null.data {PivotalR} | R Documentation

## A Data Set with lots of `NA` values

### Description

An example `data.frame` which is used by examples in this user manual

### Usage

    data(null.data)

### Format

This data has 104 columns and 2000 rows.

### Details

This data set has lots of `NA` values in it. By using `as.db.data.frame`, one can put the data set into the connected database. All the `NA` values will be converted into `NULL` values.

The MADlib wrapper functions like `madlib.lm` and `link{madlib.glm}` will throw an error if there are `NULL` values in the data. So one needs to clean up the data before using the regression functions supplied by MADlib.

### Note

Lazy data loading is enabled in this package. So the user does not need to explicitly run `data(null.data)` to load the data. It will be loaded whenever it is used.

### Examples

    ## Not run:

    ## set up the database connection
    ## Assume that .port is port number and .dbname is the database name
    cid <- db.connect(port = .port, dbname = .dbname, verbose = FALSE)

    ## create a table from the example data.frame "abalone"
    delete("null_data", conn.id = cid)
    x <- as.db.data.frame(null.data, "null_data", conn.id = cid, verbose = FALSE)

    ## ERROR, because of NULL values
    fit <- madlib.lm(sf_mrtg_pct_assets ~ ris_asset + lncrcd + lnauto +
                     lnconoth + lnconrp + intmsrfv + lnrenr1a + lnrenr2a +
                     lnrenr3a, data = x)

    ## select columns
    y <- x[,c("sf_mrtg_pct_assets","ris_asset", "lncrcd","lnauto",
              "lnconoth","lnconrp","intmsrfv","lnrenr1a","lnrenr2a",
              "lnrenr3a")]

    dim(y)

    ## remove NULL values
    for (i in 1:10) y <- y[!is.na(y[i]),]

    dim(y)

    fit <- madlib.lm(sf_mrtg_pct_assets ~ ., data = y)

    fit

    db.disconnect(cid, verbose = FALSE)

    ## End(Not run)

[Package PivotalR version 0.1.18.3.1 Index]