What Is the Max Length of a Python String

What is the max length of a Python string?

With a 64-bit Python installation, and (say) 64 GB of memory, a Python string of around 63 GB should be quite feasible, if not maximally fast. If you can upgrade your memory beyond 64 GB, your maximum feasible strings should get proportionally longer. (I don't recommend relying on virtual memory to extend that by much, or your runtimes will get simply ridiculous;-).

With a typical 32-bit Python installation, the total memory you can use in your application is limited to something like 2 or 3 GB (depending on OS and configuration), so the longest strings you can use will be much smaller than in 64-bit installations with high amounts of RAM.

How to work around Python 3 maximum string size?

Resolution: turns out to be the
data segment size limit

$ ulimit -d
4194304

For some reason, these 4294967296 B translate to a 2684354560 B per-allocation
cap in Python.

Setting this value to unlimited removes the cap. This can be done externally
by the parent process (e. g. ulimit -d unlimited from the shell) or
in Python itself using the
wrapper library for resource.h:

resource.setrlimit (resource.RLIMIT_DATA,
                    (resource.RLIM_INFINITY
                    ,resource.RLIM_INFINITY))

Apparently on more
recent kernels (4.7 and later) RLIMIT_DATA affects anonymous mappings too which
explains both the observed failure of large-ish allocations and my being
surprised.

Get max length of value inside a list which contains other lists

You could recursively search for all values in your data structure:

data = [{
        "name": "title",
        "value": "titel{TM} D3",
        "is_on_label": 1
    },
    [{
        "name": "title",
        "value": "titel{TM} D3",
        "is_on_label": 1,
        "sub_options": [
            {
                "value": "30V max 3A",
                "id_configuration_v": "1668"
            },
            {
                "value": "none none none none",
                "id_configuration_v": "1696"
            }
        ]
    }], 
    {
        "name": "DK in",
        "value": "24V max 2.5A",
        "is_on_label": 1,
        "id_configuration": 79,
        "options": [{
                "value": "30V max 3A",
                "id_configuration_v": "1668"
            },
            {
                "value": "none",
                "id_configuration_v": "1696"
            }
        ]
    }
]

def recur(data, count):
    if isinstance(data, list):
        for item in data:
            count = recur(item, count)
    elif isinstance(data, dict):
        for k, v in data.items():
            if k == 'value':
                count.append(len(v))
            else:
                count = recur(v, count)
    return count

result = recur(data, [])
print(max(result))

Out:

19

How to find maximum length of a given character in series from substring in python?

You may try this:

s = "..xxx..x.x.xxxxx.xx"
start = 0
maxcount = 0
for i in range(len(s)):
    # Using != "x" can work for strings which include other characters besides "."
    if s[i] != "x":
        # reset the start position
        start = i
        continue
    # update the result only if it is larger than current result
    if i - start > maxcount:
        maxcount = i - start
print(maxcount) # Output: 5

Python truncate a long string

info = (data[:75] + '..') if len(data) > 75 else data

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