Combining Columns from Two Datasets

The cbind function allows you to combine datasets by adding columns from one dataset into another. Note that when using cbind, the two datasets must have the same number of rows. In addition, if the datasets contain common column names, H2O will append the joined column with 0.

  • r
  • python
> library(h2o)
> h2o.init(nthreads=-1)

# Create two simple, two-column R data frames by inputting values, ensuring that both have a common column (in this case, "fruit").
> left <- data.frame(fruit = c('apple','orange','banana','lemon','strawberry','blueberry'), color = c('red','orange','yellow','yellow','red','blue'))
> right <- data.frame(fruit = c('apple','orange','banana','lemon','strawberry','watermelon'), citrus = c(FALSE, TRUE, FALSE, TRUE, FALSE, FALSE))

# Create the H2O data frames from the inputted data.
> l.hex <- as.h2o(left)
> print(l.hex)
        fruit  color
 1      apple    red
 2     orange orange
 3     banana yellow
 4      lemon yellow
 5 strawberry    red
 6  blueberry   blue

[6 rows x 2 columns]

> r.hex <- as.h2o(right)
> print(r.hex)
        fruit  color
 1      apple  FALSE
 2     orange   TRUE
 3     banana  FALSE
 4      lemon   TRUE
 5 strawberry  FALSE
 6 watermelon  FALSE

[6 rows x 2 columns]

# Combine the l.hex and r.hex datasets into a single dataset.
#The columns from r.hex will be appended to the right side of the final dataset. In addition, because both datasets include a "fruit" column, H2O will append the second "fruit" column name with "0".
#Note that this is different than ``merge``, which combines data from two commonly named columns in two datasets.

> columns.hex <- h2o.cbind(l.hex, r.hex)
> print(columns.hex)
       fruit  color     fruit0 citrus
1      apple    red      apple  FALSE
2     orange orange     orange   TRUE
3     banana yellow     banana  FALSE
4      lemon yellow      lemon   TRUE
5 strawberry    red strawberry  FALSE
6  blueberry   blue watermelon  FALSE

[6 rows x 4 columns]