equal (=) assignment , comparison, equal sign

## Description

Assignment:

  The equal sign `=` is used to denote the assignment of value(s) to variable(s). The syntax can be :

  - `a=expr` where `a` is a variable name and `expr` a scilab expression which evaluates to a single result;

  - `[a,b,...]=expr` where `a`,`b`,`...` are variable names and `expr` a scilab expression which results in as many results as given variable names.

Comparison:

  The equal sign `=` is also used in the comparison operators:

  - `a==b` denotes equality comparison between the values of the expressions `a` and `b`;

  - `a~=b` denotes inequality comparison between the values of the expressions `a` and `b`;

  - `a<=b` and `a>=b` denote ordering comparison between the values of the expressions `a` and `b`.

  See comparison for semantic details.

## Examples

    a = sin(3.2)
    M = [2.1,3.3,8.5;7.6,6.7,6.9;0,6.3,8.8];
    [u,s] = schur(M)
    2*2 == 4
    [1:10] == 4
    "foo" == "bar"
    sparse([1,2;4,5;3,10],[1,2,3]) == sparse([1,2;4,5;3,10],[1,2,3])
    1~=2

## See also

- less
- greater
- boolean
- isequal
- comparison

## History

6.0 `~` (not) priority is now higher than the comparisons one (`== ~= <= >=`). For instance, `~%t==1` is parsed as `(~%t)==1` instead of `~(%t==1)` and now yields `%F` instead of `%T`.