Author: bugman
Date: Mon Jun 3 19:54:38 2013
New Revision: 19852
URL: http://svn.gna.org/viewcvs/relax?rev=19852&view=rev
Log:
Updated the relax_disp.select_model user function docstring for the R2eff
error analysis.
This properly describes how the R2eff/R1rho errors are calculated for the
fixed relaxation time
period experiments.
Modified:
branches/relax_disp/user_functions/relax_disp.py
Modified: branches/relax_disp/user_functions/relax_disp.py
URL:
http://svn.gna.org/viewcvs/relax/branches/relax_disp/user_functions/relax_disp.py?rev=19852&r1=19851&r2=19852&view=diff
==============================================================================
--- branches/relax_disp/user_functions/relax_disp.py (original)
+++ branches/relax_disp/user_functions/relax_disp.py Mon Jun 3 19:54:38 2013
@@ -489,9 +489,9 @@
uf.desc[-1].add_paragraph("This is the simplest of all models in that the
dispersion part is not modelled. It is used to determine the R2eff or R1rho
values and errors which are required as the base data for all other models.
It can be selected by setting the model to '%s'. Depending on the experiment
type, this model will be handled differently. The R2eff/R1rho values
determined can be later copied to the data pipes of the other dispersion
models using the appropriate value user function." % MODEL_R2EFF)
uf.desc[-1].add_paragraph("For the fixed relaxation time period CPMG-type
experiments, the R2eff values are determined by direct calculation using the
formula:")
uf.desc[-1].add_verbatim("""\
- -1 / I1(nu_CPMG) \
- R2,eff(nu_CPMG) = ------- * ln | ----------- | ,
- relax_T \ I0 /\
+ -1 / I1(nu_CPMG) \
+ R2eff(nu_CPMG) = ------- * ln | ----------- | ,
+ relax_T \ I0 /\
""")
uf.desc[-1].add_paragraph("where nu_CPMG is the CPMG frequency in Hz, equal
to:")
uf.desc[-1].add_verbatim("""\
@@ -499,13 +499,18 @@
nu_CPMG = ---------- ,
2 tau_CPMG\
""")
-uf.desc[-1].add_paragraph("relax_T is the fixed delay time, I0 is the
reference peak intensity when relax_T is zero, and I1 is the peak intensity
in a spectrum for a given nu_CPMG frequency. Errors are determined via
bootstrapping. The values and errors are determined with a single call of
the calc user function. The R1rho version of the equation is essentially the
same:")
+uf.desc[-1].add_paragraph("relax_T is the fixed delay time, I0 is the
reference peak intensity when relax_T is zero, and I1 is the peak intensity
in a spectrum for a given nu_CPMG frequency. The values and errors are
determined with a single call of the calc user function. The R1rho version
of the equation is essentially the same:")
uf.desc[-1].add_verbatim("""\
-1 / I1(nu1) \
R1rho(nu1) = ------- * ln | ------- | ,
relax_T \ I0 /\
""")
-uf.desc[-1].add_paragraph("where I1 is the peak intensity in a spectrum for
a given spin-lock field strength nu1.")
+uf.desc[-1].add_paragraph("where I1 is the peak intensity in a spectrum for
a given spin-lock field strength nu1. Errors are calculated using the
formula:")
+uf.desc[-1].add_verbatim("""\
+ / (sigma_I1 / I1(nu1))^2 + (sigma_I0 / I0)^2 \
+ sigma_R2 = sqrt | ------------------------------------------ | ,
+ \ relax_T /\
+""")
uf.desc[-1].add_paragraph("For the variable relaxation time period type
experiments, the R2eff/R1rho values are determined by fitting to the simple
two parameter exponential as in a R1 or R2 analyses. Both R2eff/R1rho and
the initial peak intensity I0 are optimised using the minimise user function
for each exponential curve separately. Monte Carlo simulations are used to
obtain the parameter errors.")
# The no exchange model.
uf.desc.append(Desc_container("The model for no chemical exchange
relaxation"))
r19852 - /branches/relax_disp/user_functions/relax_disp.py