Support for Console I/O (Printing) - 2023.1 English - UG1399

Using the C++ Standard Output Stream

The easiest way to output any value stored in an ap_[u]int variable is to use the C++ standard output stream:

std::cout (#include <iostream> or <iostream.h>)

The stream insertion operator (<<) is overloaded to correctly output the full range of values possible for any given ap_[u]fixed variable. The following stream manipulators are also supported:

• dec (decimal)
• hex (hexadecimal)
• oct (octal)

These allow formatting of the value as indicated.

The following example uses cout to print values:

#include <iostream.h>
// Alternative: #include <iostream>

ap_ufixed<72> Val(“10fedcba9876543210”);

cout << Val << endl; // Yields: “313512663723845890576”
cout << hex << val << endl; // Yields: “10fedcba9876543210”
cout << oct << val << endl; // Yields: “41773345651416625031020”

Using the Standard C Library

You can also use the standard C library (#include <stdio.h>) to print out values larger than 64-bits:

1. Convert the value to a C++ std::string using the ap_[u]fixed classes method to_string().
2. Convert the result to a null-terminated C character string using the std::string class method c_str().

Optional Argument One (Specifying the Radix)

You can pass the ap[u]int::to_string() method an optional argument specifying the radix of the numerical format desired. The valid radix argument values are:

• 2 (binary) (default)
• 8 (octal)
• 10 (decimal)
• 16 (hexadecimal)

Optional Argument Two (Printing as Signed Values)

A second optional argument to ap_[u]int::to_string() specifies whether to print the non-decimal formats as signed values. This argument is boolean. The default value is false, causing the non-decimal formats to be printed as unsigned values.

The following examples use printf to print values:

ap_int<72> Val(“80fedcba9876543210”);

printf(“%s\n”, Val.to_string().c_str()); // => “80FEDCBA9876543210”
printf(“%s\n”, Val.to_string(10).c_str()); // => “-2342818482890329542128”
printf(“%s\n”, Val.to_string(8).c_str()); // => “401773345651416625031020” 
printf(“%s\n”, Val.to_string(16, true).c_str()); // => “-7F0123456789ABCDF0”