4.7. DataFrame At

• Access a single value for a row/column pair by integer position

• Use iat if you only need to get or set a single value in a DataFrame or Series

• iat integer at (no fancy indexing)

Figure 4.1. Pandas Select Cell

import pandas as pd
import numpy as np
np.random.seed(0)

df = pd.DataFrame(
    columns = ['Morning', 'Noon', 'Evening', 'Midnight'],
    index = pd.date_range('1999-12-30', periods=7),
    data = np.random.randn(7, 4))

df
#              Morning      Noon   Evening  Midnight
# 1999-12-30  1.764052  0.400157  0.978738  2.240893
# 1999-12-31  1.867558 -0.977278  0.950088 -0.151357
# 2000-01-01 -0.103219  0.410599  0.144044  1.454274
# 2000-01-02  0.761038  0.121675  0.443863  0.333674
# 2000-01-03  1.494079 -0.205158  0.313068 -0.854096
# 2000-01-04 -2.552990  0.653619  0.864436 -0.742165
# 2000-01-05  2.269755 -1.454366  0.045759 -0.187184

4.7.1. Get value at specified row/column pair

• First argument is column

• Second argument is row

df.iat[0,0]
# 1.764052345967664

df.iat[1,0]
# 1.8675579901499675

df.iat[0,1]
# 0.4001572083672233

4.7.2. Get value from row

• loc returns Series

df.loc['2000-01-01'].iat[1]
# 0.41059850193837233

4.7.3. Set value at a position

df.iat[0,0] = 0.0
df
#              Morning      Noon   Evening  Midnight
# 1999-12-30  0.000000  0.400157  0.978738  2.240893
# 1999-12-31  1.867558 -0.977278  0.950088 -0.151357
# 2000-01-01 -0.103219  0.410599  0.144044  1.454274
# 2000-01-02  0.761038  0.121675  0.443863  0.333674
# 2000-01-03  1.494079 -0.205158  0.313068 -0.854096
# 2000-01-04 -2.552990  0.653619  0.864436 -0.742165
# 2000-01-05  2.269755 -1.454366  0.045759 -0.187184

4.7.4. Assignments

Todo

Create assignments