P6.2.18000 m peaks

import numpy as np
from datetime import datetime, timedelta

EPOCH = datetime(1970, 1, 1)

dt = np.dtype(
    {
        "names": [
            "name",
            "height",
            "first_ascent",
            "first_winter_ascent",
            "latitude",
            "longitude",
        ],
        "formats": ["|S13", "u2", "f8", "f8", "f8", "f8"],
    }
)


def angle_str_to_float(s):
    """
    Convert an angle given in degrees, D, minutes, M, and seconds, S as a
    string 'DdMdSs' in to a float representing decimal degrees.
    """

    d, rem = s.split("d")
    m, rem = rem.split("m")
    s, rem = rem.split("s")
    return float(d) + float(m) / 60 + float(s) / 3600


def angle_float_to_str(abs_angle):
    """
    Convert a float representing an angle in degrees to a string of the form
    'DdMdSs' representing degrees, D, minutes, M, and seconds, S.

    """

    d = int(abs_angle)
    fmins = (abs_angle - d) * 60
    m = int(fmins)
    s = int(round((fmins - m) * 60))
    return "{D:d}d{M:d}m{S:d}s".format(D=d, M=m, S=s)


def longlat_str_to_float(s):
    """
    Convert a longitude or latitude given as a string 'DdMmSsZ' (Z=N, E, S or W)
    into a float representing decimal degrees.

    """

    sgn = {"N": 1, "E": 1, "S": -1, "W": -1}
    return sgn[s[-1]] * angle_str_to_float(s[:-1])


def latitude_float_to_str(angle):
    """
    Convert a latitude as a float between -90 and 90 degrees into a string
    giving degrees, minutes and seconds: 'DdMmSsZ' (Z=N or S).

    """

    hemisphere = "N" if angle >= 0 else "S"
    return angle_float_to_str(abs(angle)) + hemisphere


def longitude_float_to_str(angle):
    """
    Convert a longitude as a float between -180 and 180 degrees into a string
    giving degrees, minutes and seconds: 'DdMmSsZ' (Z=E or W).

    """

    hemisphere = "E" if angle >= 0 else "W"
    return angle_float_to_str(abs(angle)) + hemisphere


def date_str_to_float(s):
    """
    Converts a date represented as string formatted 'DD/MM/YYYY' to a number
    of seconds since "the epoch" (1/1/1970).
    """

    return (datetime.strptime(s, "%d/%m/%Y") - EPOCH).total_seconds()


def date_float_to_str(t):
    """
    Convert a time in seconds since the epoch to a string formatted
    'DD/MM/YYYY'

    """

    return datetime.strftime((EPOCH + timedelta(seconds=t)), "%d/%m/%Y")

peaks = np.genfromtxt(
    "ex6-2-b-mountain-data.txt",
    dtype=dt,
    skip_header=11,
    converters={
        2: date_str_to_float,
        3: date_str_to_float,
        4: longlat_str_to_float,
        5: longlat_str_to_float,
    },
    delimiter=(13, 5, 14, 12, 13, 11),
    skip_footer=1,
    autostrip=True,
)

ilowest = np.argmin(peaks["height"])
print(
    "The lowest 8000 m peak is {:s} at {:4d} m".format(
        peaks[ilowest]["name"].decode("utf-8"), peaks[ilowest]["height"]
    )
)

peaks.sort(order="latitude")
print(
    "The most Northerly peak is {:s} at {:s} deg North".format(
        peaks[-1]["name"].decode("utf-8"),
        latitude_float_to_str(peaks[-1]["latitude"]),
    )
)
print(
    "The most Southerly peak is {:s} at {:s} deg North".format(
        peaks[0]["name"].decode("utf-8"),
        latitude_float_to_str(peaks[0]["latitude"]),
    )
)

peaks.sort(order="longitude")
print(
    "The most Easterly peak is {:s} at {:s} deg East".format(
        peaks[-1]["name"].decode("utf-8"),
        longitude_float_to_str(peaks[-1]["longitude"]),
    )
)
print(
    "The most Westerly peak is {:s} at {:s} deg East".format(
        peaks[0]["name"].decode("utf-8"),
        longitude_float_to_str(peaks[0]["longitude"]),
    )
)

peaks.sort(order="first_ascent")
print(
    "Most recent first ascent: {:s} on {:s}".format(
        peaks[-1]["name"].decode("utf-8"),
        date_float_to_str(peaks[-1]["first_ascent"]),
    )
)

i = np.nanargmax(peaks["first_winter_ascent"])
print(
    "Most recent first winter ascent: {:s} on {:s}".format(
        peaks[i]["name"].decode("utf-8"),
        date_float_to_str(peaks[i]["first_winter_ascent"]),
    )
)


dt2 = np.dtype(
    {
        "names": ["name", "height", "first_ascent"],
        "formats": ["|S13", "u2", "|S10"],
    }
)
ordered_peaks = np.zeros(len(peaks), dtype=dt2)
ordered_peaks["name"] = peaks["name"]
ordered_peaks["height"] = peaks["height"] * 3.2808399
ordered_peaks["first_ascent"] = [
    date_float_to_str(t) for t in peaks["first_ascent"]
]
ordered_peaks = np.sort(ordered_peaks, order="height")[::-1]

print("+---------------+------------+--------------+")
print("| Peak          | height /ft | first ascent |")
print("+---------------+------------+--------------+")
for peak, height, first_ascent in ordered_peaks:
    print(
        "| {:13s} | {:^10d} | {:^12s} |".format(
            peak.decode("utf-8"), height, first_ascent.decode("utf-8")
        )
    )
print("+---------------+------------+--------------+")