# Regular Expressions in Conversion Files

### Tips & Tricks

001139 5 November 2015

RFEM and RSTAB provide numerous interfaces with other programs for data exchange. In the respective programs, different names are often used for the same materials and cross‑sections. Therefore, it is necessary to convert the material and cross‑section names in order to be recognized by the program after the data exchange.

For the conversion, it is possible to use a conversion file. In addition to specifying a name in another programs and describing it accordingly in RFEM/RSTAB as explained in the post Simplified Import and Export via Conversion File, you can use regular expressions for the conversion. In each case, it is necessary to define the conversion for importing (to RFEM/RSTAB) and exporting (from RFEM/RSTAB). For this, the following syntax is required:

Import format:
REGEX_IMP: Example material or cross‑section; Example alternative material or cross‑section

Export format:
REGEX_EXP: Example material cross‑section; Example alternative material or cross‑section

For example:
There is the following conversion to be done:
Pi(B) 500/20/15/300/400/100/12/4/3 <--> ZHWS400*500*15*20*100*12*300
REGEX_IMP:^ZHWS(\d+)\*(\d+)\*(\d+)\*(\d+)\*(\d+)\*(\d+)\*(\d+); Pi(B) $2/$4/$3/$7/$1/$5/$6/0/0 REGEX_EXP:^Pi$B$\s?(\d+)/(\d+)/(\d+)/(\d+)/(\d+)/(\d+)/(\d+)/(\d+)/(\d+); ZHWS$5*$1*$3*$2*$6*$7*$4