In several instances of the Camino code already implemented in NiPype, strings were used with the Float Trait so since it it worked this way (float numbers are correctly parsed) i corrected the error  above using %d in the same way (%d would not parse the number correctly, all decimal digits would be missing).

Could someone explain why strings were used for the Float trait in several instances? Is that to do with special notations such as 0.5E-04 ?