It could also be a simple verb.
f=: 13 :'(,:x)];.0 y'
f
] ];.0~ [: ,: [
3 4 f 'abcdefghijk'
Defg
Linda
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Don Guinn
Sent: Thursday, April 10, 2014 6:46 PM
To: Programming forum
Subject: Re: [Jprogramming] "Segmented Strings"
Sounds like you can format the data as you want once you get it all. Given
the amount of data there is no way to read it
the entire file
in an interactive environment. So it has to be indexed or in a database.
If you really want to use a segmented string you could keep the index to
the start of each line to
quickly get
the line. Also, build a hash for the keys you intend to search on rather
than trying to search the actual file.
This index and hash should fit in memory quite easily.
When you talk about a file that big, mapped or not, it's still going to
require the amount of virtual storage the size of the file, which will need
to be moved from the file or swap into real storage to process.
Scanning the entire file
will be very slow unless you have lots and lots of real memory.
I haven't seen anyone mention an easy way to substring from a text file. It
took me a long time to find it in the dictionary.
It really exists.
And it was not obvious when I finally did find it. So I will post it here
for anyone who hasn't found it.
substr=:4 : 0 NB. x: start and length, y: string
(,:x)];.0 y
)
3 4 substr 'abcdefghijk'
defg
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