<< diag Matrix generation eye >>
Scilab Help >> Elementary Functions > Matrix generation > empty

empty

([]) empty matrix

Description

[] denotes the empty matrix. It is uniquely defined and has 0 row and 0 column, i.e. size([]) =[0,0]. The following convenient conventions are made:

[] * A = A * [] = []

[] + A = A + [] = []

[ [], A] = [A, []] = A

Matrix functions return [] or an error message when there is no obvious answer. Empty linear systems (syslin lists) may have several rows or columns.

Examples

s=poly(0,'s');
A = [s, s+1];
A+[], A*[]
A=rand(2,2);
AA=A([],1), size(AA)
svd([])
w=ssrand(2,2,2);
wr=[]*w;
size(wr), w1=ss2tf(wr), size(w1)

See also

History

VersionDescription
6.0.0
  • A+[], []+A and A-[] now return [] instead of A. []-A now returns [] instead of -A.
  • A>[], A>=[], A<[], A<=[], []>A, []>=A, []<A, and []<=A now return [] instead of an error.

Report an issue
<< diag Matrix generation eye >>