alter_elements

• type: action command.
• function: modify the value of a parameter for one or more elements

&alter_elements
        STRING name = NULL;
        STRING item = NULL;
        STRING type = NULL;
        STRING exclude = NULL;
        double value = 0;
        STRING string_value = NULL;
        long differential = 0;
        long multiplicative = 0;
        long verbose = 0;
        long allow_missing_elements = 0;
        long allow_missing_parameters = 0;
        long start_occurence = 0;
        long end_occurence = 0;
        double s_start = -1;
        double s_end = -1;
        STRING before = NULL;
        STRING after = NULL;
&end

• name -- A possibly-wildcard-containing string giving the names of the elements to alter. If not specified, then one must specify type.
• item -- The name of the parameter to alter.
• type -- A possibly-wildcard-containing string giving the names of element types to alter. May be specified with name or by itself.
• exclude -- A possibly-wildcard-containing string giving the names of elements to excluded from alteration.
• value, string_value -- The new value for the parameter. Use string_value only if the parameter takes a character string as its value.
• differential -- If nonzero, the new value is the predefined value of the parameter plus the quantity given with value.
• multiplicative -- If nonozero, the new given value is the predefined value of the parameter times the quantity given with value.
• verbose -- If nonzero, information is printed to the standard output describing what elements are changed.
• allow_missing_elements -- If nonzero, then it is not an error if an element matching name does not exist. Normally, such an occurence is an error and terminates the program.
• allow_missing_parameters -- If nonzero, then it is not an error if an element does not have the parameter named with item. Normally, such an occurence is an error and terminates the program.
• start_occurence, end_occurence -- If nonzero, these give the starting and ending occurence numbers of elements that will be altered. N.B.: if wildcards are used, occurence number counting is for each set of identically-named elements separately, rather than for the sequence of matched elements.
• s_start, s_end -- If non-negative, these give the gaving and ending position limits for the end-of-element locations of elements to be altered.
• after -- The name of an element. If given, the alteration is applied only to elements that follow the named element in the beamline.
• before -- The name of an element. If given, the alteration is applied only to elements that precede the named element in the beamline.