예제 #1
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    def test_multi_motif_embedding(self):
   
        motif_names = ["CTCF_known1", "IRF_known1",
                       "SPI1_known1", "CTCF_known2", "CTCF_disc1"] 
        loaded_motifs = sn.LoadedEncodeMotifs(simdna.ENCODE_MOTIFS_PATH,
                                   pseudocountProb=0.001)
        position_generator = sn.UniformPositionGenerator()
        embedders = [sn.SubstringEmbedder(sn.PwmSamplerFromLoadedMotifs(
                     loaded_motifs, motif_name),
                     position_generator, name=motif_name)
                     for motif_name in motif_names]
        min_selected_motifs = 1
        max_selected_motifs = 4
        quantity_generator = sn.UniformIntegerGenerator(min_selected_motifs,
                                                     max_selected_motifs)
        combined_embedder = [sn.RandomSubsetOfEmbedders(
                             quantity_generator, embedders)]
        embed_in_background = sn.EmbedInABackground(
            sn.ZeroOrderBackgroundGenerator(
             300, discreteDistribution={'A':0.3, 'C':0.2, 'G':0.2, 'T':0.3}),
            combined_embedder)
        generated_sequences = tuple(sn.GenerateSequenceNTimes(
            embed_in_background, 8000).generateSequences())
        sequence_arr = np.array([generated_seq.seq for
                                 generated_seq in generated_sequences])
        label_generator = sn.IsInTraceLabelGenerator(np.array(motif_names))
        y = np.array([label_generator.generateLabels(generated_seq)
                      for generated_seq in generated_sequences]).astype(bool)
        embedding_arr = [generated_seq.embeddings for generated_seq in generated_sequences]

        num_embeddings_count = defaultdict(lambda: 0)
        for seq, labels, embeddings, generated_seq in zip(sequence_arr, y, embedding_arr, generated_sequences):
            motifs_embedded = set()
            num_embeddings_count[len(embeddings)] += 1
            for embedding in embeddings:
                #assert that the string selected is correct
                assert embedding.what.string ==\
                        seq[embedding.startPos:
                            (embedding.startPos+len(embedding.what.string))]
                motifs_embedded.add(embedding.what.getDescription()) 
            assert len(motifs_embedded) == len(embeddings) #non-redundant
            for (motif_idx, motif_name) in enumerate(motif_names):
                if motif_name in motifs_embedded:
                    assert labels[motif_idx]==True
                else:
                    assert labels[motif_idx]==False
        
        #assert that the num selected is drawn correctly from a uniform dist
        for num_selected_motifs in range(min_selected_motifs,
                                         max_selected_motifs+1): 
            np.testing.assert_almost_equal(
        num_embeddings_count[num_selected_motifs]/float(len(sequence_arr)),
        1.0/(max_selected_motifs-min_selected_motifs+1),2)
        #there also shouldn't be a preference for any one motif over others
        np.testing.assert_almost_equal(
            np.sum(y,axis=0)/float(np.sum(y)), 1.0/len(motif_names), 2)
예제 #2
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def do(options):
    if (options.seed is not None):
        import numpy as np
        np.random.seed(options.seed)
        import random
        random.seed(options.seed)

    outputFileName_core = util.addArguments("DensityEmbedding", [
        util.ArgumentToAdd(options.prefix, "prefix"),
        util.BooleanArgument(options.bestHit, "bestHit"),
        util.ArrArgument(options.motifNames, "motifs"),
        util.ArgumentToAdd(options.min_motifs, "min"),
        util.ArgumentToAdd(options.max_motifs, "max"),
        util.ArgumentToAdd(options.mean_motifs, "mean"),
        util.FloatArgument(options.zero_prob, "zeroProb"),
        util.ArgumentToAdd(options.seqLength, "seqLength"),
        util.ArgumentToAdd(options.numSeqs, "numSeqs")
    ])

