# Sample¶

class Sample(*args)

Sample of real vectors.

Available constructors:

Sample(size, dim)

Sample(size, point)

Sample(other, first, last)

Parameters
sizeint, , optional

The sample size. Default creates an empty sample with dimension 1.

dimensionint, , optional

The real vectors dimension. Default creates an empty sample with dimension 1.

pointPoint or flat (1d) array, list or tuple of floats, optional

The point that will be repeated along the sample. Default creates a sample filled with zeros (null vectors).

otherSample

The sample contains points to copy.

firstint,

The index of the first point to copy.

lastint, , optional

The index after the last point to copy.

Examples

Create a Sample

>>> import openturns as ot
>>> import numpy as np
>>> sample = ot.Sample(3, 2)
>>> print(sample)
0 : [ 0 0 ]
1 : [ 0 0 ]
2 : [ 0 0 ]
>>> sample = ot.Sample(3, [1.0, 2.0])
>>> print(sample)
0 : [ 1 2 ]
1 : [ 1 2 ]
2 : [ 1 2 ]


Create a Sample from a (2d) array, list or tuple

>>> import numpy as np
>>> sample = ot.Sample(np.array([(1.0, 2.0), (3.0, 4.0), (5.0, 6.0)]))


and back

>>> z = np.array(sample)


Eventually samples may also be generated from probability distributions or experiments

>>> random_sample = ot.Normal(2).getSample(10)
>>> experiment = ot.LHSExperiment(ot.Normal(2), 10).generate()


Translation: addition or subtraction of a (compatible) sample or a point, or a scalar which is promoted into a point of compatible dimension with equal components

>>> print(sample + sample)
0 : [  2  4 ]
1 : [  6  8 ]
2 : [ 10 12 ]
>>> print(sample - sample)
0 : [ 0 0 ]
1 : [ 0 0 ]
2 : [ 0 0 ]
>>> print(sample - sample[0])
0 : [ 0 0 ]
1 : [ 2 2 ]
2 : [ 4 4 ]
>>> print(sample - sample[0, 0])
0 : [ 0 1 ]
1 : [ 2 3 ]
2 : [ 4 5 ]


Methods

 ImportFromCSVFile(\*args) Static method for building a sample from a CSV file. ImportFromTextFile(\*args) Static method for building a sample from a text file. add(self, \*args) Append a vector (in-place). asPoint(self) Accessor to the internal linear storage for 1D sample. clear(self) Erase all values. computeCenteredMoment(self, k) Estimate componentwise centered moments. Estimate the covariance matrix. computeEmpiricalCDF(self, point[, tail]) Estimate the empirical cumulative distribution function (ECDF). Estimate the Kendall coefficients matrix. Estimate the componentwise kurtosis (4th order centered normalized moment). (ditch me?) computeMean(self) Estimate the mean vector. computeMedian(self) Estimate the componentwise medians (50%-quantiles). Estimate the Pearson correlation matrix. computeQuantile(self, \*args) Estimate the quantile of the joint distribution underlying the sample. computeQuantilePerComponent(self, \*args) Estimate the componentwise quantiles. computeRange(self) Compute the range per component. computeRawMoment(self, k) Compute the raw (non-centered) moment per component. Estimate the componentwise skewness (3rd order centered normalized moment). Estimate the Spearman correlation matrix. Compute the Cholesky factor of the covariance matrix. Estimate the componentwise standard deviations. Estimate the componentwise variances. erase(self, \*args) Erase point(s) at or between index(es) (in-place). exportToCSVFile(self, \*args) Dump the sample to a CSV file. find(self, point) Get the position of a point in the sample. getClassName(self) Accessor to the object’s name. getDescription(self) Accessor to the componentwise description. getDimension(self) Accessor to the sample’s dimension. getId(self) Accessor to the object’s id. Accessor to the underlying implementation. getMarginal(self, \*args) Accessor to sample marginal(s) (column(s)). getMax(self) Accessor to the componentwise maximum values. getMin(self) Accessor to the componentwise minimum values. getName(self) Accessor to the object’s name. getSize(self) Accessor to the sample size. rank(self, \*args) Compute the sample (componentwise) ranks. select(self, indices) Select points in a sample. setDescription(self, description) Accessor to the componentwise description. setName(self, name) Accessor to the object’s name. sort(self, \*args) Sort the sample. sortAccordingToAComponent(self, index) Sort the sample according to the given component. sortAccordingToAComponentInPlace(self, index) Sort the sample in place according to the given component. sortInPlace(self) Sort the sample in place. sortUnique(self) Sort the sample and remove duplicate points. Sort the sample in place and remove duplicate points. split(self, index) Trunk the sample. stack(self, sample) Stack (horizontally) the given sample to the current one (in-place).
__init__(self, \*args)

