### Compile and Install Xnec2c from Source

Source: https://www.xnec2c.org/

Standard sequence of commands to clone, configure, and build the Xnec2c software from the GitHub repository.

```bash
git clone https://github.com/KJ7LNW/xnec2c.git
cd xnec2c
./autogen.sh
./configure
make && make install
make desktop-install # Optional: for icons and file association.
xnec2c
```

--------------------------------

### Parametric Yagi Model Example

Source: https://www.xnec2c.org/

This example demonstrates how symbols cascade through a model, where changing the FREQ symbol propagates to element lengths and positions.

```text
SY FREQ=146, C=299.792458, LAMBDA=C/FREQ
SY L_REF=0.492*LAMBDA, L_DRV=0.468*LAMBDA
SY X_DRV=0.193*LAMBDA, RADIUS=AWG_10
GW 1 25 0 L_REF/2 0 0 -L_REF/2 0 RADIUS
GW 2 25 X_DRV L_DRV/2 0 X_DRV -L_DRV/2 0 RADIUS
FR 0 21 0 0 FREQ-5 0.5
```

--------------------------------

### Install Build Dependencies on Debian/Ubuntu

Source: https://www.xnec2c.org/

Required development libraries and build tools for Debian or Ubuntu distributions.

```bash
apt-get install build-essential autoconf libtool gnome-devel libgsl-dev libgtk-3-dev gettext autopoint gnome-icon-theme desktop-file-utils libepoxy-dev libgl-dev
```

--------------------------------

### Install Xnec2c on Linux via Flathub

Source: https://www.xnec2c.org/

Use the flatpak command to install the Xnec2c binary package on Linux systems.

```bash
flatpak install flathub org.xnec2c.Xnec2c
```

--------------------------------

### Install Xnec2c on macOS via MacPorts

Source: https://www.xnec2c.org/

Use the MacPorts package manager to install Xnec2c on macOS.

```bash
sudo port install xnec2c
```

--------------------------------

### Install Build Dependencies on RHEL-based Systems

Source: https://www.xnec2c.org/

Required development libraries and build tools for Rocky, Alma, Oracle, RHEL, or CentOS distributions.

```bash
yum install gcc make automake autoconf gsl-devel gtk3-devel gettext-devel libtool libepoxy-devel mesa-libGL-devel
```

--------------------------------

### Monitor frequency loop timing with -vv

Source: https://www.xnec2c.org/

Example console output when running xnec2c with the -vv flag to observe frequency loop timing for 2m_yagi.nec.

```text
[info] 140.000000 MHz: 0.045850 seconds. (ATLAS, Threaded)
[info] 141.500000 MHz: 0.054378 seconds. (ATLAS, Threaded)
[info] 140.000000 MHz: 0.063772 seconds. (ATLAS, Threaded)
[info] 140.500000 MHz: 0.066472 seconds. (ATLAS, Threaded)
[info] 141.000000 MHz: 0.078861 seconds. (ATLAS, Threaded)
[info] 142.000000 MHz: 0.047910 seconds. (ATLAS, Threaded)
[info] 143.000000 MHz: 0.068066 seconds. (ATLAS, Threaded)
[info] 143.500000 MHz: 0.076449 seconds. (ATLAS, Threaded)
[info] 144.000000 MHz: 0.068083 seconds. (ATLAS, Threaded)
[info] 142.500000 MHz: 0.113185 seconds. (ATLAS, Threaded)
[info] 146.000000 MHz: 0.050178 seconds. (ATLAS, Threaded)
[info] 144.500000 MHz: 0.051486 seconds. (ATLAS, Threaded)
[info] 145.000000 MHz: 0.058897 seconds. (ATLAS, Threaded)
[info] 145.500000 MHz: 0.060019 seconds. (ATLAS, Threaded)
[info] 147.000000 MHz: 0.057313 seconds. (ATLAS, Threaded)
[info] 146.500000 MHz: 0.070968 seconds. (ATLAS, Threaded)
[info] 148.000000 MHz: 0.071760 seconds. (ATLAS, Threaded)
[info] 147.500000 MHz: 0.080575 seconds. (ATLAS, Threaded)
[info] 148.500000 MHz: 0.051870 seconds. (ATLAS, Threaded)
[info] 149.500000 MHz: 0.058890 seconds. (ATLAS, Threaded)
[info] 150.000000 MHz: 0.056449 seconds. (ATLAS, Threaded)
[info] 149.000000 MHz: 0.071011 seconds. (ATLAS, Threaded)
[notice] Frequency loop elapsed time: 0.467847 seconds. (ATLAS, Threaded)
```

--------------------------------

### SY Card Syntax Examples

Source: https://www.xnec2c.org/

SY cards define variables using direct values or expressions. Multiple definitions can be placed on a single line, with left-to-right evaluation allowing later symbols to reference earlier ones.

```text
SY name=value
SY name=expression
SY a=1, b=a*2, c=b+1
```

--------------------------------

### Launch Xnec2c with Multi-threading

Source: https://www.xnec2c.org/

Launch the application specifying the number of CPU jobs to use for simulation.

```bash
xnec2c -j8
```

--------------------------------

### Alternative Autoconf Command

Source: https://www.xnec2c.org/

Use this command if the standard ./autogen.sh script fails to provide sufficient diagnostic information.

```bash
autoreconf -v -i -W all
```

--------------------------------

### Symbol Overrides File Format

Source: https://www.xnec2c.org/

The .sy file stores symbol tuning state in a text format, allowing overrides to persist across application restarts.

```text
# Symbol overrides file
FREQ: min_value=100 max_value=200 override_value=146 override_active=1
LAMBDA: min_value=1.0 max_value=4.0 override_value=2.05 override_active=0
```

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