c - Why sciencific notation for "(double)123456" with "%.4g" conversion is "1.235e+05" instead of 1.234e+05 -

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for me, seems normal 1.234e+05 when using conversion, because when revert '"%f\n", 1.235e+05' 123500.000000 instead of wished "123400.000000".

actually question is: why skipped "4" digit ?!

following example reinforces wanted say:

#include <stdio.h>  int main(int argc, char **argv) {     char x[100];     sprintf(x, "%.4g", (double)123456);     printf(">%s<\n", x);     printf("%f\n", 1.235e+05);     return 0; }

thanks, valentin

printf limited precision not truncate; rounds per current rounding mode. default mode round-to-nearest. since 123456 closer 123500 123400, former value printed.


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