How to change font scale from Terminal

This answer from StackOverflow (How to change font size by adb command) provides a solution. The command used to set the font size is:

adb shell settings put system font_scale {
float_representing_the_scale
}

or if you are using a terminal emulator in Android

settings put system font_scale {
float_representing_the_scale
}

Examples:

settings put system font_scale 0.5f

settings put system font_scale 1.2f

I tested it using Android 6.0 with root access (I was getting an error when using the command without root). I had to restart the phone for the setting to take effect.