Oleksiy Kononenko

Results 26 issues of Oleksiy Kononenko

The code ```python from datatable import dt DT = dt.Frame(["a", None, "b"]) print(DT.to_csv(quoting="all")) ``` prints ```python '"C0"\n"a"\n\n"b"\n' ``` However, according to [documentation](https://datatable.readthedocs.io/en/latest/api/frame/to_csv.html#quoting), when `quoting="all"` all the fields should be quoted....

bug

```python >>> from datatable import dt >>> DT = dt.Frame({"\t" : [1]}) >>> DT.names ('.',) ```

Several tests are failing on Windows for the following profile: - python `3.8.10` (not all the `3.8` pythons are failing, for instance, `3.8.0` doesn't fail); - datatable debug build (release...

bug

Currently it is impossible to create a datatable frame from numpy arrays with unsigned integer types: ```python >>> import datatable as dt >>> import numpy as np >>> NP =...

improve

Right now datatable reducers are only parallelized in terms of the groups. When there is one group, even if it is huge, datatable does all the work in single thread....

improve
performance

```python from datatable import dt, f, sort DT = dt.Frame([[1], [1]]) DT[:, :, sort(f[:])] ``` produces ```python AssertionError: Assertion 'flags.size() == ncols' failed in src/core/expr/eval_context.cc, line 264 ```

bug

RIght now datatable frames cannot be created from `pd.array()` ```python >>> import datatable as dt >>> import pandas as pd >>> PD = pd.array([1, 2, None]) >>> DT = dt.Frame(PD)...

improve

`.replace()` [should operate](https://datatable.readthedocs.io/en/latest/api/frame/replace.html) on columns of types appropriate for the `replace_what` value. At the same time, we [declare](https://datatable.readthedocs.io/en/latest/api/type/void.html) that `void` columns can be used in place where any other type...

bug

There is an issue caused by PR https://github.com/h2oai/datatable/pull/3144. All the `.jay` files produced by datatable as of this PR are causing segfaults, when read by any of the older datatable...

segfault