How do I convert an integer to a string in gnuplot?

Question

I know how to use $ with using in examples like

plot datafile using f($1):g($2)

to plot functions of column data. But

Answer 1

set title sprintf("Polinômio de Taylor no ponto %f ",a)

or the English variant

set title sprintf("Taylor Polynomial at the point %f ",a)

will define the title transforming the number a into the previous string I have use this in a loop, with the Taylor Polynomial calculated previously at the point a, where a containing a number is the governing variable of the while.