12. MERLIN Toolkit

12. MERLIN Toolkit

MERLIN Toolkit is supplied free with MERLIN and MERLINPLUS, but can also be purchased on its own by non-MERLIN users.

Its main function is to provide a user-friendly bridge between MERLIN and other software packages so – for example – a MERLIN user can import from a web interviewing package (via Triple-S), or export to SPSS. Someone not using MERLIN, however, can get from the web interviewing package to SPSS without doing any MERLIN processing in between, or convert from one Triple-S version to another. For a full list of MERLIN Toolkit imports and exports, refer to the Survey Software section of our website.

This blog, however, concentrates on the lesser known Tools menu, which contains a number of useful utilities.

Tools menu


Join data files vertically / horizontally

These utilities combine separate data files into one, and can be used with ASCII, CSV or “cba” (column binary) data.

Vertical Join simply places all the records from separate files into a single file – whether for convenience, or because you are using software that requires this.

Horizontal Join is used to combine records that belong to the same respondent, but are held in separate files with matching keys – e.g. pre-coded and open-ended data with matching serial numbers can be combined into a single file (typically by adding the open-ended data on the end of the pre-coded records). The user can choose whether or not to include unmatched records from either file.


Join Excel tables files vertically / horizontally

These utilities combine separate Excel files of MERLIN tables into a single volume – the original files having been generated with MERLIN Run Control Parameter XLSTAB set to 1 or 3. The files may be separate because they were generated at different times, or to overcome size limitations, or simply because it was more convenient – but you now wish to put all the tables in a single file

Vertical Join puts all the tables into a single volume without modification (except for renumbering them if required), and generates a new Table of Contents.

Horizontal Join is used with sets of tables that are identical apart from the banner (horizontal axis), and combines these separate banners into one.


Convert CSV/XLSX bitstrings to spreadfields

This utility reads a “csv” or “xlsx” data file in which the multi-coded variables are coded in bitstring format (e.g. 1,0,0,1,1 in separate fields), and outputs a new file of the same type in which these variables are in spreadfield format (e.g. “1,4,5” in a single field). This can greatly reduce the size of the file, overcome limits, and make it faster to process.

The utility works by examining the field names in the header row and looking for names containing at least one underscore character “_” and the last underscore (if more than one) is used to split the name into a prefix and a suffix. If consecutive fields have the same prefix, and all the cells in those fields contain 0, 1, space(s) or blank only, then those columns will be merged into one spreadfield with the prefix as the field name.

If, for example, the input file contains consecutive fields named Q5_A, Q5_B, Q5_C, Q5_D all containing 0, 1, space(s) or blank only, they will be replaced by a single field named Q5.



DMERGE is a utility for combining two or more “idf”s (MERLIN internal data files) into a single “idf”, whether or not they are compatible.

DMERGE is mainly used so MERLIN can analyse data from incompatible “idf”s – especially useful for merging data from several waves of a survey. It is also possible to select variables from each of the input “idf”s, so DMERGE could be used with a single input “idf” simply to output a new one with fewer variables.

The output “idf” will contain all the records from all the input “idf”s, and these new records will (by default) contain all the variables defined in any of the input “idf”s. Variables that are not defined in a particular “idf” will be empty.


Any questions? Email support@merlinco.co.uk.

2024 © Merlinco Survey Software & Analysis | Site by DDA