Parameter#

class amplpy.Parameter(_impl)#

Represents an AMPL parameter. The values can be float or string (in case of symbolic parameters).

Data can be assigned to the set using the methods set() and set_values() or using set_data() and an object of class DataFrame.

__setitem__(index, value)#
is_symbolic()#

Returns True if the parameter is declared as symbolic (can store both numerical and string values).

has_default()#

Check if the parameter has a default initial value. In case of the following AMPL code:

param a;
param b default a;

the function will return true for parameter b.

Returns:

True if the parameter has a default initial value. Please note that if the parameter has a default expression which refers to another parameter which value is not defined, this will return True.

value()#

Get the value of this parameter. Valid only for non-indexed parameters.

set(*args)#

Set the value of a single instance of this parameter.

Args:

args: value if the parameter is scalar, index and value otherwise.

Raises:

RuntimeError: If the entity has been deleted in the underlying AMPL.

TypeError: If the parameter is not scalar and the index is not provided.

set_values(values)#

Assign the values (string or float) to the parameter instances with the specified indices, equivalent to the AMPL code:

let {i in indices} par[i] := values[i];
Args:

values: list, dictionary or DataFrame with the indices and the values to be set.

Raises:

TypeError: If called on a scalar parameter.

__annotations__ = {}#