Initialize self. See help(type(self)) for accurate signature.

static ImportFromCSVFile(\*args)

Static method for building a sample from a CSV file.

Parameters
file_namestr

Path to CSV file.

separatorstr

Separating string. Default uses csv-file-separator from the ResourceMap.

Returns
sampleSample

Sample loaded from the CSV file.

Notes

The file may or may not contain a header line (columns spanned with strings delimited with quotes). If it does contain such a header line, it will be used for setting the sample description using setDescription().

Examples

>>> import openturns as ot


Let’s first create a sample CSV file

>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> sample.exportToCSVFile('sample.csv')


>>> loaded_sample = ot.Sample.ImportFromCSVFile('sample.csv')

static ImportFromTextFile(\*args)

Static method for building a sample from a text file.

Parameters
file_namestr

Path to text file.

separatorstr

Separating string. Default uses a blank space.

skipped_linesint

Number of lines skipped. Default is 0.

Returns
sampleSample

Sample loaded from the text file.

Notes

The file may or may not contain a header line (columns spanned with strings delimited with quotes). If it does contain such a header line, it will be used for setting the sample description using setDescription(). It can also contain some comments, if a line starts with one of the characters contained in Sample-CommentsMarker from the ResourceMap.

Examples

>>> import openturns as ot


Let’s first create a sample text file

>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> sample.exportToCSVFile('sample.txt', ' ')


>>> loaded_sample = ot.Sample.ImportFromTextFile('sample.txt')

add(self, \*args)

Append a vector (in-place).

Parameters
pointsequence of float

The point to append.

Examples

>>> import openturns as ot
>>> sample = ot.Sample(3, 2)
>>> print(sample)
0 : [ 0 0 ]
1 : [ 0 0 ]
2 : [ 0 0 ]
3 : [ 1 2 ]

asPoint(self)

Accessor to the internal linear storage for 1D sample.

Returns
valuesPoint

Flat internal representation of the sample.

Notes

Available only for 1D sample.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal().getSample(5)
>>> print(sample)
[ X0        ]
0 : [  0.608202 ]
1 : [ -1.26617  ]
2 : [ -0.438266 ]
3 : [  1.20548  ]
4 : [ -2.18139  ]
>>> print(sample.asPoint())
[0.608202,-1.26617,-0.438266,1.20548,-2.18139]

clear(self)

Erase all values.

computeCenteredMoment(self, k)

Estimate componentwise centered moments.

Parameters
kint

The centered moment’s order.

Returns
mPoint

Componentwise centered moment of order estimated from the sample.

Notes

The centered moment of order is estimated as follows:

where is the estimator of the mean.

These estimators are the natural (possibly biased) estimators. For unbiased estimators use the other dedicated methods such as computeVariance() for the variance.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeCenteredMoment(2))
[0.915126,0.873119]

computeCovariance(self)

Estimate the covariance matrix.

Returns
covarianceCovarianceMatrix

Covariance matrix estimated from the sample.

Notes

The covariance matrix is estimated as follows:

where denotes the estimate of the mean.

