---
name: "dayfact"
section: "1"
platform: "linux"
package: "radiance"
version: "4R1+20120125-1+b1"
release: "Debian 7 (Wheezy)"
platforms: ["linux"]
url: "https://new.carta.tech/dayfact"
---

# dayfact(1)

compute illuminance and daylight factor on workplane

## NAME

dayfact - compute illuminance and daylight factor on workplane

## SYNOPSIS

**dayfact** \[ falsecolor options \]

## DESCRIPTION

*Dayfact* is an interactive script for computing workplane illuminance, and daylight factors and potential daylight savings using *[rtrace(1)](/rtrace/1.md).* The script *[falsecolor(1)](/falsecolor/1.md)* is then used to draw contour lines on the resulting Radiance picture.

## AUTHOR

Greg Ward

## ACKNOWLEDGEMENT

Work on this program was initiated and sponsored by the LESO group at EPFL in Switzerland.

## SEE ALSO

[falsecolor(1)](/falsecolor/1.md), [glare(1)](/glare/1.md), [rtrace(1)](/rtrace/1.md), [ximage(1)](/ximage/1.md)