# Compute a Copula on a Grid

### Description

Compute a grid of copula values. This function has the primary intention of supporting 3-D renderings or 2-D images of the *copulatic surface*. Users should be aware of the convention of the placement of the plotting origin and the various plotting mechanisms available to them in **R**. By convention copulatic surfaces start in lower left corner for *u = v = 0* but matrix conventions (or at least how some functions plot matrices) start with the origin in the upper left.

### Usage

1 |

### Arguments

`cop` |
A copula function; |

`para` |
Vector of parameters or other data structure, if needed, to pass to the copula; |

`delta` |
The |

`transpose` |
A logical to transpose the returned grid. This is needed if functions such as |

`...` |
Additional arguments to pass. |

### Value

The values for *\mathbf{C}(u,v)* are returned as a grid as an **R** `matrix`

.

### Author(s)

W.H. Asquith

### See Also

`EMPIRcopdf`

### Examples

1 2 3 4 5 6 7 8 9 10 11 12 13 | ```
## Not run:
the.grid <- gridCOP(cop=PSP)
the.grid[1,1] <- 0 # replace the NaN
image(the.grid) # ramps to the upper right
## End(Not run)
## Not run:
# See this composite copula also used in densityCOPplot() documentation.
para <- list(alpha=0.15, beta=0.90, kappa=0.06, gamma=0.96,
cop1=GHcop, cop2=PLACKETTcop, para1=5.5, para2=0.07)
GR <- gridCOP(cop=composite2COP, para=para, delta=0.005)
image(GR, col=terrain.colors(20)) # asymmetric, high curvature in top half
## End(Not run)
``` |