larray.LArray.prepend¶

LArray.prepend(axis, value, label=None)[source]¶

Adds an array before self along an axis.

The two arrays must have compatible axes.

Parameters:

axis : axis reference

Axis along which to prepend input array (value)

value : LArray

Array with compatible axes.

label : str, optional

Label for the new item in axis

Returns:

LArray

Array expanded with ‘value’ at the start of ‘axis’.

Examples

>>> a = ones('nat=BE,FO;sex=M,F')
>>> a
nat\sex    M    F
     BE  1.0  1.0
     FO  1.0  1.0
>>> a.prepend(X.sex, a.sum(X.sex), 'M+F')
nat\sex  M+F    M    F
     BE  2.0  1.0  1.0
     FO  2.0  1.0  1.0
>>> a.prepend(X.nat, 2, 'Other')
nat\sex    M    F
  Other  2.0  2.0
     BE  1.0  1.0
     FO  1.0  1.0
>>> b = zeros('type=type1,type2')
>>> b
type  type1  type2
        0.0    0.0
>>> a.prepend(X.sex, b, 'Other')
nat  sex\type  type1  type2
 BE     Other    0.0    0.0
 BE         M    1.0    1.0
 BE         F    1.0    1.0
 FO     Other    0.0    0.0
 FO         M    1.0    1.0
 FO         F    1.0    1.0