Using Pandas str.contains to compare row-by-row

Question

I have set up the following very simple database to illustrate what I'm trying to do:

teams = pd.DataFrame({"spreads":['New England Patriots -7.0','Atlanta Falcons 2.5','New Orleans Saints -4.5']})
teams['home'] = ['New England Patriots','Carolina Panthers','New Orleans Saints']
teams['away'] = ['Miami Dolphins','Atlanta Falcons','Tampa Bay Buccaneers']

I'm essentially trying to extract the spread value. At first I was trying to use str.contains to first extract the team name thus separating out the numeric value but it seems that I can't use that as a comparison tool for a row-by-row analysis. If anyone has any tips for how to extract the numeric value (I don't think I can use a regex because there are cases where no '-' sign appears) or at the very least tell me what methodology to use to determine if the team listed for each row is the home or away team I would greatly appreciate it.

If all the spreads have numbers at the end then you can use - teams.spreads.str.split().str[-1] — TrigonaMinima
– TrigonaMinima, Commented Aug 25, 2016 at 20:43

piRSquared · Accepted Answer · 2016-08-25 20:46:19Z

2

Use .str.extract

teams.spreads.str.extract(r'(-?\d+\.?\d*)', expand=False)

0    -7.0
1     2.5
2    -4.5
Name: spreads, dtype: object

Fancier

teams.spreads.str.extract(r'(?P<spread_val>-?\d+\.?\d*)', expand=True)

answered Aug 25, 2016 at 20:46

piRSquared

296k68 gold badges509 silver badges654 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Merlin · Accepted Answer · 2016-08-26 01:00:46Z

1

Try this Splitting Strings:

teams['spreads_val'] = teams['spreads'].str.rsplit(" ").str.get(-1)

0    -7.0
1     2.5
2    -4.5
Name: spreads_vals, dtype: object

answered Aug 26, 2016 at 1:00

Merlin

25.9k44 gold badges141 silver badges213 bronze badges

Collectives™ on Stack Overflow

Using Pandas str.contains to compare row-by-row

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related