--- name: "ldc" section: "3bobcat" platform: "linux" package: "libbobcat-dev" version: "6.07.01-2" release: "Debian 13 (Trixie)" platforms: ["linux"] url: "https://new.carta.tech/ldc/3bobcat" --- # ldc(3bobcat) Converts (large) digital values to characters ## NAME FBB::LDC - Converts (large) digital values to characters ## SYNOPSIS **#include \**\ Linking option: *-lbobcat* ## DESCRIPTION Objects of the class *LDC* (Large Digital Converter) convert (large) digital values (like values handled by the class *BigInt* (cf. [**bigint**(3bobcat)](/bigint/3bobcat.md))) to character representations using radices from 2 through 36. For radices larger than 10 letters are used, using *a* through *z* to represent the (decimal) values 10 through 36. When specifying radices outside of this range an exception is thrown. Alternatively, the digits of the converted number can be provided in a *std::string* argument, where the string’s first character (at index 0) is used for value 0, the next character for value 1, etc., until the string’s last character. In that case the string’s length defines the number system that is used for converting the (large) digital value. Usually the first 10 characters will be *"0123456789"*, but LDC doesn’t enforce that. Instead, any series of characters can be specified, in which case the character at index *idx* is used to represent value *idx* in the converted value string. E.g., when specifying *"abcdefghij"* the hexadecimal value *"deadbeef"* is converted to *"dhdfjciffj"* instead of *"3735928559"*, which is the normally used decimal digit representation. Digit strings must at least contain two characters or an exception is thrown. ## NAMESPACE **FBB**\ All constructors, members, operators and manipulators, mentioned in this man-page, are defined in the namespace **FBB**. ## INHERITS FROM \- ## CONSTRUCTORS - o **LDC()**:\ The default constructor initializes its value to 0; - - o **LDC(std::string const &hexNr, size\_t radix = 10)**:\ The bytes of the string *hexNr* contains the character representation of a hexadecimal value, which is converted to its equivalent representation using the *radix* number system. The string *hexNr* should not begin with *0x*, but its first character should be the value’s most significant digit. E.g., *LDC ldc{ "12345" }* is converted to decimal 74565 (in this example *"12345"* is first converted to a *std::string*, which is then passed on to *ldc’s* constructor). *hexNr* may not be empty or an exception is thrown; - - o **LDC(std::string const &hexNr, std::string const &digits)**:\ Same as the previous constructor, but the number system is inferred from *digits’s* length, using its first character to represent value 0, and its last character to represent the final digit of the inferred number system; - - o **LDC(size\_t nBytes, char const \*bytes, size\_t radix = 10)**:\ The bytes of the string *bytes* contains the character representation of a hexadecimal value, which is converted to its equivalent representation using *radix*. The string *bytes* should not begin with *0x*, but its first character should be the value’s most significant digit. E.g., *LDC{ 5, "12345" }* is converted to decimal 74565. *nBytes* must be at least 1 or an exception is thrown; - - o **LDC(size\_t nBytes, char const \*bytes, std::string const &digits)**:\ Same as the previous constructor, but the number system and the digit characters are inferred from *digits*; - - o **LDC(BigInt const &bigInt, size\_t radix = 10)**:\ *BigInt’s* value is converted to its equivalent representation using *radix*; - - o **LDC(BigInt const &bigInt, std::string const &digits)**:\ Same as the previous constructor, but the number system and the digit characters are inferred from *digits*. Copy and move constructors (and assignment operators) are available. ## OVERLOADED OPERATORS In addition to the standard copy- and move-assignment operators the following operators are available: - o **LDC &operator=(std::string const &hexNr)**:\ The operator’s rhs is the character representation of a hexadecimal number, which is assigned to the *LDC* object. The object converts *hexNr* to its decimal representation (see also the members *set*, below).\ Example: ``` LDC ldc; // initialized with some value ldc = "12345"; // assign a new value cout << ldc << ’\n’ // displays 74655 ``` The rhs value may not be empty or an exception is thrown; - - o **std::string operator()(size\_t power, char sep = ’\\’’) const**:\ The converted value is returned using separator *sep* before each multiple of *power* digits. E.g., when *ldc* contains the converted value *3735928559* then *ldc(3)* returns the string *3.735.928.559*. ## FREE FUNCTION IN THE FBB NAMESPACE - o **std::ostream &operator\<\<(std::ostream &out, LDC const &ldc)**:\ The insertion operator inserts the converted value into *out*, returning *out*. ## MEMBER FUNCTIONS - o **void set(std::string const &hexNr, size\_t radix = 10)**:\ The *LDC* object’s converted value is set to the hexadecimal value *hexNr*, converted to number system *radix*. *hexNr* may not be empty or an exception is thrown ; - - o **void set(std::string const &hexNr, std::string const &digits)**:\ Same as the previous member, but converting *hexNr* to the number system and number characters defined by *digits*; - - o **void set(size\_t nBytes, char const \*bytes, size\_t radix = 10)**:\ The *LDC* object’s converted value is set to the hexadecimal value stored in the *nBytes* bytes of *bytes*, converted to number system *radix*. *nBytes* must be at least 1 or an exception is thrown; - - o **void set(size\_t nBytes, char const \*bytes, std::string const &digits)**:\ Same as the previous member, but converting *bytes* to the number system and number characters defined by *digits*; - - o **std::string const &str() const**:\ The *LDC* object’s converted value is returned; - - o **void swap(LDC &other)**:\ The *other* LDC object and the current *LDC* object are swapped. ## EXAMPLE ``` #include #include using namespace std; using namespace FBB; int main(int argc, char **argv) { string value = "1122334455667788aabbcc"; size_t radix = 10; LDC digits{ value, "0123456789ABCDEF" }; LDC ldc{ value, radix }; cout << "radix = " << radix << "\n" "value = " << value << "\n" "digits: " << digits << "\n" " LDC: " << ldc << "\n" " " << ldc(3, ’.’) << ’\n’; } // shows: // radix = 10 // value = 1122334455667788aabbcc // digits: 1122334455667788AABBCC // LDC: 20713245101768454273940428 // 20.713.245.101.768.454.273.940.428 ``` ## FILES *bobcat/ldc* - defines the class interface ## SEE ALSO [**bobcat**(7)](/bobcat/7.md) ## BUGS None Reported. ## BOBCAT PROJECT FILES - o *https://fbb-git.gitlab.io/bobcat/*: gitlab project page; Debian Bobcat project files: - o *libbobcat6*: debian package containing the shared library, changelog and copyright note; - o *libbobcat-dev*: debian package containing the static library, headers, manual pages, and developer info; ## BOBCAT Bobcat is an acronym of \`Brokken’s Own Base Classes And Templates’. ## COPYRIGHT This is free software, distributed under the terms of the GNU General Public License (GPL). ## AUTHOR Frank B. Brokken (**f.b.brokken@rug.nl**).