# Calculate the Max in Python

You need to calculate the maximum value in a numerical dataset in Python.

## Step-by-step tutorial

There are multiple ways to do this, depending on your data representation.

### Approach 1: List data

Python has a built-in max function for calculating the maximum value in a list:

>>> data = [3, 1, 4, 1, 5, 9, 2, 6, 5, 3]
>>> max(data)
9

### Approach 2: Pandas DataFrame

You can calculate the max for whole DataFrame, or else just a single column. Here's how to do the whole DataFrame:

>>> import pandas as pd
>>> precip = pd.read_csv('precip-central-park.csv')
>>> precip
YEAR   JAN   FEB   MAR   APR   MAY   JUN   JUL   AUG   SEP   OCT   NOV   DEC  ANNUAL
0    1869  2.53  6.87  4.61  1.39  4.15  4.40  3.20  1.76  2.81  6.48  2.03  5.02   45.25
1    1870  4.41  2.83  3.33  5.11  1.83  2.82  3.76  3.07  2.52  4.97  2.42  2.18   39.25
2    1871  2.07  2.72  5.54  3.03  4.04  7.05  5.57  5.60  2.34  7.50  3.56  2.24   51.26
3    1872  1.88  1.29  3.74  2.29  2.68  2.93  7.83  6.29  2.95  3.35  4.08  3.18   42.49
4    1873  5.34  3.80  2.09  4.16  3.69  1.28  4.61  9.56  3.14  2.73  4.63  2.96   47.99
..    ...   ...   ...   ...   ...   ...   ...   ...   ...   ...   ...   ...   ...     ...
146  2015  5.23  2.04  4.72  2.08  1.86  4.79  3.98  2.35  3.28  3.91  2.01  4.72   40.97
147  2016  4.41  4.40  1.17  1.61  3.75  2.60  7.02  1.97  2.79  4.15  5.41  2.89   42.17
148  2017  4.83  2.48  5.25  3.84  6.38  4.76  4.19  3.34  2.00  4.18  1.58  2.21   45.04
149  2018  2.18  5.83  5.17  5.78  3.53  3.11  7.45  8.59  6.19  3.59  7.62  6.51   65.55
150  2019  3.58  3.14  3.87  4.55  6.82  5.46  5.77  3.70  0.95  6.15  1.95  7.09   53.03

[151 rows x 14 columns]
>>> precip.max()
YEAR      2019.00
JAN         10.52
FEB          6.87
MAR         10.69
APR         14.01
MAY         10.24
JUN         10.26
JUL         11.89
AUG         18.95
SEP         16.85
OCT         16.73
NOV         12.41
DEC          9.98
ANNUAL      80.56
dtype: float64

A single column (based on a Pandas Series) works the way you'd expect:

>>> precip['MAR'].max()
10.69