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interval_sample_sat¶

Run in Google Colab

View source on GitHub

First, you must install ortools package in this colab.

In [ ]:

%pip install ortools

Code sample to demonstrates how to build an interval.

In [ ]:

from ortools.sat.python import cp_model


def interval_sample_sat():
    """Showcases how to build interval variables."""
    model = cp_model.CpModel()
    horizon = 100

    # An interval can be created from three affine expressions.
    start_var = model.new_int_var(0, horizon, "start")
    duration = 10  # Python cp/sat code accept integer variables or constants.
    end_var = model.new_int_var(0, horizon, "end")
    interval_var = model.new_interval_var(start_var, duration, end_var + 2, "interval")

    print(f"interval = {repr(interval_var)}")

    # If the size is fixed, a simpler version uses the start expression and the
    # size.
    fixed_size_interval_var = model.new_fixed_size_interval_var(
        start_var, 10, "fixed_size_interval_var"
    )
    print(f"fixed_size_interval_var = {repr(fixed_size_interval_var)}")

    # A fixed interval can be created using the same API.
    fixed_interval = model.new_fixed_size_interval_var(5, 10, "fixed_interval")
    print(f"fixed_interval = {repr(fixed_interval)}")


interval_sample_sat()