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Day 1

Sonar Sweep

view the Advent of Code 2021 Day 1 challenge

Setup

# Setup - load any packages
import numpy as np

Load the data

data_raw = np.genfromtxt('day1_data.txt',delimiter=',')

data_raw

array([ 140.,  154.,  165., ..., 3591., 3595., 3596.])

Part 1

How many measurements are larger than the previous measurement?

# create a numpy array
data = data_raw

# create additional numpy array
# duplicate the first element at the start of the array to offset the elements
data2=np.insert(data, 0, data[0], axis=0)

# duplicate the last element at the end of the original data array so it is the same length as data2
data=np.append(data, data[-1])

print(data)
print(data2)

[ 140.  154.  165. ... 3595. 3596. 3596.]
[ 140.  140.  154. ... 3591. 3595. 3596.]

# Compare each of the elements in data array to see if it is greater than the element in data2 array
compare=data>data2

# view the results
print(compare)

# Get a count
sum(compare)

[False  True  True ...  True  True False]

1298

Part 2

view the Advent of Code 2021 Day 1 challenge Part 2

def CompareSonarList(list1, list2):
    return (sum(list1)<sum(list2))

results = []

for i in range(len(data_raw)-1):
    #print (data_raw[i:i+3], data_raw[i+1:i+4])
    results.append(CompareSonarList(data_raw[i:i+3], data_raw[i+1:i+4]))


print(sum(results))

1248