normality_test_fl()
The function normality_test_fl() performs the Normality Test.
Note
normality_test_fl()is a UDF (user-defined function). For more information, see usage.- This function contains inline Python and requires enabling the python() plugin on the cluster.
Syntax
T | invoke normality_test_fl()(data, test_statistic,p_value)
Arguments
- data: The name of the column containing the set of data to be used for the test.
- test_statistic: The name of the column to store test statistic value for the results.
- p_value: The name of the column to store p-value for the results.
Usage
normality_test_fl() is a user-defined tabular function, to be applied using the invoke operator. You can either embed its code in your query, or install it in your database. There are two usage options: ad hoc and persistent usage. See the below tabs for examples.
For ad hoc usage, embed its code using the let statement. No permission is required.
let normality_test_fl = (tbl:(*), data:string, test_statistic:string, p_value:string)
{
let kwargs = pack('data', data, 'test_statistic', test_statistic, 'p_value', p_value);
let code = ```if 1:
from scipy import stats
data = kargs["data"]
test_statistic = kargs["test_statistic"]
p_value = kargs["p_value"]
def func(row):
statistics = stats.normaltest(row[data])
return statistics[0], statistics[1]
result = df
result[[test_statistic, p_value]] = df.apply(func, axis=1, result_type = "expand")
```;
tbl
| evaluate python(typeof(*), code, kwargs)
}
;
datatable(id:string, sample1:dynamic) [
'Test #1', dynamic([23.64, 20.57, 20.42, 27.1, 22.12, 33.56, 23.64, 20.57]),
'Test #2', dynamic([20.85, 21.89, 23.41, 35.09, 30.02, 26.52, 20.85, 21.89]),
'Test #3', dynamic([20.13, 20.5, 21.7, 22.02, 32.2, 32.79, 33.9, 34.22, 20.13, 20.5])
]
| extend test_stat= 0.0, p_val = 0.0
| invoke normality_test_fl('sample1', 'test_stat', 'p_val')
id sample1 test_stat p_val
Test #1, [23.64, 20.57, 20.42, 27.1, 22.12, 33.56, 23.64, 20.57], 7.4881873153941036, 0.023657060728893706
Test #2, [20.85, 21.89, 23.41, 35.09, 30.02, 26.52, 20.85, 21.89], 3.29982750330276, 0.19206647332255408
Test #3, [20.13, 20.5, 21.7, 22.02, 32.2, 32.79, 33.9, 34.22, 20.13, 20.5], 6.9868433851364324, 0.030396685911910585