larray.LArray

class larray.LArray(data, axes=None, title='')[source]

A LArray object represents a multidimensional, homogeneous array of fixed-size items with labeled axes.

The function aslarray() can be used to convert a NumPy array or Pandas DataFrame into a LArray.

Parameters:

data : scalar, tuple, list or NumPy ndarray

Input data.

axes : collection (tuple, list or AxisCollection) of axes (int, str or Axis), optional

Axes.

title : str, optional

Title of array.

See also

sequence
Create a LArray by sequentially applying modifications to the array along axis.
ndrange
Create a LArray with increasing elements.
zeros
Create a LArray, each element of which is zero.
ones
Create a LArray, each element of which is 1.
full
Create a LArray filled with a given value.
empty
Create a LArray, but leave its allocated memory unchanged (i.e., it contains “garbage”).

Examples

>>> age = Axis([10, 11, 12], 'age')
>>> sex = Axis('sex=M,F')
>>> time = Axis([2007, 2008, 2009], 'time')
>>> axes = [age, sex, time]
>>> data = np.zeros((len(axes), len(sex), len(time)))
>>> LArray(data, axes)
age  sex\time  2007  2008  2009
 10         M   0.0   0.0   0.0
 10         F   0.0   0.0   0.0
 11         M   0.0   0.0   0.0
 11         F   0.0   0.0   0.0
 12         M   0.0   0.0   0.0
 12         F   0.0   0.0   0.0
>>> full(axes, 10.0)
age  sex\time  2007  2008  2009
 10         M  10.0  10.0  10.0
 10         F  10.0  10.0  10.0
 11         M  10.0  10.0  10.0
 11         F  10.0  10.0  10.0
 12         M  10.0  10.0  10.0
 12         F  10.0  10.0  10.0
>>> arr = empty(axes)
>>> arr['F'] = 1.0
>>> arr['M'] = -1.0
>>> arr
age  sex\time  2007  2008  2009
 10         M  -1.0  -1.0  -1.0
 10         F   1.0   1.0   1.0
 11         M  -1.0  -1.0  -1.0
 11         F   1.0   1.0   1.0
 12         M  -1.0  -1.0  -1.0
 12         F   1.0   1.0   1.0
>>> bysex = sequence(sex, initial=-1, inc=2)
>>> bysex
sex   M  F
     -1  1
>>> sequence(age, initial=10, inc=bysex)
sex\age  10  11  12
      M  10   9   8
      F  10  11  12

Attributes

data (NumPy ndarray) Data.
axes (AxisCollection) Axes.
title (str) Title.
__init__(data, axes=None, title='')[source]

