Showing posts with label Type B. Show all posts
Showing posts with label Type B. Show all posts

Monday, August 15, 2011

New version of EulumdatTools 0.9.4.v20110729 available

A new version of EulumdatTools 0.9.4.v20110729 was published today at http://www.fold1.com/eulumdattools/. We added the conversion of Type B photometry IES files to EULUMDAT to the existing conversion of Type C files. We also hardened the parser so more files with errors can be opened and displayed, so they can be corrected. We extended the hardcoded expiry date of this release to well in 2012.

Some background theory

The photometric intensity distribution in EULUMDAT files is similar to that a Type C IES file. The center of beam is straight down (or up) and there are vertical (IES: lateral) planes rotating around this central down axis. In each vertical (IES: lateral) plane there are a number of vertical angles. For more info see AGI32 website.

Trigonometric conversions

To determine the intensity at a pair of the C and γ angles, we need to interpolate at a corresponding pair of B and β angles. The corresponding B and β angles can be found using these formulas:
tan B = cos C * tan γ
sin β = sin C * sin γ
We added some extra logic to handle the determination of the right quadrant.

Interpolation used

Interpolation is done using standard lagrange over 3 planes and then over the 3 resulting points.

More info

See this book for more details.

Installation

For use in Eclipse you can use the standard Eclipse update site http://www.fold1.com/eulumdattools/. For stand alone RCP versions of EulumdatTools choose your platform:

Friday, July 22, 2011

New online IES to EULUMDAT Converter now also handles Type B photometry

A new version of the free online IES to EULUMDAT Converter was published today at http://ies2eulumdat.appspot.com/.

We added the conversion of Type B photometry IES files to EULUMDAT to the existing conversion of Type C files.

Some background theory

The photometric intensity distribution in EULUMDAT files is similar to that a Type C IES file. The center of beam is straight down (or up) and there are vertical (IES: lateral) planes rotating around this central down axis. In each vertical (IES: lateral) plane there are a number of vertical angles. For more info see AGI32 website.

Trigonometric conversions

To determine the intensity at a pair of the C and γ angles, we need to interpolate at a corresponding pair of B and β angles. The corresponding B and β angles can be found using these formulas:

tan B = cos C * tan γ

sin β = sin C * sin γ

We added some extra logic to handle the determination of the right quadrant.

Interpolation used

Interpolation is done using standard lagrange over 3 planes and then over the 3 resulting points.

More info

See this book for more details.