This is an unbiased estimator.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeCovariance())
[[ 0.946682  0.0182104 ]
[ 0.0182104 0.903226  ]]

computeEmpiricalCDF(self, point, tail=False)

Estimate the empirical cumulative distribution function (ECDF).

Parameters
xsequence of float

CDF input.

survivalbool, optional

A flag telling whether this should estimate the empirical cumulative distribution function or the empirical survival function. Default is False and estimates the CDF.

Returns
pfloat,

Empirical CDF or SF value at point x.

Notes

The empirical cumulative distribution function (CDF) is estimated as follows:

The empirical survival function (SF) is estimated in a similar way:

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeEmpiricalCDF(sample[0]))
0.1

computeKendallTau(self)

Estimate the Kendall coefficients matrix.

Returns
tauCorrelationMatrix

Kendall coefficients matrix estimated from the sample.

Notes

This uses an external implementation provided under the Boost Software License by David Simcha based on the paper by [knight1966]. It actually switches between two implementations depending on the sample size:

• The most basic implementation performing in is used when the sample size is less than SampleImplementation-SmallKendallTau from the ResourceMap.

• The other more complex implementation performing in is used for larger samples.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeKendallTau())
[[ 1          0.00689655 ]
[ 0.00689655 1          ]]

computeKurtosis(self)

Estimate the componentwise kurtosis (4th order centered normalized moment).

Returns
kurtosisPoint

Componentwise kurtosis estimated from the sample.

Notes

The componentwise kurtosis are estimated as follows:

where is the estimate of the mean.

This estimator is unbiased.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeKurtosis())
[3.27647,2.40275]

computeLinearCorrelation(self)

(ditch me?)

computeMean(self)

Estimate the mean vector.

Returns
meanPoint

Mean vector estimated from the sample.

Notes

The mean is estimated as follows:

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeMean())
[-0.0512622,0.136653]

computeMedian(self)

Estimate the componentwise medians (50%-quantiles).

Returns
medianPoint

Median vector estimated from the sample.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeMedian())
[0.221141,0.108703]

computePearsonCorrelation(self)

Estimate the Pearson correlation matrix.

Returns
rhoCorrelationMatrix

Pearson correlation matrix estimated from the sample.

Notes

The Pearson correlation matrix is estimated as follows:

where denotes the estimate of the covariance.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computePearsonCorrelation())
[[ 1         0.0196933 ]
[ 0.0196933 1         ]]

computeQuantile(self, \*args)

Estimate the quantile of the joint distribution underlying the sample.

Parameters
pfloat, , or sequence of float

Input probability level.

Returns
quantile

Quantile of the joint distribution at probability level , estimated from the sample.

Raises
NotImplementedYetErrorIf the dimension is greater than 1.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(1).getSample(30)
>>> print(sample.computeQuantile(.2))
[-0.947394]

computeQuantilePerComponent(self, \*args)

Estimate the componentwise quantiles.

Parameters
pfloat, , or sequence of float

Input probability level.

Returns
quantile

Componentwise quantile at probability level , estimated from the sample.

Notes

The present implementation interpolates the quantile between the two adjacent empirical quantiles ( and ):

where .

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeQuantilePerComponent(0.2))
[-0.696412,-0.767092]

computeRange(self)

Compute the range per component.

Returns
rangePoint

Componentwise ranges estimated from the sample.

Notes

The statistical range is defined as the deviation between the maximal and the minimal value of the sample.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeRange())
[4.02827,3.49949]

computeRawMoment(self, k)

Compute the raw (non-centered) moment per component.

Parameters
kint,

Componentwise moment’s order.

Returns
momentsPoint

Componentwise moments estimated from the sample.

Notes

The (raw) moment of order is estimated as follows:

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeRawMoment(2))
[0.917754,0.891793]

computeSkewness(self)

Estimate the componentwise skewness (3rd order centered normalized moment).

