sprintf

                                    #include <stdio.h>
#include <math.h>

int main () {
   char str[80];

   sprintf(str, "Value of Pi = %f", M_PI);
   puts(str);
   
   return(0);
}

                                    
There are already some comments on using sprintf to force leading leading zeros but the examples only include integers. I needed leading zeros on floating point numbers and was surprised that it didn't work as expected.

Example:
<?php
sprintf('%02d', 1);
?>

This will result in 01. However, trying the same for a float with precision doesn't work:

<?php
sprintf('%02.2f', 1);
?>

Yields 1.00. 

This threw me a little off. To get the desired result, one needs to add the precision (2) and the length of the decimal seperator "." (1). So the correct pattern would be

<?php
sprintf('%05.2f', 1);
?>

Output: 01.00

Please see http://stackoverflow.com/a/28739819/413531 for a more detailed explanation.

                                    int sprintf(char *str, const char *format, ...)

Parameters:

str − This is the pointer to an array of char elements where the resulting C string is stored.

format − This is the String that contains the text to be written to buffer. It can optionally contain embedded format tags that are replaced by the values specified in subsequent additional arguments and formatted as requested. Format tags prototype: %[flags][width][.precision][length]specifier

EXAMPLE:

#include <stdio.h>
#include <math.h>

int main () {
   char str[80];

   sprintf(str, "Value of Pi = %f", M_PI);
   puts(str);
   
   return(0);
}

OUTPUT:

Value of Pi = 3.141593

                                    <?php
$num = 5;
$location = 'tree';

$format = 'There are %d monkeys in the %s';
echo sprintf($format, $num, $location);