本文整理汇总了Python中numpy.ma.masked_values方法的典型用法代码示例。如果您正苦于以下问题:Python ma.masked_values方法的具体用法?Python ma.masked_values怎么用?Python ma.masked_values使用的例子?那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类numpy.ma
的用法示例。
在下文中一共展示了ma.masked_values方法的11个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: generate_stimulus_xor
# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import masked_values [as 别名]
def generate_stimulus_xor(stim_times, gen_burst, n_inputs=2):
inp_states = np.random.randint(2, size=(n_inputs, np.size(stim_times)))
inp_spikes = []
for times in ma.masked_values(inp_states, 0) * stim_times:
# for each input (neuron): generate spikes according to state (=1) and stimulus time-grid
spikes = np.concatenate([t + gen_burst() for t in times.compressed()])
# round to simulation precision
spikes *= 10
spikes = spikes.round() + 1.0
spikes = spikes / 10.0
inp_spikes.append(spikes)
# astype(int) could be omitted, because False/True has the same semantics
targets = np.logical_xor(*inp_states).astype(int)
return inp_spikes, targets
示例2: test_missing_data_model
# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import masked_values [as 别名]
def test_missing_data_model(self):
# source pymc3/pymc3/tests/test_missing.py
data = ma.masked_values([1, 2, -1, 4, -1], value=-1)
model = pm.Model()
with model:
x = pm.Normal("x", 1, 1)
pm.Normal("y", x, 1, observed=data)
trace = pm.sample(100, chains=2)
# make sure that data is really missing
(y_missing,) = model.missing_values
assert y_missing.tag.test_value.shape == (2,)
inference_data = from_pymc3(trace=trace, model=model)
test_dict = {"posterior": ["x"], "observed_data": ["y"], "log_likelihood": ["y"]}
fails = check_multiple_attrs(test_dict, inference_data)
assert not fails
示例3: read
# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import masked_values [as 别名]
def read(self, output_tile, **kwargs):
"""
Read existing process output.
Parameters
----------
output_tile : ``BufferedTile``
must be member of output ``TilePyramid``
Returns
-------
process output : ``BufferedTile`` with appended data
"""
try:
return ma.masked_values(
read_raster_no_crs(
self.get_path(output_tile), indexes=(4 if self.old_band_num else 2)
),
0
)
except FileNotFoundError:
return self.empty(output_tile)
示例4: empty
# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import masked_values [as 别名]
def empty(self, process_tile):
"""
Return empty data.
Parameters
----------
process_tile : ``BufferedTile``
must be member of process ``TilePyramid``
Returns
-------
empty data : array or list
empty array with correct data type for raster data or empty list
for vector data
"""
return ma.masked_values(np.zeros(process_tile.shape), 0)
示例5: geoMean
# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import masked_values [as 别名]
def geoMean(array):
'''
Generate the geometric mean of a list or array,
removing all zero-values but retaining total length
'''
if isinstance(array, pandas.core.frame.DataFrame):
array = array.as_matrix()
else:
pass
non_zero = ma.masked_values(array,
0)
log_a = ma.log(non_zero)
geom_mean = ma.exp(log_a.mean())
return geom_mean
示例6: friedmanchisquare
# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import masked_values [as 别名]
def friedmanchisquare(*args):
"""Friedman Chi-Square is a non-parametric, one-way within-subjects ANOVA.
This function calculates the Friedman Chi-square test for repeated measures
and returns the result, along with the associated probability value.
Each input is considered a given group. Ideally, the number of treatments
among each group should be equal. If this is not the case, only the first
n treatments are taken into account, where n is the number of treatments
of the smallest group.
If a group has some missing values, the corresponding treatments are masked
in the other groups.
The test statistic is corrected for ties.
Masked values in one group are propagated to the other groups.
Returns: chi-square statistic, associated p-value
"""
data = argstoarray(*args).astype(float)
k = len(data)
if k < 3:
raise ValueError("Less than 3 groups (%i): " % k +
"the Friedman test is NOT appropriate.")
ranked = ma.masked_values(rankdata(data, axis=0), 0)
if ranked._mask is not nomask:
ranked = ma.mask_cols(ranked)
ranked = ranked.compressed().reshape(k,-1).view(ndarray)
else:
ranked = ranked._data
(k,n) = ranked.shape
# Ties correction
repeats = np.array([find_repeats(_) for _ in ranked.T], dtype=object)
ties = repeats[repeats.nonzero()].reshape(-1,2)[:,-1].astype(int)
tie_correction = 1 - (ties**3-ties).sum()/float(n*(k**3-k))
#
ssbg = np.sum((ranked.sum(-1) - n*(k+1)/2.)**2)
chisq = ssbg * 12./(n*k*(k+1)) * 1./tie_correction
return chisq, stats.chisqprob(chisq,k-1)
#-############################################################################-#
示例7: test_ma
# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import masked_values [as 别名]
def test_ma():
x = ma.array([1.0, 2, 3])
assert K(x) == k('1.0 2 3')
x = ma.masked_values([1.0, 0, 2], 0)
assert K(x) == k('1 0n 2')
s = ma.masked_values(0.0, 0)
assert K(s) == k('0n')
示例8: _prepare_masked
# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import masked_values [as 别名]
def _prepare_masked(data, masked, nodata, dtype):
if data.shape == data.mask.shape:
if masked:
return ma.masked_values(data.astype(dtype, copy=False), nodata, copy=False)
else:
return ma.filled(data.astype(dtype, copy=False), nodata)
else:
if masked:
return ma.masked_values(data.astype(dtype, copy=False), nodata, copy=False)
else:
return ma.filled(data.astype(dtype, copy=False), nodata)
示例9: friedmanchisquare
# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import masked_values [as 别名]
def friedmanchisquare(*args):
"""Friedman Chi-Square is a non-parametric, one-way within-subjects ANOVA.