Returns
skewnessPoint

Componentwise skewness estimated from the sample.

Notes

The componentwise skewnesses are estimated as follows:

where is the estimate of the mean.

This is an unbiased estimator.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeSkewness())
[-0.69393,0.231931]

computeSpearmanCorrelation(self)

Estimate the Spearman correlation matrix.

Returns
rhoCorrelationMatrix

Spearman correlation matrix estimated from the sample.

Notes

The Spearman correlation matrix is estimated as the Pearson correlation matrix of the ranks sample (i.e. using self.rank().computePearsonCorrelation()).

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeSpearmanCorrelation())
[[  1          -0.00556174 ]
[ -0.00556174  1          ]]

computeStandardDeviation(self)

Compute the Cholesky factor of the covariance matrix.

Estimated from the sample.

Returns
LTriangularMatrix

Lower (left) Cholesky factor of the covariance matrix estimated from the sample.

Raises
RuntimeErrorIf the estimated covariance matrix is not positive definite. In

this case, you might want to estimate the covariance and manually shrink negative eigenvalues.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeStandardDeviation())
[[ 0.972976  0         ]
[ 0.0187161 0.950198  ]]

computeStandardDeviationPerComponent(self)

Estimate the componentwise standard deviations.

Returns
standard_deviationsPoint

Componentwise standard deviation estimated from the sample.

Notes

The componentwise standard deviations are estimated as the square root of the componentwise variances.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeStandardDeviationPerComponent())
[0.972976,0.950382]

computeVariance(self)

Estimate the componentwise variances.

Returns
variancesPoint

Componentwise variances estimated from the sample.

Notes

The componentwise variances are estimated as follows:

where is the estimate of the mean.

This estimator is unbiased.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.computeVariance())
[0.946682,0.903226]

erase(self, \*args)

Erase point(s) at or between index(es) (in-place).

Parameters
fint,

The index of the first point to erase.

lint, , optional

The index after the last point to erase. Default uses l = f + 1 and only removes sample[f].

Returns
——-
erased_sampleSample

Erased sample [sample[:i_start:], sample[i_stop::]].

Examples

>>> import openturns as ot
>>> sample = ot.Sample([[i] for i in range(5)])
>>> print(sample)
0 : [ 0 ]
1 : [ 1 ]
2 : [ 2 ]
3 : [ 3 ]
4 : [ 4 ]
>>> sample.erase(1, 3)
>>> print(sample)
0 : [ 0 ]
1 : [ 3 ]
2 : [ 4 ]

exportToCSVFile(self, \*args)

Dump the sample to a CSV file.

Parameters
file_namestr

Path to CSV file.

separatorstr

Separating string. Default uses csv-file-separator from the ResourceMap.

Notes

This will create a header line with componentwise descriptions (obtained from getDescription()) between quotes as column names.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> sample.exportToCSVFile('sample.csv', '; ')

find(self, point)

Get the position of a point in the sample.

Parameters
pointsequence of float

The wanted point.

Returns
indexint,

Returns if the point does not belong to the sample.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(30)
>>> print(sample.find(sample[10]))
10
>>> print(sample.find([0.0, 0.0]))
30

getClassName(self)

Accessor to the object’s name.

Returns
class_namestr

The object class name (object.__class__.__name__).

getDescription(self)

Accessor to the componentwise description.

Returns
descriptionDescription

Description of the sample’s components.

getDimension(self)

Accessor to the sample’s dimension.

Returns
nint

The number of components of the points in the sample.

getId(self)

Accessor to the object’s id.

Returns
idint

Internal unique identifier.

getImplementation(self)

Accessor to the underlying implementation.

Returns
implImplementation

The implementation class.

getMarginal(self, \*args)

Accessor to sample marginal(s) (column(s)).

Parameters
indicesint, sequence of int, or sequence of str

The identifiers of the wanted marginal(s). When the description contains duplicate labels, the first marginal is picked up.

