Data transformations

There might come a time where you will need to add new columns to your dataset. You can customize these assignments based on your specific needs and conditions. This allows you to add new columns for various purposes such as filtering or to make other data-wrangling tasks easier.

These examples are taken from openvolley snippits.

The setter of a given attack

Aim: Identify the player who made the set associated with each attack (noting that some files might not have the setting action coded for all attacks, or even coded at all).

Python - adding set player name

Code

from datavolley import read_dv
import pandas as pd
from IPython.display import Markdown
import numpy as np
dv_instance = read_dv.DataVolley(None) # Replace `None` with path of your dvw file 
df = dv_instance.get_plays()
df['set_player_name'] = np.where((df['skill'] == 'Attack') & (df['skill'].shift(1) == 'Set') & (df['team'] == df['team'].shift(1)), df['player_name'].shift(1), np.nan)
filtered_df = df[df['skill'] == 'Attack'][['team', 'player_name', 'skill', 'evaluation_code', 'set_player_name']].head(5)

Markdown(filtered_df.to_markdown(index = False))

team	player_name	skill	evaluation_code	set_player_name
University of Dayton	Jamie Peterson	Attack	-	Brooke Westbeld
University of Louisville	Claire Chaussee	Attack	#	Lexi Hamilton
University of Dayton	Olivia Dubay	Attack	=	Brooke Westbeld
University of Dayton	Jamie Peterson	Attack	#	Brooke Westbeld
University of Louisville	Claire Chaussee	Attack	+	Shannon Shields

R - adding set player name

Code

library(datavolley)
library(dplyr)
x <- dv_read("datavolley//example_data.dvw") # Example data from python
px <- x$plays
px <- px %>% mutate(set_player_name = case_when(skill == "Attack" & lag(skill) == "Set" & team == lag(team) ~ lag(player_name)))
filtered_data <- px %>% select(team, player_name, skill, evaluation_code, set_player_name) %>% filter(skill == 'Attack') %>% head(5)
knitr::kable(filtered_data)

team	player_name	skill	evaluation_code	set_player_name
University of Dayton	Jamie Peterson	Attack	-	Brooke Westbeld
University of Louisville	Claire Chaussee	Attack	#	Lexi Hamilton
University of Dayton	Olivia Dubay	Attack	=	Brooke Westbeld
University of Dayton	Jamie Peterson	Attack	#	Brooke Westbeld
University of Louisville	Claire Chaussee	Attack	+	Shannon Shields

If you needed to add set code you can use the same code and replace player_name with set_code