?"row by row processing"

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1

Hello,

If I have a table -

a b c

1 2 3
6 4 2
5 5 1

How do I do something like this –

update myval: $[a<=b;[a];[c]] from

I want result like –

a b c myval

1 2 3 1
6 4 2 2
5 5 1 1

Thanks in Advance,
Ramdas

2

update myval:(c*a>=b)+(a*a<b) from <table>?

2009/11/13 Ramdas <rthatte@gmail.com>

Hello,

If I have a table -

a ? b ? c

1 ? 2 ? 3
6 ? 4 ? 2
5 ? 5 ? 1

How do I do something like this –

update myval: $[a<=b;[a];[c]] from <table>

I want result like –

a ? ?b ? ?c ? ?myval

1 ? ?2 ? ?3 ? ?1
6 ? ?4 ? ?2 ? ?2
5 ? ?5 ? ?1 ? ?1

Thanks in Advance,
Ramdas

3

vector conditional

?[condition;true;false]

e.g.

update myval: ?[a<=b;a;c] from <table>

4

And if you need to apply a function to each row you can use the each-both adverb '.

q)table:( a:1 6 5; b:2 4 5; c:3 2 1)
q)update myval:{$[x<y;x;z]}'[a;b;c] from table
a b c myval

1 2 3 1
6 4 2 2
5 5 1 1

In your case though, I would go with the vector conditional since that is much faster.

q)table:( a:1000?100; b:1000?100; c:1000?100)
q)\t do[10000;update myval:{$[x<y;x;z]}'[a;b;c] from table;]
2561
q)\t do[10000;update myval:?[a<b;a;c] from table;]
114

5

Thanks guys,Vector condition worked well.–RamdasOn Nov 13, 6:27?pm, Daniel Br?ndstr?m <daniel.brandst…>wrote:> And if you need to apply a function to each row you can use the each-both> adverb '.>> q)table:( a:1 6 5; b:2 4 5; c:3 2 1)> q)update myval:{$[x a b c myval> -----------> 1 2 3 1> 6 4 2 2> 5 5 1 1>> In your case though, I would go with the vector conditional since that is> much faster.>> q)table:( a:1000?100; b:1000?100; c:1000?100)> q)\t do[10000;update myval:{$[x 2561> q)\t do[10000;update myval:?[a 114>>>>>> On Fri, Nov 13, 2009 at 8:22 PM, Charles Skelton <char…> wrote:> > vector conditional>> > ?[condition;true;false]>> > e.g.>> > update myval: ?[a<=b;a;c] from

>> > On Fri, Nov 13, 2009 at 7:43 PM, Ramdas <rtha…> wrote:>> >> Hello,>> >> If I have a table ->> >> a ? b ? c> >> ------------> >> 1 ? 2 ? 3> >> 6 ? 4 ? 2> >> 5 ? 5 ? 1>> >> How do I do something like this –>> >> update myval: $[a<=b;[a];[c]] from
>> >> I want result like –>> >> a ? ?b ? ?c ? ?myval> >> ----------------------------> >> 1 ? ?2 ? ?3 ? ?1> >> 6 ? ?4 ? ?2 ? ?2> >> 5 ? ?5 ? ?1 ? ?1>> >> Thanks in Advance,> >> Ramdas>> –> Hey! It compiles! Ship it!> — Hide quoted text ->> - Show quoted text -
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