select

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Conditional merge of selected elements of two vectors and/or scalars.

Usage
select(x, t, yl, yh)
x
condition vector; must be a vector!
t
threshold
yl
result if x[i] ≤ t{[i]}
yh
result if x[i] > t{[i]}
Note: t, yl and yh must be numbers or vectors with the same length as x
Result
A vector r with ...
r[i] = yl{[i]} if x[i] ≤ t{[i]} and
r[i] = yh{[i]} if x[i] > t{[i]}
The result r has the same length as x.
See also
vsubc, limit, limitlow, limithigh

<function list>

Example:

#a := eval vv(1,2,3,4,5,4,3,2,1)
#b := eval fill(9,0,1)
#c := eval select($#a,3,0,$#a)
// -> $#c = { 0 , 0 , 0 , 4 , 5 , 4 , 0 , 0 , 0 } 
#d := eval select($#a, $#b , $#b , $#a)
// -> $#d = { 1 , 2 , 3 , 4 , 5 , 5 , 6 , 7 , 8 }
#e := eval select($#b%2, 0, $#b, -1)
// -> $#d = { 0 , -1 , 2 , -1 , 4 , -1 , 6 , -1 , 8 }