test_opt.py 文件源码

def test_abs_mul_div(self):
        """
        test that if we have
        4 * x / abs(2*x) it get simplifier during canonicalisation.
        """

        x = T.dscalar()
        a = T.abs_(x)

        if theano.config.mode == 'FAST_COMPILE':
            mode = theano.compile.mode.get_mode('FAST_RUN').excluding(
                    "local_elemwise_fusion")
        else:
            mode = theano.compile.mode.get_default_mode().excluding(
                    "local_elemwise_fusion")

        f = theano.function([x], [(4 * x) / abs(2 * x)], mode=mode)
        print(f.maker.fgraph.toposort())
        print()
        f(.1)
        f(-1)
        # some stabilization optimization make the output be finite instead of nan
        # debug_mode will raise an error when he see nan
        if not isinstance(mode, theano.compile.debugmode.DebugMode):
            assert numpy.isfinite(f(0))

        assert len(f.maker.fgraph.toposort()) == 2
        assert f.maker.fgraph.toposort()[0].op == T.sgn

        f = theano.function([x], [(4 * x) / abs(x / 2)], mode=mode)
        print(f.maker.fgraph.toposort())
        print()
        f(.1)
        f(-1)
        # some stabilization optimization make the output be finite instead of nan
        # debug_mode will raise an error when he see nan
        if not isinstance(mode, theano.compile.debugmode.DebugMode):
            assert numpy.isfinite(f(0))

        assert len(f.maker.fgraph.toposort()) == 2
        assert f.maker.fgraph.toposort()[0].op == T.sgn