================
Placing Symbols
================

Symbols are the circuit elements you place on the canvas.  Each one is
*self-describing*: it carries its own SLiCAP metadata (device prefix, node
names and order, model name, parameter names, a description and a documentation
link), so the netlister and the Properties dialog need nothing else.

Opening the place dialog
========================

Choose :menuselection:`Place --> Symbol…` (shortcut :kbd:`S`).

.. figure:: /GUI/img/place_symbol_dialog.png
   :alt: The Place Symbol dialog
   :width: 70%

   The Place Symbol dialog: pick a symbol from the list; its description is
   shown below the preview.

#. Select a symbol from the list — a preview and its description appear.
#. Click **OK** (or double-click the symbol).
#. Move the mouse onto the canvas and **click** to drop the symbol.
#. Keep clicking to place more copies of the same symbol; press :kbd:`Esc`
   to stop.

Basic SLiCAP symbols
====================

.. list-table::
   :header-rows: 1
   :widths: 22 12 66

   * - Symbol
     - Prefix
     - Description
   * - Resistor
     - ``R``
     - Resistor (nonzero resistance); variant ``R0`` allows zero resistance.
   * - Capacitor
     - ``C``
     - Capacitor.
   * - Inductor
     - ``L``
     - Inductor.
   * - Voltage source
     - ``V``
     - Independent voltage source.
   * - Current source
     - ``I``
     - Independent current source.
   * - VCVS / VCCS
     - ``VCVS`` / ``VCVS``
     - Voltage-controlled voltage / current source.
   * - CCVS / CCCS
     - ``CCVS`` / ``CCCS``
     - Current-controlled voltage / current source.
   * - Nullor
     - ``N``
     - The SLiCAP nullor (ideal amplifier element).
   * - Ideal transformer
     - ``T``
     - Ideal transformer.
   * - Gyrator
     - ``W``
     - Gyrator.
   * - Coupling factor
     - ``K``
     - Mutual-inductance coupling factor.
   * - Ground
     - ``GND``
     - Reference node (net ``0``).
   * - Port
     - ``PORT``
     - Named hierarchical / global connection.
     
Extended SLiCAP Symbols
=======================

The figure below shows the "Place" drop-down menu with all SLiCAP symbols.

.. Figure:: SLiCAP_symbols.png
    :width: 50%

NGspice Symbols
===============

The figure below shows the "Place" drop-down menu with all NGspice symbols.

.. Figure:: NGspice_symbols.png
    :width: 35%

Orienting a symbol
==================

Open a placed component's **Properties** dialog (double-click it) to set its
rotation (0/90/180/270°) and horizontal or vertical mirroring.  See
:doc:`/GUI/schematics/component_properties`.

Parameter defaults
==================

When a symbol is placed, its ``value`` parameter and any
reference designator fields are pre-filled with ``?`` as a reminder that they
must be set before the netlist is valid.  All other parameters (initial
conditions, statistical attributes, etc.) start empty and are omitted from the
netlist until you fill them in.

Double-click the component to open the **Properties** dialog and replace the
``?`` placeholders with real values.
