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Random Constraint Generator

This process is used to generate sets of random flux constraints. There are many conceivable ways to create random flux constraints, but this process uses only one such technique.

Each set of randomly generated flux constraints will be of size n. Some number of fluxes, k, in each set will be "active", and some number of fluxes, n-k, will be "inactive". The assignment of "active" or "inactive" is randomly chosen for each flux in each generated set. The value of n is equal to the number of reactions specified as data headers, and the value of k must be provided. The intervals used to represent active and inactive fluxes must be specified as well.

Here is the set of keywords this process understands, along with a description of their possible corresponding values. See the command line documentation for more information about keyword-value pairs.


Required Keywords Possible Values
Process FBA Random Constraint Generator
Reaction File The name of an FBA Reaction File containing a stoichiometric network.
Iterations The number of sets of constraints to be generated.
Seed The seed for the random number generator.
Number of Active Fluxes The number of active fluxes per set.
Reversible Constraint The interval used to define the flux constraints for active reversible reactions.
Irreversible Constraint The interval used to define the flux constraints for active irreversible reactions.
Inactive Constraint The interval used to define the constraint for inactive fluxes.
Data Headers The reaction name data headers of the output file.
Output File Name The desired name of the constraint variation file to be created.

Examples

Click here for an example.