Smalltalk › Pharo › Pharo Smalltalk Users

little "challenge"

_‹ Previous Topic Next Topic _›

Classic

List

Threaded

14 messages Options

Stephane Ducasse-3

little "challenge"

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)

{ #(17 17 16 18 17 18 19) . #(19 19 18 19 19 20 19) . #(20 19 20 20 20 19 20)}

any code?

Sven Van Caekenberghe-2

Re: little "challenge"

The first thing I found:

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20) groupsOf: 7 atATimeCollect: [ :x | x ]

"#(#(16 17 17 16 18 17 18) #(19 19 19 18 19 19 20) #(19 20 19 20 20 20 19))"

> On 25 Apr 2017, at 22:08, Stephane Ducasse <[hidden email]> wrote:
>
> #(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)
>
> ->
>
> { #(17 17 16 18 17 18 19) . #(19 19 18 19 19 20 19) . #(20 19 20 20 20 19 20)}
>
> any code?

nacho

Re: little "challenge"

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20) allButFirst groupsOf: 7 atATimeCollect: [ :element | element ].

Nacho Smalltalker apprentice. Buenos Aires, Argentina.

Richard Sargent (again)

Re: little "challenge"

In reply to this post by Stephane Ducasse-3

In 2003, I implemented the following method. It is something that comes up from time to time.

!SequenceableCollection publicMethods !

splitEvery: chunkSize
"Answer a collection of sub-collections each of the specified chunk size.
If the receiver size is not a multiple of chunkSize, the last sub-collection will be shorter."

| chunks stream |
chunkSize < 1 ifTrue: [ ^self splitEvery: 1 ].

stream := ReadStream on: self.
chunks := OrderedCollection new.
[stream atEnd] whileFalse: [
chunks add: (stream nextOrLess: chunkSize).
].

^chunks.
! !

From: Pharo-users [mailto:[hidden email]] On Behalf Of Stephane Ducasse
Sent: April 25, 2017 13:08
To: Any question about pharo is welcome
Subject: [Pharo-users] little "challenge"

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)

{ #(17 17 16 18 17 18 19) . #(19 19 18 19 19 20 19) . #(20 19 20 20 20 19 20)}

any code?

Stephane Ducasse-3

Re: little "challenge"

In reply to this post by Sven Van Caekenberghe-2

I did not know this one :)

tx sven

On Tue, Apr 25, 2017 at 10:26 PM, Sven Van Caekenberghe <[hidden email]> wrote:

The first thing I found:

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20) groupsOf: 7 atATimeCollect: [ :x | x ]

"#(#(16 17 17 16 18 17 18) #(19 19 19 18 19 19 20) #(19 20 19 20 20 20 19))"

> On 25 Apr 2017, at 22:08, Stephane Ducasse <[hidden email]> wrote:
>
> #(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)
>
> ->
>
> { #(17 17 16 18 17 18 19) . #(19 19 18 19 19 20 19) . #(20 19 20 20 20 19 20)}
>
> any code?

Stephane Ducasse-3

Re: little "challenge"

In reply to this post by nacho

Tx same comments!

On Tue, Apr 25, 2017 at 10:48 PM, nacho <[hidden email]> wrote:

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)
allButFirst groupsOf: 7 atATimeCollect: [ :element | element ].

-----
Nacho
Smalltalker apprentice.
Buenos Aires, Argentina.
--
View this message in context: http://forum.world.st/little-challenge-tp4944073p4944079.html
Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

Stephane Ducasse-3

Re: little "challenge"

In reply to this post by Richard Sargent (again)

This is fun because my method was called splitEvery: too :)

On Wed, Apr 26, 2017 at 6:19 AM, Richard Sargent <[hidden email]> wrote:

In 2003, I implemented the following method. It is something that comes up from time to time.

!SequenceableCollection publicMethods !

splitEvery: chunkSize
"Answer a collection of sub-collections each of the specified chunk size.
If the receiver size is not a multiple of chunkSize, the last sub-collection will be shorter."

| chunks stream |
chunkSize < 1 ifTrue: [ ^self splitEvery: 1 ].

stream := ReadStream on: self.
chunks := OrderedCollection new.
[stream atEnd] whileFalse: [
chunks add: (stream nextOrLess: chunkSize).
].

^chunks.
! !

