Description
Return complementary insertion and preservation masks.
Bit positions are usually counted from the least-significant bit, while a displayed binary string has its own left-to-right indexing convention. Masks, fields and parity predicates describe a selected region or pattern; local agreement does not validate a complete encoded record.
Return complementary insertion and preservation masks.
When to use this tool
Use Bitfield Insert Preservation Mask when checking the stated mask, field, parity or bit-index convention.
How to use the tool and how it works
- Enter width, offset, length. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read preservationMask, insertionMask. Use the output convention below.
Return complementary insertion and preservation masks. Require width 1..128 and a nonempty field within it; insertionMask is length low ones shifted by offset, preservationMask is its width-limited complement.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| width | Width under the stated bit, interval or geometry convention; apply the field-specific units and bounds. | Required. Safe integer; minimum 1; maximum 128. |
| offset | Offset | Required. Safe integer; minimum 0. |
| length | Length | Required. Safe integer; minimum 1. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| preservationMask | Preservation Mask | Required. Text; maximum UTF-16 length 8192. |
| insertionMask | Insertion Mask | Required. Text; maximum UTF-16 length 8192. |
{
"input": {
"width": 8,
"offset": 2,
"length": 3
},
"output": {
"preservationMask": "227",
"insertionMask": "28"
}
}Limitations and assumptions
- These are masks only, without a source field, insertion value or actual word mutation.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Choose an explicit bit order, word width and missing-position policy; use the complete record format and appropriate parsing or checksum methods for full validation.
References
Similar or alternative tools
- Bitfield Offset Alignment Remainder
Return offset alignment remainder and required padding.
- Bitwise: Bitfield Width From Endpoints
Return field width from inclusive bit endpoints.