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digitalmars.D.learn - "%a" formatting differences

reply bearophile <bearophileHUGS lycos.com> writes:
Do you know what's causing the difference in the outouts?

void main() {
  double d1 = 3.14159;
  printf("%a\n", d1);
  writefln("%a\n", d1);
}

Outputs:
0x1.921f9f01b866ep+1
0xc.90fcf80dc337p-2

A printf in C code compiled with GCC prints the same as the printf here.

Bye,
bearophile
Dec 14 2009
parent reply BCS <none anon.com> writes:
Hello bearophile,


 Do you know what's causing the difference in the outouts?
 
 void main() {
 double d1 = 3.14159;
 printf("%a\n", d1);
 writefln("%a\n", d1);
 }
 Outputs:
 0x1.921f9f01b866ep+1
 0xc.90fcf80dc337p-2
 A printf in C code compiled with GCC prints the same as the printf
 here.
 
 Bye,
 bearophile



Just a guess: D is correctly using double and C is assuming float? Try running 
it with d1 as a float to check.
Dec 14 2009
parent bearophile <bearophileHUGS lycos.com> writes:
BCS:

 Just a guess: D is correctly using double and C is assuming float? Try running 
 it with d1 as a float to check.



I have run the code again with the last D1 compiler, and now writeln is giving
the same result as printf. So probably it was a writefln bug that's already
fixed.
Sorry for the useless noise -.-

Bye,
bearophile
Dec 14 2009