is not information. Information is not knowledge. And knowledge
is certainly not wisdom."
Clifford Stoll




On Sun, Apr 5, 2015 at 9:13 AM, John Kane <jrkrideau at inbox.com>

wrote:

Someone might if they had any idea of what the data actually looked

like

and what you are trying to do. The 'bimonthly' for example, is

ambiguous in

English; do you mean every two months or twice a month?

Have a look at

https://github.com/hadley/devtools/wiki/Reproducibility

and

http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example

with special attention to dput() as a method of supplying sample data

to

the help list.

John Kane
Kingston ON Canada

-----Original Message-----
From: johnwasige at gmail.com
Sent: Sun, 5 Apr 2015 11:34:30 +0200
To: r-help at r-project.org
Subject: [R] Aggregating daily rainfall raster data to bimontly

data

Dear community,

I have daily rainfall raster data for 30 years (1982_2011). I

would like

to
aggregate daily to bimonthly raster data. Could somebody kindly

help on

how
to go about it!

Thanks for your help

--
John

     [[alternative HTML version deleted]]

friends

and family!

Visit http://www.inbox.com/photosharing to find out more!

     [[alternative HTML version deleted]]

      [[alternative HTML version deleted]]