This function calculates the Friedman Chi-square test for repeated measures
and returns the result, along with the associated probability value.
Each input is considered a given group. Ideally, the number of treatments
among each group should be equal. If this is not the case, only the first
n treatments are taken into account, where n is the number of treatments
of the smallest group.
If a group has some missing values, the corresponding treatments are masked
in the other groups.
The test statistic is corrected for ties.
Masked values in one group are propagated to the other groups.
Returns
-------
statistic : float
the test statistic.
pvalue : float
the associated p-value.
"""
data = argstoarray(*args).astype(float)
k = len(data)
if k < 3:
raise ValueError("Less than 3 groups (%i): " % k +
"the Friedman test is NOT appropriate.")
ranked = ma.masked_values(rankdata(data, axis=0), 0)
if ranked._mask is not nomask:
ranked = ma.mask_cols(ranked)
ranked = ranked.compressed().reshape(k,-1).view(ndarray)
else:
ranked = ranked._data
(k,n) = ranked.shape
# Ties correction
repeats = [find_repeats(row) for row in ranked.T]
ties = np.array([y for x, y in repeats if x.size > 0])
tie_correction = 1 - (ties**3-ties).sum()/float(n*(k**3-k))
ssbg = np.sum((ranked.sum(-1) - n*(k+1)/2.)**2)
chisq = ssbg * 12./(n*k*(k+1)) * 1./tie_correction
return FriedmanchisquareResult(chisq,
distributions.chi2.sf(chisq, k-1))
示例10: friedmanchisquare
# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import masked_values [as 别名]
def friedmanchisquare(*args):
"""Friedman Chi-Square is a non-parametric, one-way within-subjects ANOVA.
This function calculates the Friedman Chi-square test for repeated measures
and returns the result, along with the associated probability value.
Each input is considered a given group. Ideally, the number of treatments
among each group should be equal. If this is not the case, only the first
n treatments are taken into account, where n is the number of treatments
of the smallest group.
If a group has some missing values, the corresponding treatments are masked
in the other groups.
The test statistic is corrected for ties.
Masked values in one group are propagated to the other groups.
Returns
-------
statistic : float
the test statistic.
pvalue : float
the associated p-value.
"""
data = argstoarray(*args).astype(float)
k = len(data)
if k < 3:
raise ValueError("Less than 3 groups (%i): " % k +
"the Friedman test is NOT appropriate.")
ranked = ma.masked_values(rankdata(data, axis=0), 0)
if ranked._mask is not nomask:
ranked = ma.mask_cols(ranked)
ranked = ranked.compressed().reshape(k,-1).view(ndarray)
else:
ranked = ranked._data
(k,n) = ranked.shape
# Ties correction
repeats = np.array([find_repeats(_) for _ in ranked.T], dtype=object)
ties = repeats[repeats.nonzero()].reshape(-1,2)[:,-1].astype(int)
tie_correction = 1 - (ties**3-ties).sum()/float(n*(k**3-k))
ssbg = np.sum((ranked.sum(-1) - n*(k+1)/2.)**2)
chisq = ssbg * 12./(n*k*(k+1)) * 1./tie_correction
return FriedmanchisquareResult(chisq,
distributions.chi2.sf(chisq, k-1))
示例11: prepare_array
# 需要导入模块: from numpy import ma [as 别名]
# 或者: from numpy.ma import masked_values [as 别名]
def prepare_array(data, masked=True, nodata=0, dtype="int16"):
"""
Turn input data into a proper array for further usage.
Output array is always 3-dimensional with the given data type. If the output
is masked, the fill_value corresponds to the given nodata value and the
nodata value will be burned into the data array.
Parameters
----------
data : array or iterable
array (masked or normal) or iterable containing arrays
nodata : integer or float
nodata value (default: 0) used if input is not a masked array and
for output array
masked : bool
return a NumPy Array or a NumPy MaskedArray (default: True)
dtype : string
data type of output array (default: "int16")
Returns
-------
array : array
"""
# input is iterable
if isinstance(data, (list, tuple)):
return _prepare_iterable(data, masked, nodata, dtype)
# special case if a 2D single band is provided
elif isinstance(data, np.ndarray) and data.ndim == 2:
data = ma.expand_dims(data, axis=0)
# input is a masked array
if isinstance(data, ma.MaskedArray):
return _prepare_masked(data, masked, nodata, dtype)
# input is a NumPy array
elif isinstance(data, np.ndarray):
if masked:
return ma.masked_values(data.astype(dtype, copy=False), nodata, copy=False)
else:
return data.astype(dtype, copy=False)
else:
raise ValueError(
"Data must be array, masked array or iterable containing arrays. "
"Current data: %s (%s)" % (data, type(data))
)