pandas select where condition code example

Example 1: or condition in pandas

df1 = df[(df.a != -1) & (df.b != -1)]

Example 2: or condition in pandas

df2 = df[(df.a != -1) | (df.b != -1)]

Example 3: slice dataframe pandas based on condition

# To slice pandas dataframe by condition

frioMurteira = data.loc[(data["POM"] == "Murteira") & (data["TMP"] > 7.2), ["DTM","TMP"]]

Example 4: python pandas dataframe conditional subset

In [722]: df[(df['C']==1) | df['B']]
Out[722]:
   A      B  C
0  1   True  1
2  2  False  1
3  2   True  2
4  3   True  1

In [723]: df.query('C==1 or B==True')
Out[723]:
   A      B  C
0  1   True  1
2  2  False  1
3  2   True  2
4  3   True  1

In [724]: df[df.eval('C==1 or B==True')]
Out[724]:
   A      B  C
0  1   True  1
2  2  False  1
3  2   True  2
4  3   True  1