Python numpy.where方法代码示例

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def show(mnist, targets, ret):
    target_ids = range(len(set(targets)))
    
    colors = ['r', 'g', 'b', 'c', 'm', 'y', 'k', 'violet', 'orange', 'purple']
    
    plt.figure(figsize=(12, 10))
    
    ax = plt.subplot(aspect='equal')
    for label in set(targets):
        idx = np.where(np.array(targets) == label)[0]
        plt.scatter(ret[idx, 0], ret[idx, 1], c=colors[label], label=label)
    
    for i in range(0, len(targets), 250):
        img = (mnist[i][0] * 0.3081 + 0.1307).numpy()[0]
        img = OffsetImage(img, cmap=plt.cm.gray_r, zoom=0.5) 
        ax.add_artist(AnnotationBbox(img, ret[i]))
    
    plt.legend()
    plt.show() 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def filter_roidb(roidb):
  """Remove roidb entries that have no usable RoIs."""

  def is_valid(entry):
    # Valid images have:
    #   (1) At least one foreground RoI OR
    #   (2) At least one background RoI
    overlaps = entry['max_overlaps']
    # find boxes with sufficient overlap
    fg_inds = np.where(overlaps >= cfg.TRAIN.FG_THRESH)[0]
    # Select background RoIs as those within [BG_THRESH_LO, BG_THRESH_HI)
    bg_inds = np.where((overlaps < cfg.TRAIN.BG_THRESH_HI) &
                       (overlaps >= cfg.TRAIN.BG_THRESH_LO))[0]
    # image is only valid if such boxes exist
    valid = len(fg_inds) > 0 or len(bg_inds) > 0
    return valid

  num = len(roidb)
  filtered_roidb = [entry for entry in roidb if is_valid(entry)]
  num_after = len(filtered_roidb)
  print('Filtered {} roidb entries: {} -> {}'.format(num - num_after,
                                                     num, num_after))
  return filtered_roidb 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def _evaluation(self, pop, eval_flag):
        # create network list
        net_lists = []
        active_index = np.where(eval_flag)[0]
        for i in active_index:
            net_lists.append(pop[i].active_net_list())

        # evaluation
        fp = self.eval_func(net_lists)
        for i, j in enumerate(active_index):
            pop[j].eval = fp[i]
        evaluations = np.zeros(len(pop))
        for i in range(len(pop)):
            evaluations[i] = pop[i].eval

        self.num_eval += len(net_lists)
        return evaluations 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def __iter__(self):
        indices = []
        for i, size in enumerate(self.group_sizes):
            if size == 0:
                continue
            indice = np.where(self.flag == i)[0]
            assert len(indice) == size
            np.random.shuffle(indice)
            num_extra = int(np.ceil(size / self.samples_per_gpu)
                            ) * self.samples_per_gpu - len(indice)
            indice = np.concatenate(
                [indice, np.random.choice(indice, num_extra)])
            indices.append(indice)
        indices = np.concatenate(indices)
        indices = [
            indices[i * self.samples_per_gpu:(i + 1) * self.samples_per_gpu]
            for i in np.random.permutation(
                range(len(indices) // self.samples_per_gpu))
        ]
        indices = np.concatenate(indices)
        indices = indices.astype(np.int64).tolist()
        assert len(indices) == self.num_samples
        return iter(indices) 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def _lsa_events_converter(events_file):
    """Make a model where each trial has its own regressor using least squares
    all (LSA)

    Parameters
    ----------
    events_file : str
        File that contains all events from the bold run

    Yields
    ------
    events : DataFrame
        A DataFrame in which each trial has its own trial_type
    """

    import pandas as pd
    events = pd.read_csv(events_file, sep='\t')
    events['original_trial_type'] = events['trial_type']
    for cond, cond_df in events.groupby('trial_type'):
        cond_idx = cond_df.index
        for i_trial, trial_idx in enumerate(cond_idx):
            trial_name = '{0}_{1:04d}'.format(cond, i_trial+1)
            events.loc[trial_idx, 'trial_type'] = trial_name
    return events 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def to_cortex(c):
    '''
    to_cortex(c) yields a Cortex object if the argument c can be coerced to one and otherwise raises
      an error.

    An object can be coerced to a Cortex object if:
      * it is a cortex object
      * it is a tuple (subject, h) where subject is a subject object and h is a subject hemisphere.
    '''
    if is_cortex(c): return c
    elif pimms.is_vector(c) and len(c) == 2:
        (s,h) = c
        if is_subject(s) and pimms.is_str(h):
            if h in s.hemis: return s.hemis[h]
            else: raise ValueError('to_cortex: hemi %s not found in given subject' % h)
    raise ValueError('Could not coerce argument to Cortex object')

####################################################################################################
# These functions deal with cortex_to_image and image_to_cortex interpolation: 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def to_potential(f):
    '''
    to_potential(f) yields f if f is a potential function; if f is not, but f can be converted to
      a potential function, that conversion is performed then the result is yielded.
    to_potential(Ellipsis) yields a potential function whose output is simply its input (i.e., the
      identity function).
    to_potential(None) is equivalent to to_potential(0).

