Package 'RcppNarrow'

First Steps Around 'narrow'

Description

Leaning on the 'narrow' package for C-level access to 'Arrow' without requiring the full weight of that package.

Package Content

Index of help topics:

describeArrowArray      Describe An Arrow Array
describeArrowSchema     Describe An Arrow Schema
extract_null_count      Count Null Elements in Arrow Object
narrow_array_info       Call array info
print_uint64            Print uint64_t vector
RcppNarrow-package      First Steps Around 'narrow'

Maintainer

Dirk Eddelbuettel <[email protected]>

Author(s)

Dirk Eddelbuettel

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Describe An Arrow Array

Description

Describe An Arrow Array

Usage

describeArrowArray(ptr)

Arguments

ptr	An external pointer object for an ArrowArray structure

Value

None. The function is invoked for the side effect of displaingy some array info.

---

Describe An Arrow Schema

Description

Describe An Arrow Schema

Usage

describeArrowSchema(ptr)

Arguments

ptr	An external pointer object for an ArrowSchema structure

Value

None. The function is invoked for the side effect of displaying the schema info.

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Count Null Elements in Arrow Object

Description

Count Null Elements in Arrow Object

Usage

extract_null_count(array_data_xptr)

Arguments

array_data_xptr

An external pointer to an Arrow object

Value

The number of null elements

Examples

if (requireNamespace("narrow", quietly=TRUE)) {
    extract_null_count(narrow::as_narrow_array(c(NA, NA, 1:5))$array_data)
}

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Call array info

Description

Call array info

Usage

narrow_array_info(adptr)

Arguments

adptr

An external pointer to array data object

Value

A list with array info

Examples

if (requireNamespace("narrow", quietly=TRUE)) {
    x <- narrow::as_narrow_array(c(NA, 2, NA, 4:7))
    narrow_array_info(x$array_data)
}

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Print uint64_t vector

Description

Print uint64_t vector

Usage

print_uint64(ptr)

Arguments

ptr	An external pointer object for an uint64_t vector

Value

None. The function is invoked for the side effect of display schema info.

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