Methods

__init__(data[, axes, title])
align(other[, join, fill_value, axes]) Align two arrays on their axes with the specified join method.
all(*axes_and_groups[, out, skipna, keepaxes]) Test whether all selected elements evaluate to True.
all_by(*axes_and_groups[, out, skipna, keepaxes]) Test whether all selected elements evaluate to True.
any(*axes_and_groups[, out, skipna, keepaxes]) Test whether any selected elements evaluate to True.
any_by(*axes_and_groups[, out, skipna, keepaxes]) Test whether any selected elements evaluate to True.
append(axis, value[, label]) Adds an array to self along an axis.
argmax(*args, **kwargs)
argmin(*args, **kwargs)
argsort(*args, **kwargs)
as_table([maxlines, edgeitems, light]) Generator.
astype(dtype[, order, casting, subok, copy]) Copy of the array, cast to a specified type.
broadcast_with(target) Returns an array that is (NumPy) broadcastable with target.
clip(a_min, a_max[, out]) Clip (limit) the values in an array.
combine_axes([axes, sep, wildcard]) Combine several axes into one.
compact() Detects and removes “useless” axes (ie axes for which values are constant over the whole axis)
copy() Returns a copy of the array.
cumprod([axis]) Returns the cumulative product of array elements.
cumsum([axis]) Returns the cumulative sum of array elements along an axis.
describe(*args, **kwargs) Descriptive summary statistics, excluding NaN values.
describe_by(*args, **kwargs) Descriptive summary statistics, excluding NaN values, along axes or for groups.
diff([axis, d, n, label]) Calculates the n-th order discrete difference along a given axis.
divnot0(other) Divides array by other, but returns 0.0 where other is 0.
drop_labels([axes]) Drops the labels from axes (replace those axes by “wildcard” axes).
dump([header]) Dump array as a 2D nested list
expand([target_axes, out, readonly]) Expands array to target_axes.
extend(axis, other) Adds an array to self along an axis.
filter([collapse]) Filters the array along the axes given as keyword arguments.
growth_rate([axis, d, label]) Calculates the growth along a given axis.
indexofmax([axis]) Returns indices of the maximum values along a given axis.
indexofmin([axis]) Returns indices of the minimum values along a given axis.
indicesofsorted([axis, ascending, kind]) Returns the indices that would sort this array.
insert(value[, before, after, pos, axis, label]) Inserts value in array along an axis.
labelofmax([axis]) Returns labels of the maximum values along a given axis.
labelofmin([axis]) Returns labels of the minimum values along a given axis.
labelsofsorted([axis, ascending, kind]) Returns the labels that would sort this array.
max(*axes_and_groups[, out, skipna, keepaxes]) Get maximum of array elements along given axes/groups.
max_by(*axes_and_groups[, out, skipna, keepaxes]) Get maximum of array elements for the given axes/groups.
mean(*axes_and_groups[, dtype, out, skipna, …]) Computes the arithmetic mean.
mean_by(*axes_and_groups[, dtype, out, …]) Computes the arithmetic mean.
median(*axes_and_groups[, out, skipna, keepaxes]) Computes the arithmetic median.
median_by(*axes_and_groups[, out, skipna, …]) Computes the arithmetic median.
min(*axes_and_groups[, out, skipna, keepaxes]) Get minimum of array elements along given axes/groups.
min_by(*axes_and_groups[, out, skipna, keepaxes]) Get minimum of array elements for the given axes/groups.
nonzero() Returns the indices of the elements that are non-zero.
percent(*axes) Returns an array with values given as percent of the total of all values along given axes.
percentile(q, *axes_and_groups[, out, …]) Computes the qth percentile of the data along the specified axis.
percentile_by(q, *axes_and_groups[, out, …]) Computes the qth percentile of the data for the specified axis.
posargmax(*args, **kwargs)
posargmin(*args, **kwargs)
posargsort(*args, **kwargs)
prepend(axis, value[, label]) Adds an array before self along an axis.
prod(*axes_and_groups[, dtype, out, skipna, …]) Computes the product of array elements along given axes/groups.
prod_by(*axes_and_groups[, dtype, out, …]) Computes the product of array elements for the given axes/groups.
ptp(*axes_and_groups[, out]) Returns the range of values (maximum - minimum).
ratio(*axes) Returns an array with all values divided by the sum of values along given axes.
rationot0(*axes) Returns a LArray with values array / array.sum(axes) where the sum is not 0, 0 otherwise.
reindex([axes_to_reindex, new_axis, …]) Reorder and/or add new labels in axes.
rename([renames, to, inplace]) Renames axes of the array.
reshape(target_axes) Given a list of new axes, changes the shape of the array.
reshape_like(target) Same as reshape but with an array as input.
set(value, **kwargs) Sets a subset of array to value.
set_axes([axes_to_replace, new_axis, inplace]) Replace one, several or all axes of the array.
set_labels([axis, labels, inplace]) Replaces the labels of an axis of array.
shift(axis[, n]) Shifts the cells of the array n-times to the left along axis.
sort_axes([axes, ascending]) Sorts axes of the array.
sort_axis(*args, **kwargs)
sort_values([key, axis, ascending]) Sorts values of the array.
split_axes([axes, sep, names, regex, sort, …]) Split axes and returns a new array
split_axis(*args, **kwargs)
std(*axes_and_groups[, dtype, ddof, out, …]) Computes the sample standard deviation.
std_by(*axes_and_groups[, dtype, ddof, out, …]) Computes the sample standard deviation.
sum(*axes_and_groups[, dtype, out, skipna, …]) Computes the sum of array elements along given axes/groups.
sum_by(*axes_and_groups[, dtype, out, …]) Computes the sum of array elements for the given axes/groups.
to_clipboard(*args, **kwargs) Sends the content of the array to clipboard.
to_csv(filepath[, sep, na_rep, transpose, …]) Writes array to a csv file.
to_excel([filepath, sheet_name, position, …]) Writes array in the specified sheet of specified excel workbook.
to_frame([fold_last_axis_name, dropna]) Converts LArray into Pandas DataFrame.
to_hdf(filepath, key, *args, **kwargs) Writes array to a HDF file.
to_series([dropna]) Converts LArray into Pandas Series.
transpose(*args) Reorder axes.
var(*axes_and_groups[, dtype, ddof, out, …]) Computes the unbiased variance.
var_by(*axes_and_groups[, dtype, ddof, out, …]) Computes the unbiased variance.
with_axes(*args, **kwargs)
with_total(*args[, op, label]) Add aggregated values (sum by default) along each axis.