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stochastic and stochastic-smp

stochastic is used to sample secondary structures from the Boltzman enemble. The probability of sampling a given structure is proportional to the probability that it occurs. stochastic-smp is a parallel processing version for use on multi-core computers, built using OpenMP.

USAGE: stochastic <input file> <ct file> [options]

OR: stochastic-smp <input file> <ct file> [options]

Required parameters:

<input file> The name of a file containing input data. This input data can be in one of two formats:
  1. Partition function save file (holds base pairing probability data for all pairs and can be generated using the partition interface).
  2. Sequence file (holds raw sequence: .seq or .fasta).
    Note that lowercase nucleotides are forced single-stranded in structure prediction.
    Note that in order to use a squence file, the "sequence" flag must be specified (see "--sequence" below).
<ct file> The name of a CT file to which output will be written.

Options that do not require added values:

-d, -D, --DNA This flag only matters if the input file is a sequence file and has been identified as such (see "--sequence" below).
Specify that the sequence is DNA, and DNA parameters are to be used.
Default is to use RNA parameters.
-h, -H, --help Display the usage details message.
--sequence Identify the input file format as a sequence file.

Options that require added values:

-e, -E, --ensemble Specify the ensemble sample size.
Default is 1000 structures.
-s, -S, --seed Specify the random number seed as an integer. Using a different seed will result in a different sample of structures.
Default is 1234.

Notes for smp:

stochastic-smp, by default, will use all available compute cores for processing. The number of cores used can be controlled by setting the OMP_NUM_THREADS environment variable.


  1. Reuter, J.S. and Mathews, D.H.
    "RNAstructure: software for RNA secondary structure prediction and analysis."
    BMC Bioinformatics, 11:129. (2010).
  2. Harmanci, A.O., Sharma, G. and Mathews, D.H.
    "Stochastic sampling of the RNA structural alignment space."
    Nucleic Acids Res., 37:4063-4075. (2009).
  3. Ding, Y. and Lawrence, C.E.
    "A statistical sampling algorithm for RNA secondary structure prediction."
    Nucleic Acids Res., 31:7280-7301. (2003).