Simple use of sprintf - C

Question

I\'m trying to work out why a larger problem is occurring, using a smaller program as an example. This smaller program does not work, leading me to believe it is my understa

Answer 1

This is because 5 is an integer (int), and you're telling sprintf to pretend that it's a double-precision floating-point number (double). You need to change this:

sprintf(word,"%.9g", 5);

to either of these:

sprintf(word,"%.9g", 5.0);
sprintf(word,"%.9g", (double) 5);

Answer 2

Use 5.0 instead. 5 by itself is an integer and will get bitmangled into looking like a float, which is where your 7.xxxx comes from.

Answer 3

I see two problems:

1. As others already said, you have to specify a double instead of an int. Your compiler may have a switch to print out warnings in these cases (-Wall in gcc, for example).

2. To print out 5.00..., you should use %f instead of %g.

That gives sprintf(word,"%.9f", (double) 5); as correct syntax.

Answer 4

Or you can change the descriptor format: "%.9d"