iode.Variables.__isub__

Variables.__isub__(other)[source]

subtract other from the current (subset of) Variables object.

Parameters:
other: int, float, numpy ndarray, pandas Series, pandas DataFrame, larray Array or iode Variables

If other is an int or a float, subtract the scalar from all values of the current (subset of) Variables object. If other is a numpy ndarray, the shape of the ndarray must be compatible with the current (subset of) Variables object. Specifically, the number of rows must be equal to the number of variables and the number of columns must be equal to the number of periods. If other is a pandas Series, it must represent either a single variable or a single period. If other is a pandas DataFrame, it must represent the same variables names and periods as the current (subset of) Variables object. Specifically, the index of the DataFrame must be equal to the variables names and the columns of the DataFrame must be equal to the periods. If other is an larray Array, its last axis must be equal to the periods and be named ‘time’. If the Array has more than two axes, the first n-1 axes are combined to form the variables names. The first (combined) axis must be equal to the variables names. If other is an iode Variables object, it must share the same sample and represent the same set of variables names as self.

Warnings
——–
Subtracting a numpy ndarray to a Variables object is not recommended as there is no compatibility check
between for the names and periods. The result is not guaranteed to be the one you expected.
This possibility is provided for speed reasons (when the database or the subset is large).

Examples

>>> import numpy as np
>>> import pandas as pd
>>> import larray as la
>>> from iode import SAMPLE_DATA_DIR
>>> from iode import variables, NA, Sample
>>> variables.load(f"{SAMPLE_DATA_DIR}/fun.var")
Loading .../fun.var
394 objects loaded
>>> vars_subset = variables["A*", "1991Y1:1995Y1"]
>>> vars_subset.names
['ACAF', 'ACAG', 'AOUC', 'AOUC_', 'AQC']
>>> vars_subset
Workspace: Variables
nb variables: 5
filename: ...fun.var
description: Modèle fun - Simulation 1
sample: 1991Y1:1995Y1
mode: LEVEL

 name       1991Y1  1992Y1  1993Y1  1994Y1  1995Y1
ACAF         26.24   30.16   34.66    8.16  -13.13
ACAG        -30.93  -40.29  -43.16  -16.03  -41.85
AOUC          1.02    1.03    1.03    1.05    1.05
AOUC_         0.96    0.97    0.98    0.99    1.00
AQC           1.06    1.11    1.15    1.16    1.16
>>> # subtract a scalar from all values of the current subset of a Variables object
>>> vars_subset -= 2.0
>>> vars_subset
Workspace: Variables
nb variables: 5
filename: ...fun.var
description: Modèle fun - Simulation 1
sample: 1991Y1:1995Y1
mode: LEVEL

 name       1991Y1  1992Y1  1993Y1  1994Y1  1995Y1
ACAF             24.24   28.16   32.66    6.16  -15.13
ACAG            -32.93  -42.29  -45.16  -18.03  -43.85
AOUC             -0.98   -0.97   -0.97   -0.95   -0.95
AOUC_            -1.04   -1.03   -1.02   -1.01   -1.00
AQC          -0.94       -0.89   -0.85   -0.84   -0.84
>>> # subtract a (subsets of) a Variables object from the current one
>>> vars_subset -= vars_subset
>>> vars_subset
Workspace: Variables
nb variables: 5
filename: ...fun.var
description: Modèle fun - Simulation 1
sample: 1991Y1:1995Y1
mode: LEVEL

 name       1991Y1  1992Y1  1993Y1  1994Y1  1995Y1
ACAF          0.00        0.00    0.00    0.00    0.00
ACAG          0.00        0.00    0.00    0.00    0.00
AOUC          0.00        0.00    0.00    0.00    0.00
AOUC_         0.00        0.00    0.00    0.00    0.00
AQC           0.00        0.00    0.00    0.00    0.00
>>> # subtract a pandas Series from a single variable
>>> series = pd.Series([1.0, 2.0, 3.0, 4.0, 5.0], index=vars_subset.periods_as_str)
>>> series
1991Y1    1.0
1992Y1    2.0
1993Y1    3.0
1994Y1    4.0
1995Y1    5.0
dtype: float64
>>> vars_subset["ACAF"] -= series
>>> vars_subset["ACAF"]
Workspace: Variables
nb variables: 1
filename: ...fun.var
description: Modèle fun - Simulation 1
sample: 1991Y1:1995Y1
mode: LEVEL

name        1991Y1  1992Y1  1993Y1  1994Y1  1995Y1
ACAF         -1.00   -2.00   -3.00   -4.00   -5.00
>>> # subtract a pandas Series from the subset corresponding to a single period
>>> series = pd.Series([1.0, 2.0, 3.0, 4.0, 5.0], index=vars_subset.names)
>>> series
ACAF     1.0
ACAG     2.0
AOUC     3.0
AOUC_    4.0
AQC      5.0
dtype: float64
>>> vars_subset[:, "1995Y1"] -= series
>>> vars_subset[:, "1995Y1"]
Workspace: Variables
nb variables: 5
filename: ...fun.var
description: Modèle fun - Simulation 1
sample: 1995Y1:1995Y1
mode: LEVEL

