Predefined cross sections stored in a csv- or bin-database can be used to generate lists of cross sections via the “ReadCSTable”-component (see fig. 188.8.131.52). It works along the same lines as the “ReadMatTable” (see section 3.4.3) component. When given no path to a valid table “ReadCSTable” uses the list of cross sections comes with Karamba3D and is situated in “…/Grasshopper/Libraries/Karamba/CrossSectionValues.bin”. This table contains definitions for a range of standard steel profiles. Depending on the given file extension the data is expected to be either in binary format (“.bin”) or comma separated values (“.csv”). The former has the advantage of fast processing, the latter can be viewed and extended using a text editor or OpenOffice. In csv-files “#” is used to mark the rest of a line as comment. The physical units are always assumed to be metric – irrespective of the user settings at installation. In case of an entry in a csv-file in the first column which is not a “#”, the cross section properties get calculated based on the geometric dimensions of the cross section. In case of a deviation between the given and the calculated values of more than 10 % a warning is output at the “Info”-plug.
When opening the Karamba3D installation folder (double-click on the Karamba3D desktop icon for that) you will find three differently named cross section tables: “CrossSectionValues.bin” and “CrossSectionValues_sortedForHeight.bin” contain cross sections sorted according to increasing height. In “CrossSectionValues_sortedForWeight.bin” the area and thus weight per unit of length determines a cross sections relative position within a family. When doing cross section optimization (see section 3.5.8) those two sorting options lead to different results. Depending on external requirements they result in structures of minimum cross section height or structural weight.