Returns
sampleSample

A subsample of the present sample with the requested marginal(s).

Notes

The Sample also implements slicing in its __getitem__ method.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(10).getSample(3)
>>> print(sample.getMarginal([1, 4]))
[ X1        X4        ]
0 : [ -1.26617  -2.18139  ]
1 : [  0.261018 -1.31178  ]
2 : [  0.445785  0.473617 ]

getMax(self)

Accessor to the componentwise maximum values.

Returns
maximum_valuesPoint

Componentwise maximum values.

getMin(self)

Accessor to the componentwise minimum values.

Returns
minimum_valuesPoint

Componentwise minimum values.

getName(self)

Accessor to the object’s name.

Returns
namestr

The name of the object.

getSize(self)

Accessor to the sample size.

Returns
mint

The number points in the sample.

rank(self, \*args)

Compute the sample (componentwise) ranks.

Parameters
marginal_indexint, , optional

The component whose ranks are wanted. Default computes the ranks of all the components.

Returns
ranksSample

The requested ranks.

Notes

The ranks of a 1d sample is a list of indices that sorts the points in the ascending order. Ties (equal points) are averaged.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(3)
>>> print(sample)
[ X0        X1        ]
0 : [  0.608202 -1.26617  ]
1 : [ -0.438266  1.20548  ]
2 : [ -2.18139   0.350042 ]
>>> print(sample.rank())
[ X0 X1 ]
0 : [ 2  0  ]
1 : [ 1  2  ]
2 : [ 0  1  ]

select(self, indices)

Select points in a sample.

It selects the points at given locations and returns them as a new sample.

Parameters
indicessequence of int,

The selected indices.

Returns
selected_sampleSample

The selected points as a sample.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(3)
>>> print(sample)
[ X0        X1        ]
0 : [  0.608202 -1.26617  ]
1 : [ -0.438266  1.20548  ]
2 : [ -2.18139   0.350042 ]
>>> selected_sample = sample.select([1, 0, 1])
>>> print(selected_sample)
[ X0        X1        ]
0 : [ -0.438266  1.20548  ]
1 : [  0.608202 -1.26617  ]
2 : [ -0.438266  1.20548  ]

setDescription(self, description)

Accessor to the componentwise description.

Parameters
descriptionsequence of str

Description of the sample’s components.

setName(self, name)

Accessor to the object’s name.

Parameters
namestr

The name of the object.

sort(self, \*args)

Sort the sample.

Parameters
marginal_indexint, , optional

The component to sort. Default sorts the whole sample.

Returns
sorted_sampleSample

The requested sorted sample.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(3)
>>> print(sample)
[ X0        X1        ]
0 : [  0.608202 -1.26617  ]
1 : [ -0.438266  1.20548  ]
2 : [ -2.18139   0.350042 ]
>>> print(sample.sort())
[ X0        X1        ]
0 : [ -2.18139   0.350042 ]
1 : [ -0.438266  1.20548  ]
2 : [  0.608202 -1.26617  ]

sortAccordingToAComponent(self, index)

Sort the sample according to the given component.

Parameters
marginal_indexint,

The component to use for sorting the sample.

Returns
sorted_sampleSample

The sample sorted according to the given component.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(3)
>>> print(sample)
[ X0        X1        ]
0 : [  0.608202 -1.26617  ]
1 : [ -0.438266  1.20548  ]
2 : [ -2.18139   0.350042 ]
>>> print(sample.sortAccordingToAComponent(0))
[ X0        X1        ]
0 : [ -2.18139   0.350042 ]
1 : [ -0.438266  1.20548  ]
2 : [  0.608202 -1.26617  ]

sortAccordingToAComponentInPlace(self, index)

Sort the sample in place according to the given component.

