error_element

• type: setup command.
• function: assert a random error defintion for the accelerator.

&error_element
    STRING name = NULL;
    STRING element_type = NULL;
    STRING item = NULL;
    STRING type = "gaussian";
    double amplitude = 0.0;
    double cutoff = 3.0;
    long bind = 1;
    long bind_number = 0;
    long post_correction = 0;
    long fractional = 0;
    long additive = 1;
    STRING after = NULL;
    STRING before = NULL;
&end

• name -- The possibly wildcarded name of the elements for which errors are being specified.
• element_type -- An optional, possibly wildcarded string giving the type of elements to which the errors should be applied. E.g., element_type=*MON* would match all beam position monitors. If this item is given, then name may be left blank.
• item -- The parameter of the elements to which the error pertains.
• type -- The type of random distribution to use. May be one of ``uniform'', ``gaussian'', or ``plus_or_minus''. A ``plus_or_minus'' error is equal in magnitude to the amplitude given, with the sign randomly chosen.
• amplitude -- The amplitude of the errors.
• cutoff -- The cutoff for the random distribution.
• bind, bind_number -- If bind_number is positive, then a positive value of bind indicates that bind_number successive elements having the same name will have the same error value. If bind is negative, then the sign of the error is alternated between successive elements.
• post_correction -- A flag indicating whether the errors should be added after orbit, tune, and chromaticity correction.
• fractional -- A flag indicating whether the errors are fractional, in which case the amplitude refers to the amplitude of the fractional error.
• additive -- A flag indicating that the errors should be added to the prior value of the parameter. If zero, then the errors replace the prior value of the parameter.
• after -- The name of an element. If given, the error is applied only to elements that follow the named element in the beamline.
• before -- The name of an element. If given, the error is applied only to elements that precede the named element in the beamline.