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spectrochempy.set_nmr_context

set_nmr_context(larmor)

Set a NMR context relative to the given Larmor frequency.

Parameters

larmor (Quantity or float) – The Larmor frequency of the current nucleus. If it is not a quantity it is assumed to be given in MHz.

Examples

First we set the NMR context,

>>> from spectrochempy.core.units import ur, set_nmr_context
>>>
>>> set_nmr_context(104.3 * ur.MHz)

then, we can use the context as follow

>>> fhz = 10000 * ur.Hz
>>> with ur.context('nmr'):
...     fppm = fhz.to('ppm')
>>> print("{:~.3f}".format(fppm))
95.877 ppm

or in the opposite direction

>>> with ur.context('nmr'):
...     fhz = fppm.to('kHz')
>>> print("{:~.3f}".format(fhz))
10.000 kHz

Now we update the context :

>>> with ur.context('nmr', larmor=100. * ur.MHz):
...     fppm = fhz.to('ppm')
>>> print("{:~.3f}".format(fppm))
100.000 ppm

>>> set_nmr_context(75 * ur.MHz)
>>> fhz = 10000 * ur.Hz
>>> with ur.context('nmr'):
...     fppm = fhz.to('ppm')
>>> print("{:~.3f}".format(fppm))
133.333 ppm