Stack Overflow
Stack Overflow

Questions tagged [bitflags]

the use of individual bits in a byte (or a set of bytes) to represent boolean values.

119 questions
2
votes
3 answers

Bit manipulation and Flags testing in C

Suppose I have two variables of type int, a and b, and a flag F. #define F int a = ; int b = ; What is a simple way to test that both a and b, have the flag F, or none of them has it? To test if both of them…
Bite Bytes
  • 1,455
  • 8
  • 24
2
votes
1 answer

C++ bitmap to hold binary flags

the problem is this: I need to create a bitmap (a series of binary flags) to hold true/false information about a bunch of objects; the number of object is not known a priori so I have to allocate enough flags at runtime, possibly during the bitmap…
fudo
  • 2,254
  • 4
  • 22
  • 44
2
votes
2 answers

What to name an array of flags?

I have a project where lots of the objects hold state by maintaining simple boolean flags. There are lots of these, so I maintain them within a uint32_t and use bit masking. There are now so many flags to keep track of, I've created an abstraction…
Chris Tonkinson
  • 13,823
  • 14
  • 58
  • 90
2
votes
1 answer

Failing to use the FlagsAttribute on an enum (Cannot resolve symbol 'HasFlag')

I have an asmx web service in c# and have recently discovered the very useful FlagsAttribute for enums. My declaration is as follows: [Flags] public enum eAdPriority { None = 0, Gold = 1, Silver = 2, Homepage = 4 } I then test the…
Jimbo
  • 22,379
  • 42
  • 117
  • 159
2
votes
4 answers

Check if Flags Enum containts all strings

I have the following flags Enum: [Flags] public enum RoleModels { Master = 1 << 0, Editor = 1 << 1, Member = 1 << 2 } And I have a RoleModels variable and a list of strings: var roles1 = RoleModels.Master | RoleModels.Member; List…
Miguel Moura
  • 36,732
  • 85
  • 259
  • 481
2
votes
4 answers

Bitflag enums in C++

Using enums for storing bitflags in C++ is a bit troublesome, since once the enum values are ORed they loose their enum-type, which causes errors without explicit casting. The accepted answer for this question suggests overloading the |…
sold
  • 2,041
  • 5
  • 25
  • 32
2
votes
5 answers

Determine Position of Most Signifiacntly Set Bit in a Byte

I have a byte I am using to store bit flags. I need to compute the position of the most significant set bit in the byte. Example Byte: 00101101 => 6 is the position of the most significant set bit Compact Hex Mapping: [0x00] => 0x00 [0x01] …
recursion.ninja
  • 5,377
  • 7
  • 46
  • 78
2
votes
0 answers

PHP/MySQL Field/Column Bit-Flags: UNIQUE_KEY_FLAG vs. UNIQUE_FLAG

In PHP, when extracting bit-flags from MySQL columns/fields, I see (from other SO answers): UNIQUE_KEY_FLAG = 4 UNIQUE_FLAG = 65536 I'm wondering what the difference is between these two bit-flags? And why do the lists that I do find show both…
Keith DC
  • 661
  • 1
  • 9
  • 24
1
vote
2 answers

Is it possible to check for exactly n flags are set for an enum in C++ std::unordered_map key?

I am setting up an unordered_map, in which the key is an enum of Direction defined as: enum Direction : uint16_t { North = 1 << 0, East = 1 << 2, South = 1 << 3, West = 1 << 4, None = 1 << 5, }; The goal is to check if at least…
Ian
  • 65
  • 1
  • 8
1
vote
1 answer

Deserializing a bitflag enum in C# with Unity

I have a unity project. Using the stock json tools at my disposal, i'm trying to deserialize an enum that uses bit flags (ie something like) [Flags] enum Terrain { NORMAL = 0, FOREST = 1, SWAMP = 2, CAVE = 4 } In json it's something like…
nuk
  • 39
  • 6
1
vote
2 answers

Can I decompose a Python Flag enum into its fundamental parts?

I have an enum that represents the directions you're allowed to move for a given cell in a maze: class Direction(Flag): NORTH = 1 EAST = 2 SOUTH = 4 WEST = 8 NE = NORTH | EAST NW = NORTH | WEST ...etc NESW = NORTH |…
codebreaker
  • 763
  • 1
  • 7
  • 24
1
vote
1 answer

Why cout.flags() & std::ios_base::right prints 0 even though by default the output is right aligned

I am learning C++'s iostream. In particular, I have learnt that by default the output of cout is right aligned. For example, if I write: #include #include int main() { std::cout << setw(10) << "abb" ; //this is guaranteed to…
Alex
  • 318
  • 1
  • 14
1
vote
1 answer

Groupby and Count Flags as indexes in Pandas

I have a dataframe which has flags 0/1 for multiple products along with accounts and which zipcode they belong to. My Goal is to count the 1's in columns which have been created as flags. Zip acc A B 32123 214124 1 0 32123…
m2rik
  • 135
  • 7
1
vote
5 answers

searching bit-field templates (codebooks)

I've got a bunch of 8-bit values in a codebook (about 200 of them). My program will be generating an 8-bit value in response to input, and I need to find all (or even the first is helpful) of the matches in the codebook that have the same bits set.…
akevan
  • 691
  • 1
  • 9
  • 21
1
vote
1 answer

How to store Processor Status flags' values with corresponding enum for 6502

I'm working on 6502 emulator in C++ as a part of my thesis. It has 6 registers, most of them just hold values but there's one special - Processor Status. It's 8 bit wide and each bit means a different flag. The best choice for me seemed to make it…
Sebastian Kucharzyk
  • 85
  • 7
1 2 3
4
5 6 7 8