 name       1995Y1
ACAF         -6.00
ACAG         -2.00
AOUC         -3.00
AOUC_        -4.00
AQC          -5.00
>>> # subtract a pandas DataFrame from the current subset of the Variables object  
>>> data = np.array([[1.0, 2.0, 3.0, 4.0, 5.0], 
...                  [6.0, 7.0, 8.0, 9.0, 10.0], 
...                  [11.0, 12.0, 13.0, 14.0, 15.0], 
...                  [16.0, 17.0, 18.0, 19.0, 20.0], 
...                  [21.0, 22.0, 23.0, 24.0, 25.0]],)
>>> df = pd.DataFrame(data, index=vars_subset.names, columns=vars_subset.periods_as_str) 
>>> df
       1991Y1  1992Y1  1993Y1  1994Y1  1995Y1
ACAF      1.0     2.0     3.0     4.0     5.0
ACAG      6.0     7.0     8.0     9.0    10.0
AOUC     11.0    12.0    13.0    14.0    15.0
AOUC_    16.0    17.0    18.0    19.0    20.0
AQC      21.0    22.0    23.0    24.0    25.0
>>> vars_subset -= df
>>> vars_subset
Workspace: Variables
nb variables: 5
filename: ...fun.var
description: Modèle fun - Simulation 1
sample: 1991Y1:1995Y1
mode: LEVEL

 name       1991Y1  1992Y1  1993Y1  1994Y1  1995Y1
ACAF         -2.00   -4.00   -6.00   -8.00  -11.00
ACAG         -6.00   -7.00   -8.00   -9.00  -12.00
AOUC        -11.00  -12.00  -13.00  -14.00  -18.00
AOUC_       -16.00  -17.00  -18.00  -19.00  -24.00
AQC         -21.00  -22.00  -23.00  -24.00  -30.00
>>> # subtract an larray Array from the current subset of the Variables object
>>> axis_names = la.Axis(name="names", labels=vars_subset.names)
>>> axis_time = la.Axis(name="time", labels=vars_subset.periods_as_str)
>>> array = la.Array(data, axes=(axis_names, axis_time))
>>> array
names\time  1991Y1  1992Y1  1993Y1  1994Y1  1995Y1
      ACAF     1.0     2.0     3.0     4.0     5.0
      ACAG     6.0     7.0     8.0     9.0    10.0
      AOUC    11.0    12.0    13.0    14.0    15.0
     AOUC_    16.0    17.0    18.0    19.0    20.0
       AQC    21.0    22.0    23.0    24.0    25.0
>>> vars_subset -= array
>>> vars_subset
Workspace: Variables
nb variables: 5
filename: ...fun.var
description: Modèle fun - Simulation 1
sample: 1991Y1:1995Y1
mode: LEVEL

 name       1991Y1  1992Y1  1993Y1  1994Y1  1995Y1
ACAF         -3.00   -6.00   -9.00  -12.00  -16.00
ACAG        -12.00  -14.00  -16.00  -18.00  -22.00
AOUC        -22.00  -24.00  -26.00  -28.00  -33.00
AOUC_       -32.00  -34.00  -36.00  -38.00  -44.00
AQC         -42.00  -44.00  -46.00  -48.00  -55.00
   
>>> # WARNING: subtracting a numpy ndarray to a (subset of a) Variables object is not recommended 
>>> #          as there is no compatibility check between for the names and periods.
>>> #          The result is not guaranteed to be the one you expected.
>>> #          This possibility is provided for speed reasons 
>>> #          (when dealing with large subsets/databases).
>>> # subtract a numpy 1D ndarray from a single variable
>>> data = np.array([1.0, 2.0, 3.0, 4.0, 5.0])
>>> vars_subset["ACAF"] -= data
>>> vars_subset["ACAF"]
Workspace: Variables
nb variables: 1
filename: ...fun.var
description: Modèle fun - Simulation 1
sample: 1991Y1:1995Y1
mode: LEVEL

name        1991Y1  1992Y1  1993Y1  1994Y1  1995Y1
ACAF         -4.00   -8.00  -12.00  -16.00  -21.00

>>> # subtract a numpy 1D ndarray from the subset corresponding to a single period
>>> vars_subset[:, "1995Y1"] -= data
>>> vars_subset[:, "1995Y1"]
Workspace: Variables
nb variables: 5
filename: ...fun.var
description: Modèle fun - Simulation 1
sample: 1995Y1:1995Y1
mode: LEVEL

 name       1995Y1
ACAF        -22.00
ACAG        -24.00
AOUC        -36.00
AOUC_       -48.00
AQC         -60.00
        
>>> # subtract a numpy 2D ndarray from the current (subset of the) Variables object
>>> data = np.array([[1.0, 2.0, 3.0, 4.0, 5.0], 
...                  [6.0, 7.0, 8.0, 9.0, 10.0], 
...                  [11.0, 12.0, 13.0, 14.0, 15.0], 
...                  [16.0, 17.0, 18.0, 19.0, 20.0], 
...                  [21.0, 22.0, 23.0, 24.0, 25.0]])
>>> vars_subset -= data
>>> vars_subset
Workspace: Variables
nb variables: 5
filename: ...fun.var
description: Modèle fun - Simulation 1
sample: 1991Y1:1995Y1
mode: LEVEL

 name       1991Y1  1992Y1  1993Y1  1994Y1  1995Y1
ACAF         -5.00  -10.00  -15.00  -20.00  -27.00
ACAG        -18.00  -21.00  -24.00  -27.00  -34.00
AOUC        -33.00  -36.00  -39.00  -42.00  -51.00
AOUC_       -48.00  -51.00  -54.00  -57.00  -68.00
AQC         -63.00  -66.00  -69.00  -72.00  -85.00