Something interesting about missing values and data-structure to
represent them like shadow matrix:
https://github.com/njtierney/naniar?utm_content=buffer26e7b
Some month ago, I build a Roassal viz in order to see missing values
in CSV file:
https://twitter.com/SergeStinckwich/status/705839378917167104
On Thu, Dec 22, 2016 at 9:34 AM, stepharong wrote:
>
>
> Yes I see. I will keep thinking about it.
>
>
> On Wed, 21 Dec 2016 20:58:26 +0100, Tudor Girba
> wrote:
>
>> Hi,
>>
>>> On Dec 21, 2016, at 3:05 PM, stepharong wrote:
>>>
>>>
>>>
Hi Alex,
Following the design proposed by Stef, in your case you would use a
different collection.
>>>
>>>
>>> Doru I have multiple missingValue so that they embed their own strategy.
>>> Now I do not know for the scenario of alex.
>>
>>
>> Yes, yes. And that is great.
>>
>> It seemed to me that Alex wanted to find from the collection the elements
>> that have a MissingValue, and for that he wants to use collect:. But, your
>> collection collect: ignores the MissingValue. That is why I thought that he
>> can serve his case with another collection type.
>>
>> Cheers,
>> Doru
>>
>>
Cheers,
Doru
> On Dec 21, 2016, at 8:13 AM, Alexandre Bergel
> wrote:
>
> Hi Stef,
>
> You are raising an interesting point to discuss. This MissingValue is
> indeed better than having -1
> Something to keep in mind: it may be that one would like to focus on
> the missing value and not really the value.
>
> Consider:
>
>> testCollect
>>
>> | uarray collected |
>> uarray := UniformOrderedCollection new.
>> uarray add: 10.
>> uarray add: 20.
>> uarray add: (MissingValue discarding).
>> collected := uarray collect: [ :each | each ].
>> self assert: collected size equals: 2.
>
>
> It could well be that I would like to be able to query over the
> MissingValue.
> Can something like possible: uarray collect: #isMissing
> ?
>
> Cheers,
> Alexandre
>
>
>> On Dec 20, 2016, at 10:15 PM, stepharong wrote:
>>
>> Hi dear great OO designers
>>
>> Here is a little challenges for your brainy souls :)
>>
>> In Moose when we compute metrics it may happen than a tool (often
>> external to pharo) does not compute a metrics
>> and when we request it in moose we check and often we return a not so
>> good -1.
>>
>> I'm trying to brainstorm on a solution
>>
>> - first may be the simplest way is to not invoke a metrics when it is
>> not computed. But it means that we should know it and that we should
>> have a
>> registration mechanism. After all this is probably the best solution.
>>
>> - Second we were thinking to use exception but when we have multiple
>> entities missing one metrics I have serious doubts.
>>
>> - Second I was thinking about having the following behavior
>>
>> testCollect
>>
>> | uarray collected |
>> uarray := UniformOrderedCollection new.
>> uarray add: 10.
>> uarray add: 20.
>> uarray add: (MissingValue discarding).
>> collected := uarray collect: [ :each | each ].
>> self assert: collected size equals: 2.
>>
>> testDo
>>
>> | res uarray |
>> uarray := UniformOrderedCollection new.
>> uarray add: 10.
>> uarray add: 20.
>> uarray add: (MissingValue discarding).
>> uarray add: 40.
>> res := 0.
>> uarray do: [ :each | res := res + each ].
>> self assert: res equals: 70.
>>
>>
>> testCollectDefaulting
>>
>> | uarray collected |
>> uarray := UniformOrderedCollection new.
>> uarray add: 10.
>> uarray add: 20.
>> uarray add: (MissingValue default: 33).
>> collected := uarray collect: [ :each | each ].
>> self assert: collected size equals: 3.
>> self assert: collected third equals: 33
>>
>>
>> I basically started to implement
>>
>>
>> do: aBlock
>> "Refer to the comment in Collection|do:."
>> 1 to: self size do:
>> [:index | (self at: index) toDo: aBlock on: self]
>>
>>
>>
>> collect: aBlock
>> "Evaluate aBlock with each of the receiver's elements as the
>> argument.
>> Collect the resulting values into a collection like the
>> receiver. Answer
>> the new collection."
>>
>> | newCollection |
>> newCollection := self species new.
>> self
>> do: [ :each | each toCollect: aBlock on: newCollection
>> ].
>> ^ newCollection
>>
>>
>> and
>>
>> Discard