    loadedMotifs = synthetic.LoadedEncodeMotifs(options.pathToMotifs,
                                                pseudocountProb=0.001)
    Constructor = synthetic.BestHitPwmFromLoadedMotifs if options.bestHit else synthetic.PwmSamplerFromLoadedMotifs
    embedInBackground = synthetic.EmbedInABackground(
        backgroundGenerator=synthetic.ZeroOrderBackgroundGenerator(
            seqLength=options.seqLength),
        embedders=[
            synthetic.RepeatedEmbedder(
                synthetic.SubstringEmbedder(
                    synthetic.ReverseComplementWrapper(
                        substringGenerator=Constructor(
                            loadedMotifs=loadedMotifs, motifName=motifName),
                        reverseComplementProb=options.rc_prob),
                    positionGenerator=synthetic.UniformPositionGenerator()),
                quantityGenerator=synthetic.ZeroInflater(
                    synthetic.MinMaxWrapper(synthetic.PoissonQuantityGenerator(
                        options.mean_motifs),
                                            theMax=options.max_motifs,
                                            theMin=options.min_motifs),
                    zeroProb=options.zero_prob))
            for motifName in options.motifNames
        ])
    sequenceSet = synthetic.GenerateSequenceNTimes(embedInBackground,
                                                   options.numSeqs)
    synthetic.printSequences(outputFileName_core + ".simdata",
                             sequenceSet,
                             includeFasta=True,
                             includeEmbeddings=True,
                             prefix=options.prefix)
예제 #3
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def motif_density(motif_name,
                  seq_length,
                  num_seqs,
                  min_counts,
                  max_counts,
                  GC_fraction,
                  central_bp=None):
    """
  Returns sequences with motif density, along with embeddings array.
  """
    import simdna
    from simdna import synthetic
    loaded_motifs = synthetic.LoadedEncodeMotifs(simdna.ENCODE_MOTIFS_PATH,
                                                 pseudocountProb=0.001)
    substring_generator = synthetic.PwmSamplerFromLoadedMotifs(
        loaded_motifs, motif_name)
    if central_bp is not None:
        position_generator = synthetic.InsideCentralBp(central_bp)
    else:
        position_generator = synthetic.UniformPositionGenerator()
    quantity_generator = synthetic.UniformIntegerGenerator(
        min_counts, max_counts)
    embedders = [
        synthetic.RepeatedEmbedder(
            synthetic.SubstringEmbedder(
                synthetic.ReverseComplementWrapper(substring_generator),
                position_generator), quantity_generator)
    ]
    embed_in_background = synthetic.EmbedInABackground(
        synthetic.ZeroOrderBackgroundGenerator(
            seq_length, discreteDistribution=get_distribution(GC_fraction)),
        embedders)
    generated_sequences = tuple(
        synthetic.GenerateSequenceNTimes(embed_in_background,
                                         num_seqs).generateSequences())
    sequence_arr = np.array(
        [generated_seq.seq for generated_seq in generated_sequences])
    embedding_arr = [
        generated_seq.embeddings for generated_seq in generated_sequences
    ]
    return sequence_arr, embedding_arr
    def test_uniform_positions(self):
        pseudocount_prob = 0.001
        pwm_name = "CTCF_known1"
        num_sequences = 10000
        sequence_length = 50
        loaded_motifs = sn.LoadedEncodeMotifs(simdna.ENCODE_MOTIFS_PATH,
                                              pseudocountProb=pseudocount_prob)
        substring_generator = sn.PwmSamplerFromLoadedMotifs(
            loaded_motifs, pwm_name)
        position_generator = sn.UniformPositionGenerator()
        embedders = [
            sn.SubstringEmbedder(substring_generator, position_generator)
        ]
        embed_in_background = sn.EmbedInABackground(
            sn.ZeroOrderBackgroundGenerator(sequence_length,
                                            discreteDistribution={
                                                'A': 0.3,
                                                'C': 0.2,
                                                'G': 0.2,
                                                'T': 0.3
                                            }), embedders)
        generated_sequences = list(
            sn.GenerateSequenceNTimes(embed_in_background,
                                      num_sequences).generateSequences())

        motif_length = len(loaded_motifs.getPwm(pwm_name).getRows())
        start_pos_count = np.zeros(sequence_length - motif_length + 1)

        for seq in generated_sequences:
            assert len(seq.seq) == sequence_length
            embeddings = seq.embeddings
            for embedding in embeddings:
                assert (embedding.what.string ==
                        seq.seq[embedding.startPos:embedding.startPos +
                                len(embedding.what.string)])
                start_pos_count[embedding.startPos] += 1

