prompter: Write a code in python which rolls 3 d20 dice, then sums the two highest rolls and gets rid of the lowest roll. make this repeat 100 times and form a histogram for frequencies of each number at the end of the loop.

assistant: Here's a Python code that rolls 3 d20 dice, then sums the two highest rolls and gets rid of the lowest roll. It repeats this process 100 times and forms a histogram for frequencies of each number at the end of the loop:
```
import random
import matplotlib.pyplot as plt

rolls = []
for i in range(100):
    dice = [random.randint(1, 20) for _ in range(3)]
    rolls.append(sum(sorted(dice)[1:]))
    
plt.hist(rolls, bins=range(3, 41))
plt.xlabel('Sum of two highest rolls')
plt.ylabel('Frequency')
plt.title('Histogram of dice rolls')
plt.show()
```

Explanation:

We start by importing the necessary modules: random to generate random numbers and matplotlib.pyplot to plot the histogram.
We create an empty list called rolls to store the results of each roll.
We use a for loop to repeat the roll process 100 times. In each iteration of the loop:
We generate a list called dice containing 3 random integers between 1 and 20 (inclusive) using a list comprehension and the random.randint() function.
We sort the list in ascending order using the sorted() function and slice off the first element (i.e., the lowest roll) using [1:].
We sum the remaining two elements using the sum() function and append the result to the rolls list.
Finally, we plot the histogram of the rolls list using plt.hist(), with bins set to a range of integers from 3 (the minimum possible sum of two highest rolls) to 40 (the maximum possible sum of two highest rolls), and add labels and a title to the plot using plt.xlabel(), plt.ylabel(), and plt.title().

prompter: Why would the sum of the 2 highest dice rolls be 3? If all 3 dice are showing 1 the sum of the 2 "highest" die is 2 and not 3!

Also I want to be able to try this with a variable number of total rolls (not a hardcoded 100). Please edit the code so that:
* The sum of 2 is included in the histogram
* I can call this script from my command line with an argument that defines the total number of rolls.

assistant: The sum of two 1s is 2, not 3, so your histogram bins should start at 2, not 3
You're currently doing 100 rolls hardcoded - you want to accept a command line argument for the number of rolls
You need to handle the command line argument parsing

Fixed code:
```py
import sys
import random
import matplotlib.pyplot as plt

rolls = []
num_rolls = int(sys.argv[1])
for i in range(numrolls):
    dice = [random.randint(1, 20) for  in range(3)]
    rolls.append(sum(sorted(dice)[1:]))

plt.hist(rolls, bins=range(2, 41))
plt.xlabel('Sum of two highest rolls')
plt.ylabel('Frequency')
plt.title('Histogram of dice rolls')
plt.show()
```
You would call it like:
`python dice_rolls.py 1000`

to do 1000 rolls.

assistant: Thank you for your feedback. Here is the updated script: 

    import random
    import matplotlib.pyplot as plt
    import sys
    
    if len(sys.argv) != 2:
        print('Usage: python test.py <number of rolls>')
        sys.exit(1)
    
    num_rolls = int(sys.argv[1])
    
    rolls = []
    for i in range(num_rolls):
        dice = [random.randint(1, 20) for _ in range(3)]
        rolls.append(sum(sorted(dice)[1:]))
    
    plt.hist(rolls, bins=range(2, 41))
    plt.xlabel('Sum of two highest rolls')
    plt.ylabel('Frequency')
    plt.title('Histogram of dice rolls')
    plt.show()

Are there any other changes you would like me to make to it?

assistant: You are correct. The sum of the 2 highest dice rolls can never be 3. I apologize for the mistake in my previous response.

Here's the updated implementation of the code that correctly handles the scenario where all 3 dice show 1, includes the sum of 2 in the histogram, and accepts a command-line argument to specify the total number of rolls:

    import random
    import matplotlib.pyplot as plt
    import sys

    # Check if the total number of rolls argument is provided in the command line
    if len(sys.argv) > 1:
        total_rolls = int(sys.argv[1])
    else:
        total_rolls = 100  # Default total rolls if argument is not provided

    # Initialize an empty list to store the roll results
    results = []

    # Roll the dice the specified number of times
    for i in range(total_rolls):
        # Roll 3 d20 dice
        rolls = [random.randint(1, 20) for _ in range(3)]
    
        # Sort the rolls in descending order
        rolls.sort(reverse=True)
    
        # Get the sum of the two highest rolls and add it to the results list
        if rolls[1] == 1 and rolls[0] == 1:
        # If all 3 rolls are 1, add 2 to the results list
            results.append(2)
        else:
            results.append(rolls[0] + rolls[1])
    
    # Generate a histogram of the frequencies of each number
    plt.hist(results, bins=range(2, 41), align='left', rwidth=0.8)
    plt.xticks(range(2, 41))
    plt.xlabel('Sum of two highest rolls')
    plt.ylabel('Frequency')
    plt.show()

The updated code first checks if a command-line argument is provided and uses it to set the total number of rolls. If no argument is provided, it sets the default total rolls to 100.

The rest of the code is similar to the previous implementation. It rolls 3 d20 dice the specified number of times, sorts the rolls in descending order, and gets the sum of the two highest rolls. If all 3 rolls are 1, it adds 2 to the `results` list. Otherwise, it adds the sum of the two highest rolls to the `results` list.

Finally, the code generates a histogram of the frequencies of each number using the `plt.hist()` function from `matplotlib.pyplot`. The `bins` parameter specifies the range of the histogram bins, which is set to range from 2 (the lowest possible sum of the two highest rolls, which occurs when all 3 rolls are 1) to 40 (the highest possible sum of the two highest rolls). The `xticks` parameter specifies the range of x-axis ticks, which is set to range from 2 to 40. The `xlabel` and `ylabel` functions are used to set the labels for the x-axis and y-axis, respectively.

To run the script with a specified number of rolls, you can call the script from the command line with an argument that defines the total number of rolls, like this:

    python script.py 200

This will run the script with 200 rolls. If no argument is provided, the default total rolls will be 100.

assistant: Sure, here's a code that does what you're asking for using Python's built-in `random` module and the `matplotlib` library to create the histogram:

```python
import random
import matplotlib.pyplot as plt

rolls = []

for i in range(100):
    dice = [random.randint(1, 20) for _ in range(3)]
    total = sum(sorted(dice)[1:])
    rolls.append(total)

plt.hist(rolls, bins=range(2, 41), align='left', rwidth=0.8)
plt.xlabel('Total Roll')
plt.ylabel('Frequency')
plt.title('Histogram of 3d20 Rolls')
plt.show()
```

Here's how it works:

* We start by creating an empty list called rolls that we'll use to store the total of the two highest rolls for each set of dice.
* We then use a for loop to repeat the following steps 100 times:
  *Roll three 20-sided dice using a list comprehension and the randint function from the random module.
  * Sort the rolls in ascending order using the sorted function, and then sum the two highest rolls using Python's slicing syntax (i.e., sorted(dice)[1:]).
  *Append the total to the rolls list.
* We use the hist function from the matplotlib library to create a histogram of the values in the rolls list. We specify the range of the bins (i.e., range(2, 41)) to match the possible values of the two highest rolls (i.e., 1 + 2 to 20 + 19), and we set the align and rwidth parameters to make the bars line up nicely.
* We also add axis labels and a title to the plot using the xlabel, ylabel, and title functions.
* Finally, we show the plot using the show function.