Premeds Calculator

"""
The Premedicant Dose for animal type is the weight of animal multipled by drug dose rate, divided
by drugconcertration.
"""

from __future__ import division

drug_concentrations = {"meloxicam": 5.0, "amoxicillin clavulanic acid": 32.5, "ketamine": 100,
    "enrofloxacin 2.5 percent solution": 25, "enrofloxacin 5.0 percent solution": 50}

rates = {
    'dog': {"meloxicam": [0.2], "amoxicillin clavulanic acid": [8.75,12.5], "ketamine": [5.0,7.0]},
    'cat': {"meloxicam": [0.2], "amoxicillin clavulanic acid": [8.75,12.5], "ketamine": [5.0,7.5]},
    'rabbit': {"meloxicam": [0.6], "ketamine": [20], "enrofloxacin 2.5 percent solution": [10.0, 15.0, 20.0, 25.0], "enrofloxacin 5.0 percent solution": [10.0, 15.0, 20.0, 25.0]}
}

# maximum weight inputs
weight_max = {"dog": 100.0, "cat": 15.0, "rabbit": 15.0}
valid_species = [ name for name in weight_max.keys() ]

def input_species():
    # force input of species. Keep looping until valid.
    while True:
        species = raw_input("\nEnter species as one of: {}".format(valid_species))
        species = species.lower().strip()
        if species in rates.iterkeys():
            return species

        # match input with species dict, or first letter of species
        # else keep looping.return species
        for animal in rates:
            if species == animal or species == animal[:1]:
                return species

        print("\nEnter species as one of: {}".format(valid_species))


def input_weight():
    # force input of species. Keep looping until valid.
    while True:
        try:
            weight_float = float(raw_input("\nEnter weight as float: "))

            # valid, but in range?
            if (weight_float > 0.0 and weight_float < weight_max[species]):
                return weight_float
            else:
                print("Error, weight not in range: 0.0 - {} for a {}".format(weight_max[species], species))

        except ValueError:
            print("Error, invalid weight is not a float: ", weight_float)
            continue


while True:
    # Grab two inputs and return premeds.
    species = input_species()
    weight_float = input_weight()

    # Calculate Vet's premed dosage based on animal type
    # weight * dose_rate  / drug_concentration

    print("Calculate:\n\tanimal = {} \n\tweight = {}\n".format(species, weight_float))

    # iterate every drug, since none was chosen for this animal
    for animal in valid_species:
        for drug in rates[animal]:
            print("\nRates for drug={} uses: {}".format(drug, rates[animal][drug]))
            for rate in rates[animal][drug]:
                dosage_calculated = (weight_float * rate) / drug_concentrations[drug]
                print("\tRate = {:.2f} ml, calculated dosage = {:.2f} ml".format(rate, dosage_calculated))

    if raw_input("\nTo run again, type: 'Y': ").lower() not in 'y':
        break