.. _variables-continuous_design-scales:

""""""
scales
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Characteristic values to scale continuous design variables


.. toctree::
   :hidden:
   :maxdepth: 1



**Specification**

- *Alias:* cdv_scales 

- *Arguments:* REALLIST

- *Default:* vector values = 1 . (no scaling)


**Description**


Each real value in ``scales`` is a nonzero characteristic value to be
used in scaling each continuous design variable. They only have effect
when the associated method specifies ``scaling``.

This keyword is required for
:dakkw:`variables-continuous_design-scale_types` of <tt>'value'</tt> and
optional for <tt>'auto'</tt> and <tt>'log'</tt>. When specified in
conjunction with log, scale values are applied prior to the logarithm,
to permit log scaling of strictly negative design variables.

If a single real value is specified it will apply to all continuous
design variables. Otherwise, a scale value must be specified for each
continuous design variable.

*Usage Tips:*

When ``scales`` are specified, but not
:dakkw:`variables-continuous_design-scale_types`, the scaling type is assumed
to be 'value' for all continuous design variables.

Use scale values of 1.0 to selectively avoid scaling a subset of
the variables.

Scaling for linear constraints is applied *after* any continuous
variable scaling.

See the scaling information under specific methods, e.g.,
``method-*-scaling`` for details on how to use this keyword.



**Examples**


Two continuous design variables, one scaled by the characteristic value 4.0, the other log-scaled without additional value scaling

.. code-block::

      continuous_design = 2
        initial_point    -1.2      1.0
        lower_bounds     -200      0.001
        upper_bounds      200      2.0
        descriptors       'x1'     "x2"
        scale_types = 'value' 'log'
        scales = 4.0 1.0




