Hi Dan,
I similarly struggled when I first started and also use J to work with flat
files.
Here are some examples of different ways of working with the data:
load 'tables/csv'
t=. readcsv '/temp/Master.csv'
cols=. {.t NB. head of t
data=. }. t NB. behead t
colIdx=: cols i. ] NB. i. finds the
first
names=. (colIdx <'nameFirst') {"1 data NB. {"1 looks up by col index
(e.g. 16{"1 data)
joes=.((<'Joe') ([: I. =) names) { data NB. [: I = finds all indices
and then grab the rows
]numjoes=. # joes
398
freq=:({.;#)/.~
nameFrequency=.freq names NB. Don't unbox names,
otherwise it pads to the longest and makes it difficult to search
2{. nameFrequency
┌────────┬──┐
│┌────┐ │58│
││Hank│ │ │
│└────┘ │ │
├────────┼──┤
│┌──────┐│4 │
││Tommie││ │
│└──────┘│ │
└────────┴──┘
]uniqueNameCount=.# nameFrequency
2209
]joeCount=. ((>0{"1 nameFrequency) i. <'Joe') { nameFrequency NB. find Joe
in frequency table
┌─────┬───┐
│┌───┐│398│
││Joe││ │
│└───┘│ │
└─────┴───┘
On Mon, Oct 7, 2013 at 8:56 PM, Dan Bron <[email protected]> wrote:
> You mean " 'data' is plural " .
>
> -Dan
>
> PS: http://en.m.wikipedia.org/wiki/Muphry's_law
>
> (Yes, that link is spelled correctly :)
>
> Please excuse typos; composed on a handheld device.
>
> On Oct 7, 2013, at 8:00 PM, Eldon Eller <[email protected]> wrote:
>
> > Data are plural.
> >
> > On 10/07/2013 02:04 PM, Dan Bron wrote:
> >> Ganesh Rapolu
> >>> Because the data is boxed, all comparisons must be boxed.
> >> This was very well put (one short sentence which both clarifies the
> problem
> >> and justifies the solution).
> >>
> >> -Dan
> >>
> >>
> >>
> >> ----------------------------------------------------------------------
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