Read CSV Using Polars in Python

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!pip3 install --user polars

Collecting polars
  Downloading polars-0.15.10-cp37-abi3-manylinux_2_17_x86_64.manylinux2014_x86_64.whl (14.6 MB)
     ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 14.6/14.6 MB 38.2 MB/s eta 0:00:0000:0100:01
Installing collected packages: polars
Successfully installed polars-0.15.10

import polars as pl

df = pl.read_csv(
    "rank53_j0_j0.csv",
    has_header=False,
    dtypes={
        "column_1": pl.UInt8,
        "column_2": pl.UInt8,
        "column_3": pl.UInt8,
        "column_4": pl.UInt16,
        "column_5": pl.Utf8,
    },
    null_values=[],
)
df.columns = ["i0", "i1", "i2", "i", "ranks"]
df

df["ranks"].is_null().sum()

1

(df["ranks"] == "NA").sum()

1

(df["ranks"] == "").sum()

0