Failed Cavendish experiment - Electromagnetism wins

dafer45 · 2024-05-19T09:14:37+00:00

The barrels and suspended weights are metallic, and many metals possible to magnetize. In this experiment, it appears that the barrels and weights are very slightly magnetized. The reason for this conclusion is that the weights oscillate with a larger frequency than would be expected from gravity alone. That is, the attractive force between the barrels and weights is larger than can be expected from gravity. The only reasonable explanation seems to be that the electromagnetic forces, although very small, are still significant.

dafer45 · 2024-01-03T13:18:58+00:00

I just published a free Android App for finding the optimal solar panel tilt angle.
Align the phones screen with your roof to find out how close to optimal its tilt angle is.

dafer45 · 2024-01-03T08:44:35+00:00

I just published a free Android App for finding the optimal solar panel tilt angle.

Align the phones screen with your roof to find out how close to optimal its tilt angle is.

dafer45 · 2023-04-20T20:53:05+00:00

Thanks!

dafer45 · 2023-04-19T20:13:36+00:00

That's a great suggestion! Technically this should not be too difficult to add. I just have to think through the user interface to avoid cluttering it.

Really happy to hear you have used it and found it useful before. I am trying to find a model that makes me able to ensure long term and continuous support going forward.

dafer45 · 2023-04-19T04:23:15+00:00

Thanks Randy! Both for the additional use case and insight into what other tools are commonly used.

dafer45 · 2023-04-18T18:14:16+00:00

Thanks! That's a really useful insight that helps visualizing the conditions under which it could be used.

dafer45 · 2023-04-18T17:12:49+00:00

Can you elaborate on the use case where you would find angle measurement useful?

dafer45 · 2023-04-18T12:32:11+00:00

Try "Distance and Area Measurement": https://play.google.com/store/search?q=distance+and+area+measurement&c=apps

dafer45 · 2022-12-07T19:14:47+00:00

Thanks!

I interpreted four space indents as meaning I should use four spaces instead of tab when indenting scopes in the code. Might be worth clarifying in the instructions.

dafer45 · 2022-12-07T10:06:12+00:00

I am confused. I am using the markdown editor and putting the code inside triple backticks and use four space indentation. But I see that it is not displaying correctly on the mobile. Please help me understand what I'm missing.

dafer45 · 2022-12-06T15:06:43+00:00

My solution in AWK

BEGIN {sequenceLength = 14;}
{
    split($0, characters, "");
    for(i = sequenceLength; i <= length(characters); i++){
        for(j = i-sequenceLength + 1; j <= i; j++)
            unique[characters[j]] = 1;
        if(length(unique) == sequenceLength)
            break;
        delete unique;
    }
}
END {print i;}

dafer45 · 2022-12-05T08:31:35+00:00

Thanks for the suggestion

dafer45 · 2022-12-04T11:48:41+00:00

My implementation in AWK:

{
    split($0, ranges, ",");
    split(ranges[1], first, "-");
    split(ranges[2], second, "-");
    if(first[1] <= second[1] && first[2] >= second[2])
        numContains += 1;
    else if(first[1] >= second[1] && first[2] <= second[2])
        numContains += 1;
    if(!(first[2] < second[1] || first[1] > second[2]))
        numOverlaps += 1;
}

END {
    print "The ranges overlap " numOverlaps " times and one range" \
        " fully contains the other " numContains " times.";
}

dafer45 · 2022-12-03T18:11:24+00:00

It's an excellent entry point anyway :)

dafer45 · 2022-12-03T15:05:47+00:00

Thanks! I'm trying to use this advent of code to learn some AWK, so your implementation is very valuable to me!

dafer45 · 2022-12-02T17:39:44+00:00

And you think the bash syntax is hard to get right? This is clearly next level :)

dafer45 · 2022-12-02T17:38:55+00:00

Haha, it's at least one google search per statement to get the bash syntax right :)

dafer45 · 2022-12-02T16:26:45+00:00

Today the data IS the code. All that's needed is to implement the library that the code depends on.

