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Create new LazyFrame

Source code

Description

This is simply a convenience function to create LazyFrames in a quick way. It is a wrapper around pl$DataFrame()$lazy(). Note that this should only be used for making examples and quick demonstrations.

Usage

pl$LazyFrame(...)

Arguments

… Anything that is accepted by pl$DataFrame()

Value

LazyFrame

Examples

library(polars)

pl$LazyFrame(
  a = list(c(1, 2, 3, 4, 5)),
  b = 1:5,
  c = letters[1:5],
  d = list(1:1, 1:2, 1:3, 1:4, 1:5)
) # directly from vectors

#> polars LazyFrame
#>  $describe_optimized_plan() : Show the optimized query plan.
#> 
#> Naive plan:
#> DF ["a", "b", "c", "d"]; PROJECT */4 COLUMNS; SELECTION: "None"

# from a list of vectors or data.frame
pl$LazyFrame(list(
  a = c(1, 2, 3, 4, 5),
  b = 1:5,
  c = letters[1:5],
  d = list(1L, 1:2, 1:3, 1:4, 1:5)
))

#> polars LazyFrame
#>  $describe_optimized_plan() : Show the optimized query plan.
#> 
#> Naive plan:
#> DF ["a", "b", "c", "d"]; PROJECT */4 COLUMNS; SELECTION: "None"

# custom schema
pl$LazyFrame(
  iris,
  schema = list(Sepal.Length = pl$Float32, Species = pl$String)
)$collect()

#> shape: (150, 5)
#> ┌──────────────┬─────────────┬──────────────┬─────────────┬───────────┐
#> │ Sepal.Length ┆ Sepal.Width ┆ Petal.Length ┆ Petal.Width ┆ Species   │
#> │ ---          ┆ ---         ┆ ---          ┆ ---         ┆ ---       │
#> │ f32          ┆ f64         ┆ f64          ┆ f64         ┆ str       │
#> ╞══════════════╪═════════════╪══════════════╪═════════════╪═══════════╡
#> │ 5.1          ┆ 3.5         ┆ 1.4          ┆ 0.2         ┆ setosa    │
#> │ 4.9          ┆ 3.0         ┆ 1.4          ┆ 0.2         ┆ setosa    │
#> │ 4.7          ┆ 3.2         ┆ 1.3          ┆ 0.2         ┆ setosa    │
#> │ 4.6          ┆ 3.1         ┆ 1.5          ┆ 0.2         ┆ setosa    │
#> │ 5.0          ┆ 3.6         ┆ 1.4          ┆ 0.2         ┆ setosa    │
#> │ …            ┆ …           ┆ …            ┆ …           ┆ …         │
#> │ 6.7          ┆ 3.0         ┆ 5.2          ┆ 2.3         ┆ virginica │
#> │ 6.3          ┆ 2.5         ┆ 5.0          ┆ 1.9         ┆ virginica │
#> │ 6.5          ┆ 3.0         ┆ 5.2          ┆ 2.0         ┆ virginica │
#> │ 6.2          ┆ 3.4         ┆ 5.4          ┆ 2.3         ┆ virginica │
#> │ 5.9          ┆ 3.0         ┆ 5.1          ┆ 1.8         ┆ virginica │
#> └──────────────┴─────────────┴──────────────┴─────────────┴───────────┘