- Справка Scilab
- Ключевые слова Scilab
- обратный слэш (\)
- brackets [,;]
- знак равенства
- круглые скобки
- точка с запятой
- слэш (косая черта)
Concatenation. Recipients of an assignment. Results of a function
Mh = [m11 m12 m13.. m1N] or [m11, m12, m13,.., m1N] Mv = [m11 ; m21 ; m31..; mN1] M = [m11, m12,...; m21, m22,...;...] [r1, r2,...] = func(...) [r1, r2,.., rN] = (e1, e2, .., eN) [r1, r2,.., rk] = (e1, e2, .., ek,.., eN) [r1, r2,.., rN] = mylist(:) [r1, r2,.., rN] = S.field([i1 i2.. iN])
- m11, m12,...
Set of objects to be concatenated (and merged: the former individual containers are removed). The following subsets of types of objects can be mixed in-between, but are mutually exclusive:
- Matrices of booleans, reals, complex numbers, polynomials, rationals: The data type of the concatenated result is set by the rules defined below (see the type conversions rules).
- Matrices of encoded integers of any
Encoded integers of different inttypes can't be concatenated together.
- Arrays of structures with same fields. Fields may be in different orders from an array to other ones.
- Typed lists of type syslin.
- M, Mh, Mv
Matrices with the type of all
m##(if they all have the same data type)
- e1, e2,..
Input objects (literals like
"abcd", variables, or expressions like
a simple list
Array of Structures with a field named
- i1, i2,..
Indices of components selected from
- r1, r2,...
-  on right-hand side: concatenators
[..] bundle their contents of simple and compatible types into a homogeneous vector, matrix or hypermatrix.An horizontal or a vertical concatenation is a binary iterated operator. It is performed step-by-step from left-to-right, and from top-to-bottom. Thus,
[1 3 5 7]is performed as
[[[1 3] 5] 7].
- spaces (blanks or tabs) or commas are
used as columns separators.
Using commas instead of spaces is safer. For instance,
[2 1 +%i]means
[2, 1, %i], while
[2 1 + %i]means
- semi-colons or carriage-return are used
as rows separators. Multiple rows do not need
the continuation dots
In some limits, brackets may be applied on a set of data having different but compatible types. In this case, some data are converted into the dominating type available in the set. The main conversion rules are the following:
- boolean < decimal number < complex
- decimal number < polynomial < rational
booleans and polynomials are not compatible.
[%t 2. %z]is accepted:
[%t 2.]is first converted into
[1. 2.], and then
[[1. 2.] %z]is accepted.
[%z %t 2.]is rejected and yields an error. Indeed,
[%z %t]can't be converted first.
- The result becomes complex-encoded as soon as
a complex-encoded component -- value, polynomial,
or rational -- is met in the list
(even with a null imaginary part)
Similarly, the result becomes sparse-encoded as soon as a sparse-encoded component is met and processed.
- It is possible to concatenate polynomials or/and
rationals having different variable names. Then,
the first polynomial or rational met in the list
sets the variable name to the concatenation result:
[%z, 1+%s, 1-%i*%s] // => [z, 1+z, 1-iz].
- Any encoded integer can be concatenated
only with integers of the same inttype.
Thus, the expressions
[int8(2) 1.]will all yield an error.
- Text components can be concatenated
(in the set meaning, with brackets) only with other
text components or with the empty matrix.
- [,]: horizontal concatenation:
This operator is binary and automatically
iterated from left to right. Its overloading
- [;]: vertical concatenation:
This operator is binary and automatically
iterated from top to bottom. Its overloading
- spaces (blanks or tabs) or commas are used as columns separators.
-  on left-hand side of a
In this case, brackets are no longer concatenators. They are used as left and right delimiters of a series of variables used as recipients.
- Recipients must be variables. Litteral expressions are not accepted.
- Variables shall be separated with comas.
- In a distributive assignment, there must
be at most as many LHS recipients
as output sources, not more. If there are less
recipients on the left than sources on the right,
non-collected data sources are ignored. Examples :
[a,b]=(%pi,"Hi", %z)is OK, but
[a,b,c]=(%pi,"Hi")yields an error because
cexpects some foods.
- The same variable may be used several times
in the list. Then, multiple assignments are done from
right to left (!)
and overwrite the previous ones.
[a,b,a] = (%pi, %z, "Allo")is equivalent to
a = %pi, b = %z.
// Horizontal concatenations a = [ %pi 4 -1 ] b1 = grand(3,4,"uin",0,10) b2 = grand(3,2,"uin",0,10) b = [b1 b2] // they must have the same number of rows // Vertical concatenations a = [-2 ; 10 ; 7] b1 = grand(2,4,"uin",0,10) b2 = grand(3,4,"uin",0,10) b = [b1 ; b2] // they must have the same number of columns // Mixed horizontal and vertical concatenations a = [ 3 7 ; 6, 5 ] b = [ 1:3 ; 7:3:13] c = [ a b ; a b] d = [ 3 5 1 4 ] e = [ d d d d d d ] // Concatenation of various types of data: ['this is' ; 'a column' ; 'of texts'] s = poly(0,'s');[1/s,2/s] [tf2ss(1/s),tf2ss(2/s)] [%t %f %f %T %F] // Heterogeneous concatenations with automatical types conversions [%T %pi %f 2] [%pi, 2+%i, %F] v = [%pi+0*%i, %F, %z, (1-%z)^2 ]; typeof(v), isreal(v) v = [10 1/%z], typeof(v) // Incompatible heterogeneous concatenations => ERRORS [%F %z] [%F int8(5)] [int8(%pi) uint8(%e)] [int8(%pi) int16(%e)]
// Output from a function. Most often, output results are serially optional: M = rand(3,3); [u, s] = schur(M) // we expect and use both results u and s u = schur(M) // we expect and store only the first result u // Direct RHS list [a, b, c] = (%pi, %t, "test") [a, b] = (%e, %f, "Hello") [a, b, a] = (%pi, %t, "test"); // Explicit RHS list L = list(%z, %i, %t, %pi, "Text"); [a, b, c] = L(:) // RHS structure s(2,3).r = %pi; s(2,1).r = %i; s(2,2) = %e; s(2,:).r s.r([2 4 6]) [a, b, c] = s.r([2 4 6]) // Forbidden / Rejected LHS expressions (=> error) [m, n, m+n] = myfun(a,b) // Symbolic expressions like "m+n" are forbidden [p, 4.5, q] = myfun(a,b) // Literal LHS values or expressions like "4.5" are forbidden [r, s+3 ] = myfun(a,b) // Expressions mixing literals and symbols like "s+3" can't be LHS recipients
--> [a, b, c] = (%pi, %t, "test") c = test b = T a = 3.1415927 --> [a, b] = (%e, %f, "Hello") b = F a = 2.7182818 --> [a, b, a] = (%pi, %t, "test"); a a = 3.1415927