> On 28 Sep 2015, at 17:21, Nicolai Hess <[email protected]> wrote:
>
> Thanks Mariano, Sven
>
>
>
> 2015-09-28 16:42 GMT+02:00 Sven Van Caekenberghe <[email protected]>:
>
> > On 28 Sep 2015, at 15:04, Mariano Martinez Peck <[email protected]>
> > wrote:
> >
> > Imagine something like this:
> >
> > neoCSVReader := (NeoCSVReader on: stream).
> > neoCSVReader
> > separator: $,;
> > recordClass: PriceRecord;
> > addIgnoredField; "<name>"
> > addField: #securityUniqueId: ; "<ticker>"
> > addField: #date: converter: [ :string | Date readFrom: string
> > readStream pattern: 'yyyymmdd' ]; "<date>"
> > addFloatField: #open: ; "<open>"
> > addFloatField: #high: ; "<high>"
> > addFloatField: #low: ; "<low>"
> > addFloatField: #close: ; "<close>"
> > addIntegerField: #volume: . "<vol>"
> > neoCSVReader skipHeader.
> > priceRecords := neoCSVReader upToEnd.
> >
> >
> > The #recordClass: is optional. If not, you can get an array of arrays
> > instead.
> > You can add #addIgnoredField for all the ones you want to ignore, then add
> > the #addNumber: etc for the number ones, etc.
>
> Correct.
>
> But I have to call addIgnoredField ~ 25 times.
> I hope there were a way to specifiy column index and field descirption only
> for those columns I am interested in.
NeoCSVReader>>#addIgnoredFields: count
"Add a count of consecutive ignored fields to receiver."
;-)
>
> > To write a default empty value, I would use my own converter. Something
> > like:
> >
> > addField: #stringcolumn: converter: [ :string | string isEmptyOrNil ifTrue:
> > [ '' ] ];
> > addField: #numbercolumn: converter: [ :string | string isEmptyOrNil ifTrue:
> > [ 0 ] ifFalse: [ NeoNumberParser parse: string ] ];
>
> Yes this helps
>
>
> Actually there is NeoCSVReader>>#emptyFieldValue: which you can use the
> configure the reader (but it counts for all fields).
>
>
>
>
> > Hope this helps.
>
>
>
>
> >
> > Cheers,
> >
> >
> >
> > On Mon, Sep 28, 2015 at 9:06 AM, Nicolai Hess <[email protected]> wrote:
> > Hi,
> >
> > I have two problems I could not solve:
> >
> > 1. I would like to read only some columns: I have a large file with
> > ~30 colums, but I am only interested on ~5 columns
> > (not that important, I could pre-process the file) but anyway it would
> > be
> > nice to do it in smalltalk.
> >
> > 2. some columns will contain only strings (quoted values) and some only
> > numbers,
> > but the field may be empty, is it possible to define the default
> > "emptyValue" as an
> > - empty string for empty fields in the "string column"
> > - 0 for empty fields in the "number column"?
> >
> >
> > thanks
> > in advance
> >
> > nicolai
> >
> >
> >
> > --
> > Mariano
> > http://marianopeck.wordpress.com