Parameters
marginal_indexint,

The component to use for sorting the sample.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(3)
>>> print(sample)
[ X0        X1        ]
0 : [  0.608202 -1.26617  ]
1 : [ -0.438266  1.20548  ]
2 : [ -2.18139   0.350042 ]
>>> sample.sortAccordingToAComponentInPlace(0)
>>> print(sample)
[ X0        X1        ]
0 : [ -2.18139   0.350042 ]
1 : [ -0.438266  1.20548  ]
2 : [  0.608202 -1.26617  ]

sortInPlace(self)

Sort the sample in place.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(3)
>>> print(sample)
[ X0        X1        ]
0 : [  0.608202 -1.26617  ]
1 : [ -0.438266  1.20548  ]
2 : [ -2.18139   0.350042 ]
>>> sample.sortInPlace()
>>> print(sample)
[ X0        X1        ]
0 : [ -2.18139   0.350042 ]
1 : [ -0.438266  1.20548  ]
2 : [  0.608202 -1.26617  ]

sortUnique(self)

Sort the sample and remove duplicate points.

Returns
unique_sampleSample

The requested sorted sample with duplicate points removed.

Examples

>>> import openturns as ot
>>> sample = ot.Sample([[3, 0, 3], [1, 1, 0], [0, 2, 2], [1, 1, 0]])
>>> print(sample)
0 : [ 3 0 3 ]
1 : [ 1 1 0 ]
2 : [ 0 2 2 ]
3 : [ 1 1 0 ]
>>> print(sample.sortUnique())
0 : [ 0 2 2 ]
1 : [ 1 1 0 ]
2 : [ 3 0 3 ]

sortUniqueInPlace(self)

Sort the sample in place and remove duplicate points.

Examples

>>> import openturns as ot
>>> sample = ot.Sample([[3, 0, 3], [1, 1, 0], [0, 2, 2], [1, 1, 0]])
>>> print(sample)
0 : [ 3 0 3 ]
1 : [ 1 1 0 ]
2 : [ 0 2 2 ]
3 : [ 1 1 0 ]
>>> sample.sortUniqueInPlace()
>>> print(sample)
0 : [ 0 2 2 ]
1 : [ 1 1 0 ]
2 : [ 3 0 3 ]

split(self, index)

Trunk the sample.

It splits the sample before the index passed as argument and returns the remainder as new sample.

Parameters
indexint,

The truncation index.

Returns
remainder_sampleSample

The remainder sample (everyting that comes after the truncation index).

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(3)
>>> print(sample)
[ X0        X1        ]
0 : [  0.608202 -1.26617  ]
1 : [ -0.438266  1.20548  ]
2 : [ -2.18139   0.350042 ]
>>> remainder_sample = sample.split(1)
>>> print(sample)
[ X0        X1        ]
0 : [  0.608202 -1.26617  ]
>>> print(remainder_sample)
[ X0        X1        ]
0 : [ -0.438266  1.20548  ]
1 : [ -2.18139   0.350042 ]

stack(self, sample)

Stack (horizontally) the given sample to the current one (in-place).

Parameters
sampleSample

Sample to stack with compatible size.

Examples

>>> import openturns as ot
>>> ot.RandomGenerator.SetSeed(0)
>>> sample = ot.Normal(2).getSample(3)
>>> print(sample)
[ X0        X1        ]
0 : [  0.608202 -1.26617  ]
1 : [ -0.438266  1.20548  ]
2 : [ -2.18139   0.350042 ]
>>> another_sample = ot.Normal(2).getSample(3)
>>> print(another_sample)
[ X0        X1        ]
0 : [ -0.355007  1.43725  ]
1 : [  0.810668  0.793156 ]
2 : [ -0.470526  0.261018 ]
>>> sample.stack(another_sample)
>>> print(sample)
[ X0        X1        X0        X1        ]
0 : [  0.608202 -1.26617  -0.355007  1.43725  ]
1 : [ -0.438266  1.20548   0.810668  0.793156 ]
2 : [ -2.18139   0.350042 -0.470526  0.261018 ]