Use If rather than DoWhile.
u^:v y
means execute u if v is true.
PrintReport ^: (0<#) report_data_structures
Henry Rich
On 1/20/2014 12:48 PM, Devon McCormick wrote:
I won't use this as an example for this talk. If I do elaborate on matrix
multiplication, I usually like to emphasize how this is a specific instance
of a more general concept.
The problem I'm having now is that I'd like to use the power conjunction as
my example but I'm placing it in a hierarchy like this:
J Parts of Speech: a Functional Hierarchy
Name Argument Type Example?
Conjunction Verbs
Adverb Verbs and nouns
Verb Nouns
Noun -
but I have not been able to come up with a good, simple example of the
power conjunction using a couple of verbs. The best I have so far is from
Roger's essay: "Do While" using power conjunction:
http://www.jsoftware.com/jwiki/Essays/Do%20While . He uses this example -
which is pretty good for my purposes:
(1+3*])^:(1e5&>)^:_]3
but does not resonate as some kind of well-known problem. I wanted to do
something like this (to find the first Fibonacci number greater than 4e6):
fib^:(4e6&>)^:_]1
but I end up writing it like this:
(([: >: {.) , [: (fib) {.)^:(4000000 > {:)^:_]1
35 5702887
(so the 34th term is the one I'm looking for) but this involves too many
symbols I have not yet introduced or are otherwise unfamiliar.
Anyway, I have to finish this up in the next few hours so I can start
practicing it.
On Mon, Jan 20, 2014 at 12:51 AM, Henry Rich <henryhr...@nc.rr.com> wrote:
If you use this as an example, be sure you can explain how +/ . *, which
is usually matrix multiplication, applies to these operands which are not
matrices. Mathematically it would be an error to matrix-multiply two
vectors of the same shape.
Henry Rich
On 1/20/2014 12:14 AM, Devon McCormick wrote:
NB. Weighted mean:
1 10 1 ((+/ . *) % ([:+/[)) 10 2 30
5
On Thu, Jan 16, 2014 at 8:09 PM, Roger Hui <rogerhui.can...@gmail.com>
wrote:
The put down was for not so much that our system was not capable of
sensitivity analysis, or perhaps that we did not even know what
sensitivity
analysis was, but that we were unwilling to admit it.
-----------
The braggart claims to have Superman's powers.
"Can you crush things like Superman?"
The braggart took a walnut in each hand, absolutely crushed them to a
pulp,
and said, "Yes, I can."
"Can you see far away like Superman?"
The braggart flipped down a pair of binocular glasses he was wearing and
read out the words on the sign at the end of the block, and said, "Yes I
can."
"Can you fly like Superman?"
The braggart walked up to the roof of a 3-floor building, and jumped off
with a flying leap! Splat! With great struggle and lots of moaning, he
raised himself up on his elbows, and said, "Yessssh, yesh, ... yesh I
can."
On Thu, Jan 16, 2014 at 2:16 PM, Dan Bron <j...@bron.us> wrote:
I don't get the put-down (or joke). Can you explain it to me?
-Dan
----- Original Message ---------------
Subject: Re: [Jprogramming] more fork examples
From: Roger Hui <rogerhui.can...@gmail.com>
Date: Thu, 16 Jan 2014 13:14:12 -0800
To: Programming forum <programm...@jsoftware.com>
Thanks for the compliment but what I really need are for y'all to send
me
quotes/anecdotes not yet in the list. For example:
Once, in the early 1980s, Ken Iverson visited us in Calgary. Fred
Appleyard and I proudly showed off our system implemented in direct
definition. Ken asked a question which is essentially, "Can you do
sensitivity analysis?" We start mumbling something. Ken says, "Can you
touch your shoulder?", and proceeded to reach behind his neck to touch
the
opposite shoulder. I have yet to recover from this put-down :-).
BTW, among the APL crowd, accusing somebody of "mumbling something" is
done
by putting your hand in front of your mouth and muttering, "but ah eh
blah
blah ...".
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