redframes 1.4

General Purpose Data Manipulation Library

About

redframes (rectangular data frames) is a general purpose data manipulation library that prioritizes syntax, simplicity, and speed (to a solution). Importantly, the library is fully interoperable with pandas, compatible with scikit-learn, and works great with matplotlib.

Install & Import

pip install redframes

import redframes as rf

Quickstart

Copy-and-paste this to get started:

import redframes as rf

df = rf.DataFrame({
    'bear': ['Brown bear', 'Polar bear', 'Asian black bear', 'American black bear', 'Sun bear', 'Sloth bear', 'Spectacled bear', 'Giant panda'],
    'genus': ['Ursus', 'Ursus', 'Ursus', 'Ursus', 'Helarctos', 'Melursus', 'Tremarctos', 'Ailuropoda'],
    'weight (male, lbs)': ['300-860', '880-1320', '220-440', '125-500', '60-150', '175-310', '220-340', '190-275'],
    'weight (female, lbs)': ['205-455', '330-550', '110-275', '90-300', '45-90', '120-210', '140-180', '155-220']
})

# | bear                | genus      | weight (male, lbs)   | weight (female, lbs)   |
# |:--------------------|:-----------|:---------------------|:-----------------------|
# | Brown bear          | Ursus      | 300-860              | 205-455                |
# | Polar bear          | Ursus      | 880-1320             | 330-550                |
# | Asian black bear    | Ursus      | 220-440              | 110-275                |
# | American black bear | Ursus      | 125-500              | 90-300                 |
# | Sun bear            | Helarctos  | 60-150               | 45-90                  |
# | Sloth bear          | Melursus   | 175-310              | 120-210                |
# | Spectacled bear     | Tremarctos | 220-340              | 140-180                |
# | Giant panda         | Ailuropoda | 190-275              | 155-220                |

(
    df
        .rename({"weight (male, lbs)": "male", "weight (female, lbs)": "female"})
        .gather(["male", "female"], into=("sex", "weight"))
        .split("weight", into=["min", "max"], sep="-")
        .gather(["min", "max"], into=("stat", "weight"))
        .mutate({"weight": lambda row: float(row["weight"])})
        .group(["genus", "sex"])
        .rollup({"weight": ("weight", rf.stat.mean)})
        .spread("sex", using="weight")
        .mutate({"dimorphism": lambda row: round(row["male"] / row["female"], 2)})
        .drop(["male", "female"])
        .sort("dimorphism", descending=True)
)

# | genus      |   dimorphism |
# |:-----------|-------------:|
# | Ursus      |         2.01 |
# | Tremarctos |         1.75 |
# | Helarctos  |         1.56 |
# | Melursus   |         1.47 |
# | Ailuropoda |         1.24 |

For comparison, here's the equivalent pandas:

import pandas as pd

# df = pd.DataFrame({...})

df = df.rename(columns={"weight (male, lbs)": "male", "weight (female, lbs)": "female"})
df = pd.melt(df, id_vars=['bear', 'genus'], value_vars=['male', 'female'], var_name='sex', value_name='weight')
df[["min", "max"]] = df["weight"].str.split("-", expand=True)
df = df.drop("weight", axis=1)
df = pd.melt(df, id_vars=['bear', 'genus', 'sex'], value_vars=['min', 'max'], var_name='stat', value_name='weight')
df['weight'] = df["weight"].astype('float')
df = df.groupby(["genus", "sex"])["weight"].mean()
df = df.reset_index()
df = pd.pivot_table(df, index=['genus'], columns=['sex'], values='weight')
df = df.reset_index()
df = df.rename_axis(None, axis=1)
df["dimorphism"] = round(df["male"] / df["female"], 2)
df = df.drop(["female", "male"], axis=1)
df = df.sort_values("dimorphism", ascending=False)
df = df.reset_index(drop=True)

# 🤮

IO

Save, load, and convert rf.DataFrame objects:

# save .csv
rf.save(df, "bears.csv")

# load .csv
df = rf.load("bears.csv")

# convert redframes → pandas
pandas_df = rf.unwrap(df)

# convert pandas → redframes
df = rf.wrap(pandas_df)

Verbs

Verbs are pure and "chain-able" methods that manipulate rf.DataFrame objects. Here is the complete list (see docstrings for examples and more details):

Verb	Description
accumulate‡	Run a cumulative sum over a column
append	Append rows from another DataFrame
combine	Combine multiple columns into a single column (opposite of split)
cross	Cross join columns from another DataFrame
dedupe	Remove duplicate rows
denix	Remove rows with missing values
drop	Drop entire columns (opposite of select)
fill	Fill missing values "down", "up", or with a constant
filter	Keep rows matching specific conditions
gather‡	Gather columns into rows (opposite of spread)
group	Prepare groups for compatible verbs‡
join	Join columns from another DataFrame
mutate	Create a new, or overwrite an existing column
pack‡	Collate and concatenate row values for a target column (opposite of unpack)
rank‡	Rank order values in a column
rename	Rename column keys
replace	Replace matching values within columns
rollup‡	Apply summary functions and/or statistics to target columns
sample	Randomly sample any number of rows
select	Select specific columns (opposite of drop)
shuffle	Shuffle the order of all rows
sort	Sort rows by specific columns
split	Split a single column into multiple columns (opposite of combine)
spread	Spread rows into columns (opposite of gather)
take‡	Take any number of rows (from the top/bottom)
unpack	"Explode" concatenated row values into multiple rows (opposite of pack)

Properties

In addition to all of the verbs there are several properties attached to each DataFrame object:

df["genus"] 
# ['Ursus', 'Ursus', 'Ursus', 'Ursus', 'Helarctos', 'Melursus', 'Tremarctos', 'Ailuropoda']

df.columns 
# ['bear', 'genus', 'weight (male, lbs)', 'weight (female, lbs)']

df.dimensions
# {'rows': 8, 'columns': 4}

df.empty
# False

df.memory
# '2 KB'

df.types
# {'bear': object, 'genus': object, 'weight (male, lbs)': object, 'weight (female, lbs)': object}

matplotlib

rf.DataFrame objects integrate seamlessly with matplotlib:

import redframes as rf
import matplotlib.pyplot as plt

football = rf.DataFrame({
    'position': ['TE', 'K', 'RB', 'WR', 'QB'],
    'avp': [116.98, 131.15, 180, 222.22, 272.91]
})

df = (
    football
        .mutate({"color": lambda row: row["position"] in ["WR", "RB"]})
        .replace({"color": {False: "orange", True: "red"}})
)

plt.barh(df["position"], df["avp"], color=df["color"]);

scikit-learn

rf.DataFrame objects are fully compatible with sklearn functions, estimators, and transformers:

import redframes as rf
from sklearn.model_selection import train_test_split
from sklearn.linear_model import LinearRegression

df = rf.DataFrame({
    "touchdowns": [15, 19, 5, 7, 9, 10, 12, 22, 16, 10],
    "age": [21, 22, 21, 24, 26, 28, 30, 35, 28, 21],
    "mvp": [1, 1, 0, 0, 0, 0, 0, 1, 0, 0]
})

target = "touchdowns"
y = df[target]
X = df.drop(target)
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.3, random_state=1)

model = LinearRegression()
model.fit(X_train, y_train)
model.score(X_test, y_test)
# 0.5083194901655527

print(X_train.take(1))
# rf.DataFrame({'age': [21], 'mvp': [0]})

X_new = rf.DataFrame({'age': [22], 'mvp': [1]})
model.predict(X_new)
# array([19.])