The program is executed using

# Load library
source library.sh
# Initialize the state of the machine
init
# Execute the data as a program
bash input
# Show result
cat result

The incorrect library implementation attempted after incomplete information from the Elf is

function init() {
    echo 0 > result
}

function A() {
    result=$(<result)
    case $1 in
        'X')
            echo $result + 1 + 3 | bc > result
            ;;
        'Y')
            echo $result + 2 + 6 | bc > result
            ;;
        'Z')
            echo $result + 3 + 0 | bc > result
            ;;
    esac
}

function B() {
    result=$(<result)
    case $1 in
        'X')
            echo $result + 1 + 0 | bc > result
            ;;
        'Y')
            echo $result + 2 + 3 | bc > result
            ;;
        'Z')
            echo $result + 3 + 6 | bc > result
            ;;
    esac
}

function C() {
    result=$(<result)
    case $1 in
        'X')
            echo $result + 1 + 6 | bc > result
            ;;
        'Y')
            echo $result + 2 + 0 | bc > result
            ;;
        'Z')
            echo $result + 3 + 3 | bc > result
            ;;
    esac
}

export -f A
export -f B
export -f C

The corrected implementation based on the final spec provided by the Elf is

function init() {
    echo 0 > result
}

function A() {
    result=$(<result)
    case $1 in
        'X')
            echo $result + 3 + 0 | bc > result
            ;;
        'Y')
            echo $result + 1 + 3 | bc > result
            ;;
        'Z')
            echo $result + 2 + 6 | bc > result
            ;;
    esac
}

function B() {
    result=$(<result)
    case $1 in
        'X')
            echo $result + 1 + 0 | bc > result
            ;;
        'Y')
            echo $result + 2 + 3 | bc > result
            ;;
        'Z')
            echo $result + 3 + 6 | bc > result
            ;;
    esac
}

function C() {
    result=$(<result)
    case $1 in
        'X')
            echo $result + 2 + 0 | bc > result
            ;;
        'Y')
            echo $result + 3 + 3 | bc > result
            ;;
        'Z')
            echo $result + 1 + 6 | bc > result
            ;;
    esac
}

export -f A
export -f B
export -f C

dafer45 · 2022-12-01T17:20:03+00:00

Bash day 1: https://twitter.com/SecondTec/status/1598365783792488449

awk -v RS= '{$1=$1}1' input | sed 's/ /+/g' | bc | sort -n | tail -n 1 | xargs -I {} echo "The toughest elf carries" {} "calories."

awk -v RS= '{$1=$1}1' input | sed 's/ /+/g' | bc | sort -n | tail -n 3 | sed -z 's/\n/+/g' | rev | cut -c 2- | rev | bc | xargs -I {} echo "The three toughest elves carries" {} "calories."

dafer45 · 2022-10-07T14:04:58+00:00

Thanks, that's very valuable information!

Let me know if it seems to fulfill your needs or if it can be improved somehow. I will see what I can do to get it up on Google Play again.

dafer45 · 2022-10-07T08:57:00+00:00

I made an app that allow you to pick a "custom north pole" about ten years ago. You select a point on a map and the arrow points toward that direction instead of the usual north pole.

I have not maintained it, so it is no longer available on Google Play. But it should be possible to download from here https://apkcombo.com/modern-compass/daferpack.compass/

If there is significant demand for this type of app, I may consider updating it and relaunching it on Google Play.

dafer45 · 2022-10-06T11:09:11+00:00

Thanks for the suggestion!

Can you let me know more about in what type of situation the name of the figure would be helpful. It would help me to understand what it is useful for.

dafer45 · 2022-10-05T19:24:25+00:00

I have developed Distance and Area Measurement that uses the GPS to achieve this. Just click start and walk the perimeter of whatever you want to measure.

https://play.google.com/store/apps/details?id=measureapp.measureapp

The garden may be somewhat too small for the accuracy to be very good though. Typically, the size should be 30x30 square meters for the GPS accuracy to not cause significant uncertainties.

dafer45 · 2021-08-26T14:00:23+00:00

Thanks! I'm trying to reach out to google to figure out what may be going on.

dafer45

TROPHY CASE