From: Pharo-users [mailto:[hidden email]] On Behalf Of Stephane Ducasse
Sent: April 25, 2017 13:08
To: Any question about pharo is welcome
Subject: [Pharo-users] little "challenge"

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)

->

{ #(17 17 16 18 17 18 19) . #(19 19 18 19 19 20 19) . #(20 19 20 20 20 19 20)}

any code?

Stephane Ducasse-3

Re: little "challenge"

In reply to this post by Richard Sargent (again)

we do not have nextOrLess: in Pharo.

On Wed, Apr 26, 2017 at 6:19 AM, Richard Sargent <[hidden email]> wrote:

In 2003, I implemented the following method. It is something that comes up from time to time.

!SequenceableCollection publicMethods !

splitEvery: chunkSize
"Answer a collection of sub-collections each of the specified chunk size.
If the receiver size is not a multiple of chunkSize, the last sub-collection will be shorter."

| chunks stream |
chunkSize < 1 ifTrue: [ ^self splitEvery: 1 ].

stream := ReadStream on: self.
chunks := OrderedCollection new.
[stream atEnd] whileFalse: [
chunks add: (stream nextOrLess: chunkSize).
].

^chunks.
! !

From: Pharo-users [mailto:[hidden email]] On Behalf Of Stephane Ducasse
Sent: April 25, 2017 13:08
To: Any question about pharo is welcome
Subject: [Pharo-users] little "challenge"

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)

->

{ #(17 17 16 18 17 18 19) . #(19 19 18 19 19 20 19) . #(20 19 20 20 20 19 20)}

any code?

Richard Sargent (again)

Re: little "challenge"

Sorry, Stephane. Feel free to implement missing methods (or their equivalent).

:-)

On Apr 25, 2017, at 23:39, Stephane Ducasse <[hidden email]> wrote:

we do not have nextOrLess: in Pharo.

On Wed, Apr 26, 2017 at 6:19 AM, Richard Sargent <[hidden email]> wrote:

In 2003, I implemented the following method. It is something that comes up from time to time.

!SequenceableCollection publicMethods !

splitEvery: chunkSize
"Answer a collection of sub-collections each of the specified chunk size.
If the receiver size is not a multiple of chunkSize, the last sub-collection will be shorter."

| chunks stream |
chunkSize < 1 ifTrue: [ ^self splitEvery: 1 ].

stream := ReadStream on: self.
chunks := OrderedCollection new.
[stream atEnd] whileFalse: [
chunks add: (stream nextOrLess: chunkSize).
].

^chunks.
! !

From: Pharo-users [mailto:[hidden email]] On Behalf Of Stephane Ducasse
Sent: April 25, 2017 13:08
To: Any question about pharo is welcome
Subject: [Pharo-users] little "challenge"

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)

->

{ #(17 17 16 18 17 18 19) . #(19 19 18 19 19 20 19) . #(20 19 20 20 20 19 20)}

any code?

philippeback

Re: little "challenge"

In reply to this post by Stephane Ducasse-3

Doesn't matter as next returns if there is less than required.

groups := OrderedCollection new.

input := (String loremIpsum: 20).

input readStream in: [ :s | [s atEnd] whileFalse: [ groups add: (s next: 7) ]].

groups.

Interestingly loremIpsum: adds Character cr to from paragraphs (output looked strange at first glance).

Phil

On Wed, Apr 26, 2017 at 8:38 AM, Stephane Ducasse <[hidden email]> wrote:

we do not have nextOrLess: in Pharo.

On Wed, Apr 26, 2017 at 6:19 AM, Richard Sargent <[hidden email]> wrote:

In 2003, I implemented the following method. It is something that comes up from time to time.

!SequenceableCollection publicMethods !

splitEvery: chunkSize
"Answer a collection of sub-collections each of the specified chunk size.
If the receiver size is not a multiple of chunkSize, the last sub-collection will be shorter."

| chunks stream |
chunkSize < 1 ifTrue: [ ^self splitEvery: 1 ].

stream := ReadStream on: self.
chunks := OrderedCollection new.
[stream atEnd] whileFalse: [
chunks add: (stream nextOrLess: chunkSize).
].

^chunks.
! !

