If parameters specifications (pstr1 and pstr2) are given, there is no variable or vector setting. Instead, the indicated device parameters are altered directly, very similar to the alter command.
The syntax for the pstr strings is very similar to the device/parameter lists accepted by the show command.
device_list,param_list
The device_list is a list of one or more device names found in the circuit. The names are separated by white space, and the list is terminated with a comma. Following the comma is one or more parameter names. A parameter name is a device or model keyword, which should be applicable to all of the names listed in the device_list. The device keywords can be obtained from the show command.
The device_list can contain ``globbing'' (wild-card) characters with similar behavior to globbing (global substitution) in the WRspice shell. Briefly, `?' matches any character, '*' matches any set of characters or no characters, ``[abc]'' matches the characters `a', `b', and `c', and ``a{bc,de}'' matches ``abc'' and ``ade''.
If the string contains white space, it must be quoted. Since the same range is applied to all the parameters, if would be unusual to list more than one parameter name. However, wildcarding or multiple names in the device list allows setting the values of arbitrarily many devices for each trial.
If the device_list contains only a single name, and the name is a voltage or current source, resistor, capacitor, or inductor, then the comma and parameter name can be omitted. It will be taken as the output of a source, or the resistance, capacitance, or inductance of the component.