comparison

comparison, relational operators

Calling Sequence

a==b
a~=b or a<>b
a<b
a<=b
a>b
a>=b

Arguments

:a any type of variable for a==b, a~=b a<>b equality comparisons

and restricted to real floating point and integer array for order related comparisons a<b, a<=b, a>b, a>=b.

: :b any type of variable for a==b, a~=b a<>b equality

comparisons and restricted to real floating point and integer arrays for order related comparisons a<b, a<=b, a>b, a>=b.

:

Description

Two classes of operators have to be distinguished:

The equality and inequality comparisons:  a==b, a~=b (or equivalently a<>b). These operators apply to any type of operands.

: :The order related comparisons: a<b, a<=b, a>b, a>=b. These

operators apply only to real floating point and integer arrays.

:

The semantics of the comparison operators also depend on the operands types:

:With array variables like floating point and integer arrays, logical arrays, string arrays, polynomial and rational arrays, handle arrays, lists... the following rules apply:

• If a and b evaluates as arrays with same types and identical dimensions, the comparison is performed element by element and the result is an array of booleans of the same size.
• If a and b evaluates as arrays with same types, but a or b is a scalar, then the scalar is compared with each element of the other array. The result is an array of booleans of the size of the non scalar operand.
• In the others cases the result is the boolean %f
• If the operand data types are different but “compatible” like floating points and integers, then a type conversion is performed before the comparison.

: :With other type of operands like function, libraries, the

result is %t if the objects are identical and %f in the other cases. Equality comparison between operands of incompatible data types returns %f.

:

Examples

//element wise comparisons
(1:5)==3
(1:5)<=4
(1:5)<=[1 4 2 3 0]
1<[]
`list`_(1,2,3)~=`list`_(1,3,3)

//object wise comparisons
(1:10)==[4,3]
'foo'==3
1==[]
`list`_(1,2,3)==1

`isequal`_(`list`_(1,2,3),1)
`isequal`_(1:10,1)

//comparison with type conversion
`int32`_(1)==1
`int32`_(1)<1.5
`int32`_(1:5)<`int8`_(3)
p=`poly`_(0,'s','c')
p==0
p/`poly`_(1,'s','c')==0

See Also

• less (<) less than comparison
• greater
• boolean Scilab Objects, boolean variables and operators & | ~
• isequal objects comparison