To find the largest number in a list with python, a solution is to use the function max():

`>>> l = [4,7,9,4,1,6,9]`

`>>> max(l)`

`9`

which returns 9 here. To find the index, there is the function index(), example:

`>>> l.index(max(l))`

`2`

Note: this function only returns the first index found. To find all the indexes of a maximum value (if there is several occurrences of the maximum value), we can do like in this example:

`>>> indices = [i for i, x in enumerate(l) if x == max(l)]`

`>>> indices`

`[2, 6]`

To find if there is several times the max value in the list, a solution is to use the python function count(), example:

`>>> l = [4,7,9,4,1,6,9]`

`>>> max_value = max(l)`

`>>> max_value`

`9`

`>>> l.count(max_value)`

`2`

it is then possible to write a simple function that returns the index(es):

`>>> def get_indexes_max_value(l):`

`... max_value = max(l)`

`... if l.count(max_value) > 1:`

`... return [i for i, x in enumerate(l) if x == max(l)]`

`... else:`

`... return l.index(max(l))`

`...`

`>>> get_indexes_max_value(l)`

`[2, 6]`

### References

Liens | Site |
---|---|

Built-in Functions: max() | Python Doc |

Python List max() Method | Tutorial Point |

How to find positions of the list maximum? | stackoverflow |

Python Finding Index of Maximum in List | stackoverflow |

How to return the maximum element of a list in Python? | stackoverflow |

Python: Getting the max value of y from a list of objects | stackoverflow |

Pythonic way to find maximum value and its index in a list? | stack overflow |

Python's most efficient way to choose longest string in list? | stack overflow |

How does Python compare string and int? | stack overflow |