crossprod {base} | R Documentation |

## Matrix Crossproduct

### Description

Given matrices `x`

and `y`

as arguments,
`crossprod`

returns their matrix cross-product.
This is formally equivalent to, but faster than, the
call `t(x) %*% y`

.

### Usage

crossprod(x, y = NULL)

### Arguments

`x, y` |
matrices: `y = NULL` is taken to be the
same matrix as `x` . Vectors are promoted to single-column
matrices. |

### References

Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988)
*The New S Language*.
Wadsworth & Brooks/Cole.

### See Also

`%*%`

and outer product `%o%`

.

### Examples

(z <- crossprod(1:4)) # = sum(1 + 2^2 + 3^2 + 4^2)
drop(z) # scalar

[Package

*base* version 2.2.1

Index]