Type and property representing negative rational numbers

Use only in the MuPAD Notebook Interface.

This functionality does not run in MATLAB.


testtype(obj, Type::NegRat)
assume(x, Type::NegRat)
is(ex, Type::NegRat)


Type::NegRat represents negative rational numbers. Type::NegRat is a property, too, which can be used in an assume call.

The call testtype(obj, Type::NegRat) checks, whether obj is a negative rational number and returns TRUE, if it holds, otherwise FALSE.

testtype only performs a syntactical test identifying MuPAD® objects of type DOM_INT and DOM_RAT and checks, if bool(obj < 0) holds.

The call assume(x, Type::NegRat) marks the identifier x as a negative rational number.

The call is(ex, Type::NegRat) derives, whether the expression ex is a negative rational number (or this property can be derived).

This type represents a property that can be used in assume and is.


Example 1

The following numbers are of type Type::NegRat:

testtype(-2, Type::NegRat),
testtype(-3/4, Type::NegRat),
testtype(-55/111, Type::NegRat),
testtype(-1, Type::NegRat),
testtype(-111/111111, Type::NegRat)

Example 2

Assume an identifier is negative rational:

assume(x, Type::NegRat):
is(x, Type::NegRat)

Also negative rational numbers are rational:

assume(x, Type::NegRat):
is(x, Type::Rational)

However, rational numbers can be negative rational or not:

assume(x, Type::Rational):
is(x, Type::NegRat)

delete x:



Any MuPAD object


An identifier or a mathematical expression containing identifiers


An arithmetical expression

Return Values

See testtype, assume and is

See Also

MuPAD Functions

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