# ------------------------------------------------------------------- # Import libraries # ------------------------------------------------------------------- import math # ------------------------------------------------------------------- # Constants # ------------------------------------------------------------------- # ------------------------------------------------------------------- # Global variables # ------------------------------------------------------------------- fileSize = "" totalBits = 0 networkSpeed = "" bitsPerSecond = 0.0 downloadTime = 0.0 # ------------------------------------------------------------------- # Subprograms # ------------------------------------------------------------------- # convert a string like "1.7 MiB" to the number of bits (e.g 14260634) def convertSizeToBits(pFileSize): parts = pFileSize.split(" ") quantity = float(parts[0]) unit = parts[1] if unit == "B": quantity *= 8 elif unit == "KiB": quantity *= 8 * 1024 elif unit == "MiB": quantity *= 8 * (1024 ** 2) elif unit == "GiB": quantity *= 8 * (1024 ** 3) elif unit == "TiB": quantity *= 8 * (1024 ** 4) else: print("Unknown unit, assuming you entered the number of bits") return math.ceil(quantity) # convert a string like "10 Mbps" to the number of bits per second (e.g. 10000000) def convertSpeedToBitsPerSecond(pSpeed): parts = pSpeed.split(" ") speed = float(parts[0]) unit = parts[1] if unit == "Kbps": speed *= 1000 elif unit == "Mbps": speed *= (1000 ** 2) elif unit == "Gbps": speed *= (1000 ** 3) elif unit == "Tbps": speed *= (1000 ** 4) else: print("Unknown unit, assuming you entered the number of bits per second") return speed # convert a time in seconds like 0.3 to a human readable string (e.g "300 ms") def convertTime(pTimeInSeconds): unit = "s" duration = pTimeInSeconds if duration < 1: unit = "ms" duration *= 1000 elif duration > 60: unit = "mins" duration /= 60 return "{:.1f} {}".format(duration, unit) # ------------------------------------------------------------------- # Main program # ------------------------------------------------------------------- print("Download speed calculator") # find the size of the file in bits fileSize = input("Enter file size (e.g. 1.7 MiB)") totalBits = convertSizeToBits(fileSize) print("Total number of bits: ", totalBits) # find the network speed in bits per second networkSpeed = input("Enter network speed (e.g. 55 Mbps)") bitsPerSecond = convertSpeedToBitsPerSecond(networkSpeed) print("Total bits per second: ", bitsPerSecond) downloadTime = totalBits / bitsPerSecond print("Download time:", convertTime(downloadTime)) # Challenges # 1) Replace every 1024 with a constant called BYTES_IN_KIBIBYTE # 2) Replace every 1000 with a constant called BYTES_IN_KILOBYTE # 3) Adjust convertTime to show very long times in hours rather than minutes