Created: 2023-01-11 11:18
Status: #concept
Subject: Programming
Tags: C stdio.h Format String

Precision

It’s the .p in the %m.pX placeholder to indicate specific formatting, depending on the Conversion Specifiers.

Example

printf("%10.2d\n", 3);
printf("%10.2e\n", 3.142f);
printf("%10.2f\n", 3.142f);
printf("%10.2g\n", 3.142f);

/*** OUTPUT ***/
        03
  3.14e+00
      3.14
       3.1

Precision Conversion Specifier.png

The g Conversion Specifier is useful when we are unsure whether the output will be big or small.

It will automatically use decimal points for small numbers & exponents for larger floating-point numbers, according to the amount of significant numbers specified by the precision.

References