From: Pharo-users [mailto:[hidden email]] On Behalf Of Stephane Ducasse
Sent: April 25, 2017 13:08
To: Any question about pharo is welcome
Subject: [Pharo-users] little "challenge"

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)

->

{ #(17 17 16 18 17 18 19) . #(19 19 18 19 19 20 19) . #(20 19 20 20 20 19 20)}

any code?

philippeback

Re: little "challenge"

In reply to this post by Stephane Ducasse-3

I implemented it for fun and noticed that in your test data, the first 16 is gone. So, groupings are wrong with all methods proposed in a sense.

With Richard's version, we get this in Pharo

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20) splitEvery: 7

"an OrderedCollection(#(16 17 17 16 18 17 18) #(19 19 19 18 19 19 20) #(19 20 19 20 20 20 19) #(20))"

splitEvery: chunkSize

"Answer a collection of sub-collections each of the specified chunk size.

If the receiver size is not a multiple of chunkSize, the last sub-collection will be shorter."

| chunks stream |

chunkSize < 1 ifTrue: [ ^self splitEvery: 1 ].

stream := ReadStream on: self.

chunks := OrderedCollection new.

[stream atEnd] whileFalse: [

chunks add: (stream next: chunkSize).

^chunks.

Phil

On Wed, Apr 26, 2017 at 8:38 AM, Stephane Ducasse <[hidden email]> wrote:

we do not have nextOrLess: in Pharo.

On Wed, Apr 26, 2017 at 6:19 AM, Richard Sargent <[hidden email]> wrote:

In 2003, I implemented the following method. It is something that comes up from time to time.

!SequenceableCollection publicMethods !

splitEvery: chunkSize
"Answer a collection of sub-collections each of the specified chunk size.
If the receiver size is not a multiple of chunkSize, the last sub-collection will be shorter."

| chunks stream |
chunkSize < 1 ifTrue: [ ^self splitEvery: 1 ].

stream := ReadStream on: self.
chunks := OrderedCollection new.
[stream atEnd] whileFalse: [
chunks add: (stream nextOrLess: chunkSize).
].

^chunks.
! !

From: Pharo-users [mailto:[hidden email]] On Behalf Of Stephane Ducasse
Sent: April 25, 2017 13:08
To: Any question about pharo is welcome
Subject: [Pharo-users] little "challenge"

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)

->

{ #(17 17 16 18 17 18 19) . #(19 19 18 19 19 20 19) . #(20 19 20 20 20 19 20)}

any code?

Stephane Ducasse-3

Re: little "challenge"

In reply to this post by Stephane Ducasse-3

Now I fully got the implementation

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20) groupsOf: 7 atATimeCollect: [ :x | x ]

>>> #(#(16 17 17 16 18 17 18) #(19 19 19 18 19 19 20) #(19 20 19 20 20 20 19))

#(1 1 1 10 10 10 100 100 100)

groupsOf: 3 atATimeCollect: [ :x :y :z | x + y + z]

>>> #(3 30 300)

#(1 1 1 10 10 10 100 100 100)

groupsOf: 3 atATimeCollect: [ :x | x ]

>>> #(#(1 1 1) #(10 10 10) #(100 100 100))

On Wed, Apr 26, 2017 at 8:38 AM, Stephane Ducasse <[hidden email]> wrote:

we do not have nextOrLess: in Pharo.

On Wed, Apr 26, 2017 at 6:19 AM, Richard Sargent <[hidden email]> wrote:

In 2003, I implemented the following method. It is something that comes up from time to time.

!SequenceableCollection publicMethods !

splitEvery: chunkSize
"Answer a collection of sub-collections each of the specified chunk size.
If the receiver size is not a multiple of chunkSize, the last sub-collection will be shorter."

| chunks stream |
chunkSize < 1 ifTrue: [ ^self splitEvery: 1 ].

stream := ReadStream on: self.
chunks := OrderedCollection new.
[stream atEnd] whileFalse: [
chunks add: (stream nextOrLess: chunkSize).
].

^chunks.
! !

From: Pharo-users [mailto:[hidden email]] On Behalf Of Stephane Ducasse
Sent: April 25, 2017 13:08
To: Any question about pharo is welcome
Subject: [Pharo-users] little "challenge"

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)

->

{ #(17 17 16 18 17 18 19) . #(19 19 18 19 19 20 19) . #(20 19 20 20 20 19 20)}

any code?

philippeback

Re: little "challenge"

So the last 20 is left out.

Correct?

