##### Compute the Number of Non-missing Observations

Compute the number of non-missing observations. Provides a 'default' method to handle vectors, and a method for data frames.

- Keywords
- attribute

##### Usage

```
nobs(object, ...)
# S3 method for default
nobs(object, ...)
# S3 method for data.frame
nobs(object, ...)
# S3 method for lm
nobs(object, ...)
```

##### Arguments

- object
Target Object

- …
Optional parameters (currently ignored)

##### Details

Calculate the number of observations in `object`

.

For numeric vectors, this is simply the number of non-NA elements, as computed by

`sum(!is.na(object))`

.For dataframe objects, the result is a vector containing the number of non-NA elementes of each column.

The `nobs`

and `nobs.lm`

functions defined in gtools are
simply aliases for the functions in the base R `stats`

package,
provided for backwards compatibility.

##### Value

Either single numeric value (for vectors) or a vector of numeric values (for data.frames) giving the number of non-missing values.

##### Note

The base R package `stats`

now provides a S3 dispatch function for
`nobs`

, and methods for for objects of classes "lm", "glm",
"nls" and "logLik", as well as a default method.

Since they provided a subset of the the functionality, the base
method dispatch (`nobs`

) function and method for "lm" objects
(`nobs.lm`

) are, as of `gdata`

version 2.10.1, simply
aliases for the equivalent functions in the base R `stats`

package.

Since `gdata`

's default method (`nobs.default`

) processes
vectors and hands any other data/object types to
`stats:::nobs.default`

.

##### See Also

##### Examples

```
x <- c(1,2,3,5,NA,6,7,1,NA )
length(x)
nobs(x)
df <- data.frame(x=rnorm(100), y=rnorm(100))
df[1,1] <- NA
df[1,2] <- NA
df[2,1] <- NA
nobs(df)
fit <- lm(y ~ x, data=df)
nobs(fit)
```

*Documentation reproduced from package gdata, version 2.18.0, License: GPL-2*