larray.Array.prepend

Array.prepend(axis, value, label=None) → Array[source]

Add an array before this array along an axis.

The two arrays must have compatible axes.

Parameters

axisaxis reference: Axis along which to prepend input array (value)
valuescalar or Array: Scalar or array with compatible axes.
labelstr, optional: Label for the new item in axis

Returns

Array: 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('sex', a.sum('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('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('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