## What are covariant and contravariant tensors?

In differential geometry, the components of a vector relative to a basis of the tangent bundle are covariant if they change with the same linear transformation as a change of basis. They are contravariant if they change by the inverse transformation.

## What are contravariant tensors?

A contravariant tensor is a tensor having specific transformation properties (cf., a covariant tensor). To examine the transformation properties of a contravariant tensor, first consider a tensor of rank 1 (a vector)

**Can we add covariant and contravariant tensor?**

Covariant and contravariant indices can be used simultaneously in a mixed tensor. Therefore, raising and lowering indices is trivial, hence covariant and contravariant tensors have the same coordinates, and can be identified.

**What is the difference between covariance and contravariance?**

Covariance permits a method to have a return type that is a subtype of the one defined in the delegate. Contravariance permits a method to have a parameter type that is a base type of the one defined in the delegate type.

### What is the meaning of contravariant?

Adjective. contravariant (not comparable) (category theory, of a functor) which reverses composition.

### What is meant by covariance and Contravariance?

Covariance and contravariance are terms that refer to the ability to use a more derived type (more specific) or a less derived type (less specific) than originally specified. Generic type parameters support covariance and contravariance to provide greater flexibility in assigning and using generic types.

**What is the difference between covariance and Contravariance?**

**Is metric tensor A covariant contravariant?**

Also, the contravariant (covariant) forms of the metric tensor are expressed as the dot product of a pair of contravariant (covariant) basis vectors. Two vectors may be multiplied in the manner of a dot product, which produces a scalar, or in the manner of a cross product that produces another vector.

#### What does contravariance mean?

contravariance (countable and uncountable, plural contravariances) (object-oriented programming) The reversal of the order of data types acted upon by an operator. quotations â–¼coordinate term â–¼ (category theory) A functor which reverses composition.

#### What is covariance in OOP?

Covariance means that a method can return a type that is derived from the delegate’s return type. Contra-variance means that a method can take a parameter that is a base of the delegate’s parameter type.

**What is meant by covariance and contravariance?**