TTEST_1SAMP
The TTEST_1SAMP node is based on a numpy or scipy function. The description of that function is as follows:
Calculate the T-test for the mean of ONE group of scores.
This is a test for the null hypothesis that the expected value (mean) of a sample of independent observations 'a' is equal to the given population mean, 'popmean'. Params: select_return : 'statistic', 'pvalue' Select the desired object to return.
See the respective function docs for descriptors. a : array_like Sample observation. popmean : float or array_like Expected value in null hypothesis.
If array_like, then it must have the same shape as 'a' excluding the axis dimension. axis : int or None Axis along which to compute test.
Default is 0.
If None, compute over the whole array 'a'. nan_policy : {'propagate', 'raise', 'omit'} Defines how to handle when input contains nan.
The following options are available (default is 'propagate'):
'propagate' : returns nan
'raise' : raises an error
'omit' : performs the calculations ignoring nan values alternative : {'two-sided', 'less', 'greater'} Defines the alternative hypothesis.
The following options are available (default is 'two-sided'):
'two-sided' : the mean of the underlying distribution of the sample
is different than the given population mean (`popmean`)
'less' : the mean of the underlying distribution of the sample is
less than the given population mean (`popmean`)
'greater' : the mean of the underlying distribution of the sample is
greater than the given population mean (`popmean`) .. versionadded : : 1.6.0 Returns: out : DataContainer type 'ordered pair', 'scalar', or 'matrix'
Python Code
from flojoy import OrderedPair, flojoy, Matrix, Scalar
import numpy as np
from typing import Literal
import scipy.stats
@flojoy
def TTEST_1SAMP(
default: OrderedPair | Matrix,
popmean: float = 0.1,
axis: int = 0,
nan_policy: str = "propagate",
alternative: str = "two-sided",
select_return: Literal["statistic", "pvalue"] = "statistic",
) -> OrderedPair | Matrix | Scalar:
"""The TTEST_1SAMP node is based on a numpy or scipy function.
The description of that function is as follows:
Calculate the T-test for the mean of ONE group of scores.
This is a test for the null hypothesis that the expected value (mean) of a sample of independent observations 'a' is equal to the given population mean, 'popmean'.
Parameters
----------
select_return : 'statistic', 'pvalue'
Select the desired object to return.
See the respective function docs for descriptors.
a : array_like
Sample observation.
popmean : float or array_like
Expected value in null hypothesis.
If array_like, then it must have the same shape as 'a' excluding the axis dimension.
axis : int or None, optional
Axis along which to compute test.
Default is 0.
If None, compute over the whole array 'a'.
nan_policy : {'propagate', 'raise', 'omit'}, optional
Defines how to handle when input contains nan.
The following options are available (default is 'propagate'):
'propagate' : returns nan
'raise' : raises an error
'omit' : performs the calculations ignoring nan values
alternative : {'two-sided', 'less', 'greater'}, optional
Defines the alternative hypothesis.
The following options are available (default is 'two-sided'):
'two-sided' : the mean of the underlying distribution of the sample
is different than the given population mean (`popmean`)
'less' : the mean of the underlying distribution of the sample is
less than the given population mean (`popmean`)
'greater' : the mean of the underlying distribution of the sample is
greater than the given population mean (`popmean`)
.. versionadded:: 1.6.0
Returns
-------
DataContainer
type 'ordered pair', 'scalar', or 'matrix'
"""
result = scipy.stats.ttest_1samp(
a=default.y,
popmean=popmean,
axis=axis,
nan_policy=nan_policy,
alternative=alternative,
)
return_list = ["statistic", "pvalue"]
if isinstance(result, tuple):
res_dict = {}
num = min(len(result), len(return_list))
for i in range(num):
res_dict[return_list[i]] = result[i]
result = res_dict[select_return]
else:
result = result._asdict()
result = result[select_return]
if isinstance(result, np.ndarray):
result = OrderedPair(x=default.x, y=result)
else:
assert isinstance(
result, np.number | float | int
), f"Expected np.number, float or int for result, got {type(result)}"
result = Scalar(c=float(result))
return result