Thanks for this cool discussion.
I will add this to the NepCSV chapter :)
On 14/11/14 21:00, Sven Van Caekenberghe wrote:
This is what I tried:
'paul.csv' asFileReference writeStreamDo: [ :file|
ZnBufferedWriteStream on: file do: [ :out |
(NeoCSVWriter on: out) in: [ :writer |
writer writeHeader: { #Number. #Color. #Integer. #Boolean}.
1 to: 1e7 do: [ :each |
writer nextPut: { each. #(Red Green Blue) atRandom. 1e6 atRandom.
#(true false) atRandom } ] ] ] ].
This results in a 300Mb file:
$ ls -lah paul.csv
-rw-r--r--@ 1 sven staff 327M Nov 14 20:45 paul.csv
$ wc paul.csv
10000001 10000001 342781577 paul.csv
This is a selective read and collect (loads about 10K records):
Array streamContents: [ :out |
'paul.csv' asFileReference readStreamDo: [ :in |
(NeoCSVReader on: (ZnBufferedReadStream on: in)) in: [ :reader |
reader skipHeader; addIntegerField; addSymbolField; addIntegerField;
addFieldConverter: [ :x | x = #true ].
reader do: [ :each | each third < 1000 ifTrue: [ out nextPut: each ] ] ]
] ].
