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Replace values in dataframe from another dataframe ? #pandas
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1. Substitute the NaN's in a dataframe with values from another dataframe | |
If you have two DataFrames of the same shape, then: | |
df[df.isnull()] = d2 | |
2.Replace values in a dataframe with values from another dataframe by conditions | |
DataFrame.mask() | |
A = B.mask(condition, A) | |
When condition is true, the values from A will be used, otherwise B's values will be used. | |
3. | |
Is there a way to merge the values from one dataframe onto another without getting the _X, _Y columns? I'd like the values on one column to replace all zero values of another column. | |
df1: | |
Name Nonprofit Business Education | |
X 1 1 0 | |
Y 0 1 0 <- Y and Z have zero values for Nonprofit and Educ | |
Z 0 0 0 | |
Y 0 1 0 | |
df2: | |
Name Nonprofit Education | |
Y 1 1 <- this df has the correct values. | |
Z 1 1 | |
----------------------- | |
df.loc[df.Name.isin(df1.Name), ['Nonprofit', 'Education']] = df1[['Nonprofit', 'Education']] | |
df | |
Out[27]: | |
Name Nonprofit Business Education | |
0 X 1 1 0 | |
1 Y 1 1 1 | |
2 Z 1 0 1 | |
3 Y 1 1 1 | |
[4 rows x 4 columns] |
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