Loading...

verticapy.vDataFrame.apply

vDataFrame.apply(func: dict) vDataFrame

Applies each function of the dictionary to the input vDataColumns.

Parameters
func: dict

Dictionary of functions. The dictionary must be in the following format: {column1: func1, …, columnk: funck}. Each function variable must be composed of two flower brackets {}. For example, to apply the function x -> x^2 + 2, use “POWER({}, 2) + 2”.

vDataFrame

self

Examples

Let’s begin by importing VerticaPy.

import verticapy as vp

Hint

By assigning an alias to verticapy, we mitigate the risk of code collisions with other libraries. This precaution is necessary because verticapy uses commonly known function names like “average” and “median”, which can potentially lead to naming conflicts. The use of an alias ensures that the functions from verticapy are used as intended without interfering with functions from other libraries.

Let us work with the Titanic dataset:

from verticapy.datasets import load_titanic

vdf = load_titanic()
123
pclass
Integer
123
survived
Integer
Abc
Varchar(164)
Abc
sex
Varchar(20)
123
age
Numeric(8)
123
sibsp
Integer
123
parch
Integer
Abc
ticket
Varchar(36)
123
fare
Numeric(12)
Abc
cabin
Varchar(30)
Abc
embarked
Varchar(20)
Abc
boat
Varchar(100)
123
body
Integer
Abc
Varchar(100)
110male71.000PC 1760949.5042[null]C[null]22
210male45.00011378435.5TS[null][null]
310male[null]0011379831.0[null]S[null][null]
410male17.00011305947.1[null]S[null][null]
510male27.01013508136.7792C89C[null][null]
610male37.011PC 1775683.1583E52C[null][null]
710male31.010F.C. 1275052.0B71S[null][null]
810male50.010PC 17761106.425C86C[null]62
910female36.000PC 1753131.6792A29C[null][null]
1010male37.01011380353.1C123S[null][null]
1110male24.000PC 1759379.2B86C[null][null]
1210male45.0103697383.475C83S[null][null]
1310male40.0001120590.0B94S[null]110
1410male42.00011303842.5B11S[null][null]
1510male[null]001746351.8625E46S[null][null]
1610male42.01011378952.0[null]S[null]38
1710male[null]00PC 1760030.6958[null]C14[null]
1810male29.00011350130.0D6S[null]126
1910male46.0001305075.2417C6C[null]292
2010male54.0001746351.8625E46S[null]175
2110male47.00011379642.4[null]S[null][null]
2210male58.00235273113.275D48C[null]122
2310male45.50011304328.5C124S[null]166
2410male29.01011377666.6C2S[null][null]
2510male47.00011046552.0C110S[null]207
2610male38.000199720.0[null]S[null][null]
2710male22.000PC 17760135.6333[null]C[null]232
2810male31.000PC 1759050.4958A24S[null][null]
2910male50.0101350755.9E44S[null][null]
3010male56.0001776430.6958A7C[null][null]
3110male57.010PC 17569146.5208B78C[null][null]
3210female63.010PC 17483221.7792C55 C57S[null][null]
3310male61.0003696332.3208D50S[null]46
3410male21.0013528177.2875D26S[null]169
3510male51.001PC 1759761.3792[null]C[null][null]
3611female63.0101350277.9583D7S10[null]
3711female32.0001181376.2917D15C8[null]
3811female58.00011378326.55C103S8[null]
3911female44.000PC 1761027.7208B4C6[null]
4011female41.00016966134.5E40C3[null]
4111female53.000PC 1760627.4458[null]C6[null]
4211male36.001PC 17755512.3292B51 B53 B55C3[null]
4311female58.001PC 17755512.3292B51 B53 B55C3[null]
4411male11.012113760120.0B96 B98S4[null]
4511female76.0101987778.85C46S6[null]
4611female[null]0111350555.0E33S6[null]
4711female39.011PC 1775683.1583E49C14[null]
4811female27.012F.C. 1275052.0B71S3[null]
4911female[null]0017421110.8833[null]C4[null]
5011female35.000113503211.5C130C4[null]
5111female22.00111237859.4[null]C7[null]
5211female25.0101176555.4417E50C5[null]
5311male48.010PC 1757276.7292D33C3[null]
5411female35.0103697383.475C83SD[null]
5511male27.000PC 1757276.7292D49C3[null]
5611female24.0001176783.1583C54C7[null]
5711female52.0111274993.5B69S3[null]
5811female44.00111136157.9792B18C4[null]
5911female15.00124160211.3375B5S2[null]
6011male30.0101323657.75C78C11[null]
6111female31.01035273113.275D36C6[null]
6211female39.000PC 17758108.9C105C8[null]
6311female22.00111350961.9792B36C5[null]
6411male52.00011378630.5C104S6[null]
6511female43.00124160211.3375B3S2[null]
6611female33.00011015286.5B77S8[null]
6711male45.01116966134.5E34C3[null]
6811female40.01116966134.5E34C3[null]
6911male48.0101999652.0C126S5 7[null]
7011female[null]00PC 1758579.2[null]CD[null]
7111female35.000PC 17755512.3292[null]C3[null]
7211female60.01011081375.25D37C5[null]
7311male21.001PC 1759761.3792[null]CA[null]
7420male23.000C.A. 3103010.5[null]S[null][null]
7520male28.00024435826.0[null]S[null][null]
7620male60.0112975039.0[null]S[null][null]
7720female44.01024425226.0[null]S[null][null]
7820male29.010200326.0[null]S[null][null]
7920male18.000S.O.C. 1487973.5[null]S[null][null]
8020male18.000S.O.C. 1487973.5[null]S[null][null]
8120male54.0002840326.0[null]S[null][null]
8220male18.00023617113.0[null]S[null][null]
8320male36.00022923613.0[null]S[null]236
8420male34.0102866421.0[null]S[null][null]
8520male21.0102813311.5[null]S[null][null]
8620male21.0102813411.5[null]S[null][null]
8720male24.00023386613.0[null]S[null]155
8820male34.0001223313.0[null]S[null][null]
8920male30.00025065313.0[null]S[null]75
9020male44.00024874613.0[null]S[null]35
9120male49.01222084565.0[null]S[null][null]
9220male21.020S.O.C. 1487973.5[null]S[null][null]
9320male21.000S.O.C. 1487973.5[null]S[null][null]
9420female60.0102406526.0[null]S[null][null]
9520male24.020C.A. 3102931.5[null]S[null][null]
9620male22.020C.A. 3102931.5[null]S[null][null]
9720male35.00023373412.35[null]Q[null][null]
9820male31.000C.A. 1872310.5[null]S[null]165
9920male36.000SC/Paris 216312.875DC[null][null]
10020male[null]00SC/A.3 286115.5792[null]C[null][null]
Rows: 1-100 | Columns: 14

