Package maths_fns :: Module consistency_tests :: Class Consistency
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Class Consistency

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Instance Methods [hide private]
 
__init__(self, frq=None, gx=None, gh=None, mu0=None, h_bar=None)
Consistency tests for data acquired at different magnetic fields.
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calc_sigma_noe(self, noe, r1)
Function for calculating the sigma NOE value.
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func(self, orientation=None, tc=None, r=None, csa=None, r1=None, r2=None, noe=None)
Function for calculating the three consistency testing values.
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Method Details [hide private]

__init__(self, frq=None, gx=None, gh=None, mu0=None, h_bar=None)
(Constructor)

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Consistency tests for data acquired at different magnetic fields.

These three tests are used to assess the consistency of datasets aquired at different magnetic fields. Inconsistency can affect extracted information from experimental data and can be caused by variations in temperature, concentration, pH, water suppression, etc. The approach is described in Morin & Gagne (2009) JBNMR, 45: 361-372.

This code calculates three functions for each residue. When comparing datasets from different magnetic fields, the value should be the same for each function as these are field independent. The J(0) function is the spectral density at the zero frequency and is obtained using a reduced spectral density approach (Farrow et al. (1995) JBNMR, 6: 153-162). The F_eta and F_R2 functions are the consistency functions proposed by Fushman et al. (1998) JACS, 120: 10947-10952.

To assess the consistency of its datasets, one should first calculate one of those values (J(0), F_eta and F_R2, preferentially J(0) as discussed in Morin & Gagne (2009) JBNMR, 45: 361-372) for each field. Then, the user should compare values obtained for different magnetic fields. Comparisons should proceed using correlation plots and histograms, and the user could also calculate correlation, skewness and kurtosis coefficients.

For examples, see Morin & Gagne (2009) JBNMR, 45: 361-372.

func(self, orientation=None, tc=None, r=None, csa=None, r1=None, r2=None, noe=None)

source code 

Function for calculating the three consistency testing values.

Three values are returned, J(0), F_eta and F_R2.