Phil

On Wed, Apr 26, 2017 at 11:20 AM, Stephane Ducasse <[hidden email]> wrote:

Now I fully got the implementation

"
#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20) groupsOf: 7 atATimeCollect: [ :x | x ]
>>> #(#(16 17 17 16 18 17 18) #(19 19 19 18 19 19 20) #(19 20 19 20 20 20 19))
"
"
#(1 1 1 10 10 10 100 100 100)
groupsOf: 3 atATimeCollect: [ :x :y :z | x + y + z]
>>> #(3 30 300)
"

"
#(1 1 1 10 10 10 100 100 100)
groupsOf: 3 atATimeCollect: [ :x | x ]
>>> #(#(1 1 1) #(10 10 10) #(100 100 100))
"

On Wed, Apr 26, 2017 at 8:38 AM, Stephane Ducasse <[hidden email]> wrote:
we do not have nextOrLess: in Pharo.

On Wed, Apr 26, 2017 at 6:19 AM, Richard Sargent <[hidden email]> wrote:

In 2003, I implemented the following method. It is something that comes up from time to time.

!SequenceableCollection publicMethods !

splitEvery: chunkSize
"Answer a collection of sub-collections each of the specified chunk size.
If the receiver size is not a multiple of chunkSize, the last sub-collection will be shorter."

| chunks stream |
chunkSize < 1 ifTrue: [ ^self splitEvery: 1 ].

stream := ReadStream on: self.
chunks := OrderedCollection new.
[stream atEnd] whileFalse: [
chunks add: (stream nextOrLess: chunkSize).
].

^chunks.
! !

From: Pharo-users [mailto:[hidden email]] On Behalf Of Stephane Ducasse
Sent: April 25, 2017 13:08
To: Any question about pharo is welcome
Subject: [Pharo-users] little "challenge"

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)

->

{ #(17 17 16 18 17 18 19) . #(19 19 18 19 19 20 19) . #(20 19 20 20 20 19 20)}

any code?

Stephane Ducasse-3

Re: little "challenge"

splitEvery: n

^ (n

to: self size

by: n)

collect: [:index |

(self copyFrom: index - n + 1 to: index)]

is my solution

On Wed, Apr 26, 2017 at 11:34 AM, [hidden email] <[hidden email]> wrote:

So the last 20 is left out.

Correct?

Phil

On Wed, Apr 26, 2017 at 11:20 AM, Stephane Ducasse <[hidden email]> wrote:
Now I fully got the implementation

"
#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20) groupsOf: 7 atATimeCollect: [ :x | x ]
>>> #(#(16 17 17 16 18 17 18) #(19 19 19 18 19 19 20) #(19 20 19 20 20 20 19))
"
"
#(1 1 1 10 10 10 100 100 100)
groupsOf: 3 atATimeCollect: [ :x :y :z | x + y + z]
>>> #(3 30 300)
"

"
#(1 1 1 10 10 10 100 100 100)
groupsOf: 3 atATimeCollect: [ :x | x ]
>>> #(#(1 1 1) #(10 10 10) #(100 100 100))
"

On Wed, Apr 26, 2017 at 8:38 AM, Stephane Ducasse <[hidden email]> wrote:
we do not have nextOrLess: in Pharo.

On Wed, Apr 26, 2017 at 6:19 AM, Richard Sargent <[hidden email]> wrote:

In 2003, I implemented the following method. It is something that comes up from time to time.

!SequenceableCollection publicMethods !

splitEvery: chunkSize
"Answer a collection of sub-collections each of the specified chunk size.
If the receiver size is not a multiple of chunkSize, the last sub-collection will be shorter."

| chunks stream |
chunkSize < 1 ifTrue: [ ^self splitEvery: 1 ].

stream := ReadStream on: self.
chunks := OrderedCollection new.
[stream atEnd] whileFalse: [
chunks add: (stream nextOrLess: chunkSize).
].

^chunks.
! !

From: Pharo-users [mailto:[hidden email]] On Behalf Of Stephane Ducasse
Sent: April 25, 2017 13:08
To: Any question about pharo is welcome
Subject: [Pharo-users] little "challenge"

#(16 17 17 16 18 17 18 19 19 19 18 19 19 20 19 20 19 20 20 20 19 20)

->

{ #(17 17 16 18 17 18 19) . #(19 19 18 19 19 20 19) . #(20 19 20 20 20 19 20)}

any code?