    The following can be converted into potential functions:
      * Anything for which pimms.is_array(x, 'number') yields True (i.e., arrays of constants).
      * Any tuple (g, h) where g(x) yields a potential value and h(x) yields a jacobian matrix for
        the parameter vector x.
    '''
    if   is_potential(f): return f
    elif f is Ellipsis:   return identity
    elif pimms.is_array(f, 'number'): return const_potential(f)
    elif isinstance(f, tuple) and len(f) == 2: return PotentialLambda(f[0], f[1])
    else: raise ValueError('Could not convert object of type %s to potential function' % type(f)) 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def jacobian(self, params, into=None):
        params = flattest(params)
        n = len(params)
        ii = np.arange(n)
        (rs,cs,zs) = ([],[],[])
        for ((mn,mx), f) in self.pieces_with_default:
            if len(ii) == 0: break
            k = np.where((params >= mn) & (params <= mx))[0]
            if len(k) == 0: continue
            kk = ii[k]
            j = f.jacobian(params[k])
            if j.shape[0] == 1 and j.shape[1] > 1: j = repmat(j, j.shape[1], 1)
            (rj,cj,vj) = sps.find(j)
            rs.append(kk[rj])
            cs.append(kk[cj])
            zs.append(vj)
            ii = np.delete(ii, k)
            params = np.delete(params, k)
        (rs,cs,zs) = [np.concatenate(us) if len(us) > 0 else [] for us in (rs,cs,zs)]
        dz = sps.csr_matrix((zs, (rs,cs)), shape=(n,n))
        return safe_into(into, dz) 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def signed_face_areas(faces, axis=1):
    '''
    signed_face_areas(faces) yields a potential function f(x) that calculates the signed area of
      each face represented by the simplices matrix faces.

    If faces is None, then the parameters must arrive in the form of a flattened (n x 3 x 2) matrix
    where n is the number of triangles. Otherwise, the faces matrix must be either (n x 3) or (n x 3
    x s); if the former, each row must list the vertex indices for the faces where the vertex matrix
    is presumed to be shaped (V x 2). Alternately, faces may be a full (n x 3 x 2) simplex array of
    the indices into the parameters.

    The optional argument axis (default: 1) may be set to 0 if the faces argument is a matrix but
    the coordinate matrix will be (2 x V) instead of (V x 2).
    '''
    faces = np.asarray(faces)
    if len(faces.shape) == 2:
        if faces.shape[1] != 3: faces = faces.T
        n = 2 * (np.max(faces) + 1)
        if axis == 0: tmp = np.reshape(np.arange(n), (2,-1)).T
        else:         tmp = np.reshape(np.arange(n), (-1,2))
        faces = np.reshape(tmp[faces.flat], (-1,3,2))
    faces = faces.flatten()
    return compose(TriangleSignedArea2DPotential(), part(Ellipsis, faces)) 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def face_areas(faces, axis=1):
    '''
    face_areas(faces) yields a potential function f(x) that calculates the unsigned area of each
      faces represented by the simplices matrix faces.

    If faces is None, then the parameters must arrive in the form of a flattened (n x 3 x 2) matrix
    where n is the number of triangles. Otherwise, the faces matrix must be either (n x 3) or (n x 3
    x s); if the former, each row must list the vertex indices for the faces where the vertex matrix
    is presumed to be shaped (V x 2). Alternately, faces may be a full (n x 3 x 2) simplex array of
    the indices into the parameters.

    The optional argument axis (default: 1) may be set to 0 if the faces argument is a matrix but
    the coordinate matrix will be (2 x V) instead of (V x 2).
    '''
    faces = np.asarray(faces)
    if len(faces.shape) == 2:
        if faces.shape[1] != 3: faces = faces.T
        n = 2 * (np.max(faces) + 1)
        if axis == 0: tmp = np.reshape(np.arange(n), (2,-1)).T
        else:         tmp = np.reshape(np.arange(n), (-1,2))
        faces = np.reshape(tmp[faces.flat], (-1,3,2))
    faces = faces.flatten()
    return compose(TriangleArea2DPotential(), part(Ellipsis, faces)) 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def dataframe_select(df, *cols, **filters):
    '''
    dataframe_select(df, k1=v1, k2=v2...) yields df after selecting all the columns in which the
      given keys (k1, k2, etc.) have been selected such that the associated columns in the dataframe
      contain only the rows whose cells match the given values.
    dataframe_select(df, col1, col2...) selects the given columns.
    dataframe_select(df, col1, col2..., k1=v1, k2=v2...) selects both.
    
