setdiff
returns elements that are in a set but not in another one.
Syntax
v = setdiff(a, b) v = setdiff(a, b, orien) [v, ka] = setdiff(..)
Arguments
- a
a set of elements
- b
elements to remove from
a
.- orien
- oriented processing:
"r"
: rows ofa
are searched amongb
ones."c"
: columns ofa
are searched amongb
ones.- no orien: elements of
a
are searched amongb
ones.
- v
- Array with
a
's data type and encoding:- sorted vector of
a
's components that are not inb
. orien="r"
: matrix of rows ofa
that are not inb
, sorted in lexicographic order.orien="c"
: matrix of columns ofa
that are not inb
, sorted in lexicographic order.
- sorted vector of
- ka
vector of linear indices of selected
a
's components, rows, or columns, such thatv = a(ka)
, orv = a(ka,:)
(orien="r"
), orv = a(:,ka)
(orien="c"
)
If the option orien="r"
is used, a
and b
must have the same number of columns.
If the orien="c"
is used, they must have the same
number of rows.
Description
setdiff(a, b,..)
computes and returns the elements or rows or columns
of a
that are not in b
.
All duplicates (elements or rows or columns) are removed from a
and
from b
before processing.
Both a
and b
must have the same
data type (and integer type), but may mix dense and sparse encoding.
It can be vectors, matrices or hypermatrices of real or complex numbers, encoded integers, booleans, or strings. Sparse-encoded inputs are also accepted.
If a
is an hypermatrix and the "r"
option is used,
a
is replaced with the matrix of all its rows over all its higher
dimensions, before processing.
Same thing if b
is an hypermatrix.
If the "c"
option is used, a
or/and
"b"
are replaced with the respective matrices of all their columns.
The format of results is presented in the following table, according to the shape of
a
and the orien
option. In all cases, if all
entities of a
are in b
,
[]
is returned for v
as for ka
:
orien → | none | "r" | "c" | |||
---|---|---|---|---|---|---|
a ↓ | v | ka | v | ka | v | ka |
row | row | row | row | scal | row | row |
column | col | col | col | col | col | scal |
matrix | col | col | mat | col | mat | row |
hypermatrix | col | col | mat | col | mat | row |
scalar | scal | scal | scal | scal | scal | scal |
v
and ka
become empty
if a
is empty (whatever is b
), or if all
a
elements are in b
.
For booleans, setdiff(…)
is useful mainly with the "r" or "c" options.
Examples
Example #1:
--> a = grand(1, 10,"uin", 0, 9) a = 2. 2. 4. 5. 4. 1. 9. 5. 8. 3. --> b = grand(2, 4, "uin", 0, 9) b = 5. 0. 9. 9. 5. 6. 0. 4. --> [d, k] = setdiff(a, b); --> d, k d = 1. 2. 3. 8. k = 6. 1. 10. 9.
Example #2: column-wise processing
--> a = grand(2, 7,"uin", 0, 3) a = 0. 1. 0. 2. 3. 0. 2. 2. 2. 2. 1. 0. 1. 2. --> b = grand(2, 10, "uin", 0, 3) b = 1. 1. 3. 1. 1. 1. 3. 0. 2. 0. 3. 3. 2. 2. 0. 0. 1. 0. 1. 0. --> [d, k] = setdiff(a, b, "c"); --> d, k d = 0. 0. 2. 3. 1. 2. 2. 0. k = 6. 1. 7. 5.
Example #3: with some text
v1 = tokens("ab ca ba bb ca cb ba aa cc bc ac aa")' v2 = tokens("cc ac ca bb ac bc ab")' [r, k] = setdiff(v1, v2); r, k
--> v1 = tokens("ab ca ba bb ca cb ba aa cc bc ac aa")' v1 = !ab ca ac bb ca cb ba aa cc bc ac aa ! --> v2 = tokens("cc ac ca bb ac bc ab")' v2 = !cc ac ca bb ac bc ab ! --> [r, k] = setdiff(v1, v2); --> r, k r = !aa ba cb ! k = 8. 3. 6.
See also
- unique — ベクトルまたは行列のユニークなな要素を展開
- union — ベクトルの和集合要素を展開
- members — 配列の各要素または他の配列の行または列を数える(及び位置を調べる)
- vectorfind — locates occurences of a (wildcarded) vector in a matrix or hypermatrix
History
バージョン | 記述 |
< 5.0 | Function introduced. |
6.0.2 | Option "r" | "c" added, including for hypermatrices. |
6.1.0 | Extension to complex numbers. |
6.1.1 | Boolean inputs and sparse inputs (boolean or numeric) are now accepted. |
Report an issue | ||
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