Note

VerticaPy offers a wide range of sample datasets that are ideal for training and testing purposes. You can explore the full list of available datasets in the Datasets, which provides detailed information on each dataset and how to use them effectively. These datasets are invaluable resources for honing your data analysis and machine learning skills within the VerticaPy environment.

Now let us apply two functions on the two different columns.

  • “boat”

  • “age”

For the “boat” column, we will encode it to a binary form which makes it easier to process in certain ML algorithms.

For the “age” column, we will fill in the missing values based on the columns “pclass” and “sex”.

vdf.apply(func = {
        "boat": "DECODE({}, NULL, 0, 1)",
        "age" : "COALESCE(age, AVG({}) OVER (PARTITION BY pclass, sex))",
    }
)
123
pclass
Int
100%
...
123
survived
Int
100%
Abc
home.dest
Varchar(100)
57%
11...0Montevideo, Uruguay
21...0Trenton, NJ
31...0[null]
41...0Montevideo, Uruguay
51...0Los Angeles, CA
61...0Lakewood, NJ
71...0Montreal, PQ
81...0Deephaven, MN / Cedar Rapids, IA
91...0New York, NY
101...0Scituate, MA
111...0[null]
121...0New York, NY
131...0[null]
141...0London / Middlesex
151...0Brighton, MA
161...0New York, NY
171...0New York, NY
181...0Springfield, MA
191...0Vancouver, BC
201...0Dorchester, MA

Note

Applying a function will alter the vDataColumn structure. It’s advisable to check the current relation of the vDataFrame to ensure it aligns with the intended outcome. For more information on achieving that, check out the current_relation documentation.

See also

vDataFrame.analytic() : Advanced Analytical functions.
vDataFrame.applymap() : Apply functions to all columns.