        start_pos_count = start_pos_count / float(len(generated_sequences))
        np.testing.assert_almost_equal(start_pos_count,
                                       1.0 / len(start_pos_count), 2)
    def test_density_motif_embedding(self):
        random.seed(1234)
        np.random.seed(1234)
        min_counts = 2
        max_counts = 5
        pseudocount_prob = 0.001
        pwm_name = "CTCF_known1"
        num_sequences = 5000
        loaded_motifs = sn.LoadedEncodeMotifs(simdna.ENCODE_MOTIFS_PATH,
                                   pseudocountProb=pseudocount_prob)
        substring_generator = sn.PwmSamplerFromLoadedMotifs(
            loaded_motifs, pwm_name)
        position_generator = sn.UniformPositionGenerator()
        quantity_generator = sn.UniformIntegerGenerator(min_counts, max_counts)
        embedders = [
            sn.RepeatedEmbedder(
                sn.SubstringEmbedder(
                    sn.ReverseComplementWrapper(
                        substring_generator), position_generator),
                quantity_generator)]
        embed_in_background = sn.EmbedInABackground(
            sn.ZeroOrderBackgroundGenerator(
                500, discreteDistribution={'A':0.3,'C':0.2,
                                                  'G':0.2,'T':0.3}),
            embedders)
        generated_sequences = list(sn.GenerateSequenceNTimes(
            embed_in_background, num_sequences).generateSequences())
        assert len(generated_sequences) == num_sequences

        actual_pwm = np.array([[0.095290, 0.318729, 0.083242, 0.502738],
                         [0.182913, 0.158817, 0.453450, 0.204819],
                         [0.307777, 0.053669, 0.491785, 0.146769],
                         [0.061336, 0.876232, 0.023001, 0.039430],
                         [0.008762, 0.989047, 0.000000, 0.002191],
                         [0.814896, 0.014239, 0.071194, 0.099671],
                         [0.043812, 0.578313, 0.365827, 0.012048],
                         [0.117325, 0.474781, 0.052632, 0.355263],
                         [0.933114, 0.012061, 0.035088, 0.019737],
                         [0.005488, 0.000000, 0.991218, 0.003293],
                         [0.365532, 0.003293, 0.621295, 0.009879],
                         [0.059276, 0.013172, 0.553238, 0.374314],
                         [0.013187, 0.000000, 0.978022, 0.008791],
                         [0.061538, 0.008791, 0.851648, 0.078022],
                         [0.114411, 0.806381, 0.005501, 0.073707],
                         [0.409241, 0.014301, 0.557756, 0.018702],
                         [0.090308, 0.530837, 0.338106, 0.040749],
                         [0.128855, 0.354626, 0.080396, 0.436123],
                         [0.442731, 0.199339, 0.292952, 0.064978]])

        actual_pwm = actual_pwm*(1-pseudocount_prob) + pseudocount_prob/4
        np.testing.assert_almost_equal(np.sum(actual_pwm,axis=-1),1.0,6)
        np.testing.assert_almost_equal(
            actual_pwm,
            np.array(loaded_motifs.getPwm(pwm_name).getRows())) 
        letter_to_index = {'A':0, 'C':1, 'G':2, 'T':3}
        reconstructed_pwm_fwd = np.zeros_like(actual_pwm)
        reconstructed_pwm_rev = np.zeros_like(actual_pwm)
        quantity_distribution = defaultdict(lambda: 0) 
        total_fwd_embeddings = 0.0
        total_rev_embeddings = 0.0
        
        for seq in generated_sequences:
            embeddings = seq.embeddings
            quantity_distribution[len(embeddings)] += 1
            for embedding in embeddings:
                assert (embedding.what.string
                 ==seq.seq[embedding.startPos:
                       embedding.startPos+len(embedding.what.string)])
                if ('revComp' in embedding.what.getDescription()):
                    total_rev_embeddings += 1
                else:
                    total_fwd_embeddings += 1
                for char_idx, char in enumerate(embedding.what.string):
                    if ('revComp' in embedding.what.getDescription()):
                        arr = reconstructed_pwm_rev
                    else:
                        arr = reconstructed_pwm_fwd 
                    arr[char_idx][letter_to_index[char]] += 1

        total_embeddings = total_fwd_embeddings + total_rev_embeddings 
        np.testing.assert_almost_equal(
            total_fwd_embeddings/total_embeddings, 0.5, 2) 

        #normalize each column of reconstructed_pwm
        reconstructed_pwm_fwd = reconstructed_pwm_fwd/total_fwd_embeddings 
        reconstructed_pwm_rev = reconstructed_pwm_rev/total_rev_embeddings 
        np.testing.assert_almost_equal(actual_pwm, reconstructed_pwm_fwd, 2)
        np.testing.assert_almost_equal(actual_pwm,
                                       reconstructed_pwm_rev[::-1,::-1], 2)
       
        #test the quantities of motifs were sampled uniformly  
        for quantity in range(min_counts, max_counts+1):
            np.testing.assert_almost_equal(
             quantity_distribution[quantity]/float(num_sequences),
             1.0/(max_counts-min_counts+1),2)