# for

keyword entering a non-conditional loop

### Description

Used to define loops. Its syntax is:
`for variable=expression ,instruction, .. ,instruction,end`

`for variable=expression do instruction, ,instruction,end`

If `expression`

is a matrix or a row vector, `variable`

takes as values the values of each column of the matrix.

A particular case uses the colon operator to create regularly
spaced row vectors, and is similar to traditional for loop forms:
`for variable=n1:step:n2, ...,end`

If `expression`

is a list `variable`

takes as values the
successive entries of the list.

According to the Code Conventions for the Scilab Programming Language it is recommended:

Start each statement on a new line.

Write no more than one simple statement per line.

Break compound statements over multiple lines.

For example, use:

for i = 1:5 disp(i); end

for i = 1:5, disp(i); end

The number of characters used to define the body of any loop or conditional instruction
(if while for or select/case) must be limited to 16 kB. |

### Examples

Common loops:

n=5; for i = 1:n for j = 1:n a(i,j) = 1/(i+j-1); end; end for j = 2:n-1 a(j,j) = j; end; a

"Decreasing" loop:

for j = 4:-1:1 j end

Loop implicitly on the columns of a row vector or of a matrix:

M = [1 2 ; 3 4 ; 5 6]' for c = M, c, end

-> M = [1 2 ; 3 4 ; 5 6]' M = 1. 3. 5. 2. 4. 6. --> for c = M, c, end c = 1. 2. c = 3. 4. c = 5. 6.

for v = a, write(%io(2),v), end for j = 1:n, v = a(:,j), write(%io(2),v), end

Loop on entries of a list:

for l = list([1 2;3 4], (1+%z)^3, 'example', [%F %T]); l, end

--> for l = list([1 2;3 4], (1+%z)^3, 'example', [%F %T]); l, end l = 1. 2. 3. 4. l = 2 3 1 +3z +3z +z l = example l = F T

### See also

### History

Version | Description |

6.0.0 | The for `expression` can now be a vector of graphic handles.
`for` is now protected:
Assignments like `for=1` are no longer possible. |

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