Description
Sample uniformly over monotone route move sequences by choosing down-step positions; no obstacle pathfinding, speed or geometric shortest-path guarantee beyond grid moves.
A random construction is defined by its sampling support: positions, permutations, complete tilings, proposal sequences or another explicit set. Uniform choices at one stage do not necessarily make final visible outcomes uniform. A replay seed gives a deterministic sequence; equal values can hide different sampled positions. These tools are for reproducible synthetic examples rather than cryptographic entropy.
Sample uniformly over monotone route move sequences by choosing down-step positions; no obstacle pathfinding, speed or geometric shortest-path guarantee beyond grid moves.
When to use this tool
Use this tool to sample uniformly over monotone route move sequences by choosing down-step positions; no obstacle pathfinding, speed or geometric shortest-path guarantee beyond grid moves.
How to use the tool and how it works
- Enter right, down, seed using the definitions below.
- Run the operation. Resolve input-format errors before interpreting an output.
- Read result.seed, result.moves, result.points, result.support, using the stated boundary, ordering, sign and absence conventions.
Require positive total right+down steps no greater than 127. Choose the down-step positions uniformly without replacement, fill other slots with right and accumulate grid points from [0,0]. Return C(right+down,down) as exact support text.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| right | Integer number of right moves, 0–127; right+down must be 1–127. | Finite safe integer satisfying the stated bounds. |
| down | Integer number of down moves, 0–127; combined move count must be 1–127. | Finite safe integer satisfying the stated bounds. |
| seed | Nonblank replay seed, at most 256 UTF-16 code units; an injected source overrides seeded draws. | Text, at most 8,192 UTF-16 code units; narrower grammar/range rules also apply. |
| Output field | Interpretation |
|---|---|
| result | Object containing the fields below. |
| result.seed | Original supplied seed string; injected-source replay additionally requires that source’s state. |
| result.moves | Generated right/down move labels in route order. |
| result.points | Route vertices including the initial [0,0] and final endpoint. |
| result.support | Exact finite support count as decimal text. |
{
"input": {
"right": 2,
"down": 1,
"seed": "batch56"
},
"output": {
"result": {
"seed": "batch56",
"moves": [
"right",
"down",
"right"
],
"points": [
[
0,
0
],
[
1,
0
],
[
1,
1
],
[
2,
1
]
],
"support": "3"
}
}
} Limitations and assumptions
- All routes are monotone in positive right/down coordinates; there is no obstacle, wrap or shortest-path search beyond this fixed move bank.
- A nonblank seed of at most 256 UTF-16 code units is required. With ordinary use the seed initializes one deterministic advancing source; an application-injected random source takes precedence and the seed alone then cannot replay the result. Uniformity statements assume independent uniform source draws in [0,1). Source calls are bounded and degenerate injected sources can fail a rejection budget. This is not cryptographically secure.
- Every declared outer field is required and unknown outer fields are rejected. Strings and JSON text have size limits, lists are bounded to 128 entries, and JSON nesting/node counts are bounded. Tighter operation-specific bounds stated above take precedence.
- Ordinary numeric outputs must be finite and within safe-integer magnitude. Exact large lengths/counts use decimal strings. Original record indexes and code-unit positions are zero-based; span ends are exclusive unless stated otherwise.
Alternative or Complementary methods
Choose a generator whose support matches the intended experiment and retain source-position provenance. Use a separate statistically justified process model or cryptographic source where those properties matter.
References
Similar or alternative tools
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