Consider the following query:
SELECT *
FROM
table_1
CROSS JOIN
table_2
WHERE
table_1.f1 >= table_2.f1001
AND (
table_1.f1 < table_2.f1002
OR table_2.f1002 IS NULL
)
Is it possible to implement this using Pandas, for example with pd.merge(how='cross')? Suppose we have two dataframes table_1 and table_1, and we need to do a cross join according to the conditions below:
table_1.f1 >= table_2.f1001 AND (table_1.f1 < table_2.f1002 OR table_2.f1002 IS NULL)
Answers:
Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may not help you solve the issue immediately. So please treat them as advisements. If you found the post helpful (or not), leave a comment & I’ll get back to you as soon as possible.
Method 1
You can do like
out = pd.merge(table_1, table_2,how='cross') out = out[out['f1'].ge(out['f1001']) & (out['f1'].lt(out['f1001']) | table_2['f1002'].isna())]
Method 2
Use merge and query:
out = pd.merge(table_1, table_2, how='cross')
.query("(f1 >= f1001) & ((f1 < f1002) | f1002.isna())")
Method 3
df.merge(df, on='cid', suffixes=('1','2')).query('qid1 < qid2')
something like that , use query after merge
All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0