An example:
x=:3 3 $i.9
y=:x+10
q=:2|x
x
0 1 2
3 4 5
6 7 8
y
10 11 12
13 14 15
16 17 18
q
0 1 0
1 0 1
0 1 0
q {"0 1 x,"0 y
0 11 2
13 4 15
6 17 8
/Erling
On 2014-07-07 19:53, Erling Hellenäs wrote:
It's obviously not possible to do any amendments in tacit code? It is
also less elegant to pass these three parameters in the two arguments
in tacit code? Any opinions about the use of From to do the same thing?
NB. x and y are arrays of the same rank
NB. q is a boolean, also of this rank
NB. The expression merges x and y.
NB. Where q is TRUE it picks from y, otherwise x
NB. q {"0 1 x,"0 y
If q is a vector and if we actually have a variable z of rank
(+/q),}.$y we can easily create x from q#^:_1 [ z ? No use for any
indexes?
/Erling
On 2014-07-07 12:33, Raul Miller wrote:
Another approach for this is:
(x*-.q)+y*q
Sadly, that only works when x and y are numeric. Boxes and literals do
not have zero and 1 values (hypothetically "fill" could be zero, but
"1" is harder to rationalize.)
A variant which uses amend might be:
(q#y) (I.q)} x
This only works when x and y are rank 1, but you could also use
something like this for higher ranked arrays:
($q)$ (q#&,y) (I.,q)} ,x
(I hope I didn't make too many mistakes this time. I'm running without
any corrective support.)
Thanks,
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