    If a value is a tuple/list of 2 elements, then it is considered a range where cells must fall
    between the values. If value is a tuple/list of more than 2 elements or is a set of any length
    then it is a list of values, any one of which can match the cell.
    '''
    ii = np.ones(len(df), dtype='bool')
    for (k,v) in six.iteritems(filters):
        vals = df[k].values
        if   pimms.is_set(v):                    jj = np.isin(vals, list(v))
        elif pimms.is_vector(v) and len(v) == 2: jj = (v[0] <= vals) & (vals < v[1])
        elif pimms.is_vector(v):                 jj = np.isin(vals, list(v))
        else:                                    jj = (vals == v)
        ii = np.logical_and(ii, jj)
    if len(ii) != np.sum(ii): df = df.loc[ii]
    if len(cols) > 0: df = df[list(cols)]
    return df 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def arccosine(x, null=(-np.inf, np.inf)):
    '''
    arccosine(x) is equivalent to acos(x) except that it also works on sparse arrays.

    The optional argument null (default, (-numpy.inf, numpy.inf)) may be specified to indicate what
    value(s) should be assigned when x < -1 or x > 1. If only one number is given, then it is used
    for both values; otherwise the first value corresponds to <-1 and the second to >1.  If null is
    None, then an error is raised when invalid values are encountered.
    '''
    if sps.issparse(x): x = x.toarray()
    else:               x = np.asarray(x)
    try:    (nln,nlp) = null
    except Exception: (nln,nlp) = (null,null)
    ii = None if nln is None else np.where(x < -1)
    jj = None if nlp is None else np.where(x > 1)
    if ii: x[ii] = 0
    if jj: x[jj] = 0
    x = np.arccos(x)
    if ii: x[ii] = nln
    if jj: x[jj] = nlp
    return x 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def splrep(coordinates, t, order, weights, smoothing, periodic):
        from scipy import interpolate
        (x,y) = coordinates
        # we need to skip anything where t[i] and t[i+1] are too close
        wh = np.where(np.isclose(np.diff(t), 0))[0]
        if len(wh) > 0:
            (t,x,y) = [np.array(u) for u in (t,x,y)]
            ii = np.arange(len(t))
            for i in reversed(wh):
                ii[i+1:-1] = ii[i+2:]
                for u in (t,x,y):
                    u[i] = np.mean(u[i:i+2])
            ii = ii[:-len(wh)]
            (t,x,y) = [u[ii] for u in (t,x,y)]
        xtck = interpolate.splrep(t, x, k=order, s=smoothing, w=weights, per=periodic)
        ytck = interpolate.splrep(t, y, k=order, s=smoothing, w=weights, per=periodic)
        return tuple([tuple([pimms.imm_array(u) for u in tck])
                      for tck in (xtck,ytck)]) 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def collect(self, index, dataDict, check=True):
        """
        Collect atom given its index.

        :Parameters:
            #. index (int): The atom index to collect.
            #. dataDict (dict): The atom data dict to collect.
            #. check (boolean):  Whether to check dataDict keys before
               collecting. If set to False, user promises that collected
               data is a dictionary and contains the needed keys.
        """
        assert not self.is_collected(index), LOGGER.error("attempting to collect and already collected atom of index '%i'"%index)
        # add data
        if check:
            assert isinstance(dataDict, dict), LOGGER.error("dataDict must be a dictionary of data where keys are dataKeys")
            assert tuple(sorted(dataDict)) == self.__dataKeys, LOGGER.error("dataDict keys don't match promised dataKeys")
        self.__collectedData[index] = dataDict
        # set indexes sorted array
        idx = np.searchsorted(a=self.__indexesSortedArray, v=index, side='left')
        self.__indexesSortedArray = np.insert(self.__indexesSortedArray, idx, index)
        # set state
        self.__state = str(uuid.uuid1()) 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import where [as 别名]
def __on_scan_data(self, event):
        levels = numpy.log10(event['l'])
        levels *= 10

        noise = numpy.percentile(levels,
                                 self._dynP)

        for monitor in self._monitors:
            freq = monitor.get_frequency()
            if monitor.get_enabled():
                monitor.set_noise(noise)
                index = numpy.where(freq == event['f'])[0]
                signal = monitor.set_level(levels[index][0],
                                           event['timestamp'],
                                           self._location)

                if signal is not None:
                    signals = 'Signals: {}\r'.format(self.__count_signals() -
                                                     self._signalCount)
                    self.__std_out(signals, False)
                    if signal.end is not None:
                        recording = format_recording(freq, signal)
                        if self._pushUri is not None:
                            self._push.send(self._pushUri,
                                            recording)
                        if self._server is not None:
                            self._server.send(recording)
                        if self._json:
                            sys.stdout.write(recording + '\n')