The ugliness of the C-style formatting string in all its glory exhibited!!! Why TMW didn't go to the trouble to keep Fortran FORMAT instead. :(
Anyways, don't do this...do something like
fmt=['%f' repmat('%q',1,45) repmat('%f',1,2) repmat('%q',1,3) repmat('%f',1,2) ...
where continue to build the counted substrings as needed in place of "..." placeholders above.
The answer to the actual Q? asked is the line continuation syntax in Matlab is "...". For string continuation, must terminate the pieces on each line and let the input parser string them together; the above syntax encloses the actual strings excepting the first and last unique entries as the argument to the repmat function.
PS. Thanks to SL, TMW for illustrating this idiom years ago... :)