# Core CIF Dictionary version 2.3

# _reflns_class_R_factor_

### Names

`'_reflns_class_R_factor_all'`
`'_reflns_class_R_factor_gt'`
**Category:** reflns_class

**Data type:** numb

**Must** appear in a looped list
containing `'_reflns_class_code'`

**Enumeration range:** 0.0 -> infinity

### Definition

For each reflection class, the residual factors for all
reflections, and for significantly intense reflections (see
_reflns_threshold_expression) and included in the refinement.
The reflections also satisfy the resolution limits established by
_reflns_class_d_res_high and _reflns_class_d_res_low.
This is the conventional R factor.
sum | F(obs) - F(calc) |
R = ------------------------
sum | F(obs) |
F(obs) = the observed structure-factor amplitudes
F(calc) = the calculated structure-factor amplitudes
and the sum is taken over the reflections of this class. See also
_reflns_class_wR_factor_all definitions.

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