[Query] The Hutterite Mile problem ...

[TiddlyTweeter]

I am not so good at maths. 

I do know that a Hutterite Mile is 8.4 Gorz and one Gorz is 0.195 of a UK Mile.

How in TW would I calculate the size in  UK Miles of one Hutterite Mile?

(To help you calculate The Hutterite mile song: 16 Horsepower - Hutterite Mile)

Just asking.

TT

[PMario]

On Thursday, April 29, 2021 at 1:47:55 PM UTC+2 TiddlyTweeter wrote:

I do know that a Hutterite Mile is 8.4 Gorz and one Gorz is 0.195 of a UK Mile.

You know:

1 HM = 8.4 Gorz

1 Gorz = 0.195 UKM

1 HM = 8.4 * 0.195 UKM

1 HM = 1.638 UKM

-m

[TiddlyTweeter]

PMario wrote:

You know:

1 HM = 8.4 Gorz

1 Gorz = 0.195 UKM

1 HM = 8.4 * 0.195 UKM

1 HM = 1.638 UKM

I love people like you who have a brain! 

Next question, HOW do I do that calculation in  TiddlyWiki?

Best wishes,

TT

[Mark S.]

There are actually two ways to  multiply things in TW now. The multiply operator, and the product operator. I always have to check the documentation to remember which is which. In your case, since you have only two items to multiply, you could use either approach:

<$list filter="8.4 0.195 +[product[]]"/>

<$list filter="8.4 +[multiply[0.195]]"/>

[TiddlyTweeter]

Ciao Mark S.

MUCH appreciated ... 

<$list filter="8.4 0.195 +[product[]]"/>

=1.6380000000000001

<$list filter="8.4 +[multiply[0.195]]"/>

=1.6380000000000001

Is there any way to "round" the OUTPUT to a more readable: 1.638  or 1.64 ?? 

(FYI, I just returned from walking the Hutterite Mile, under doctor's orders.)

Best wishes

TT

[Eric Shulman]

On Thursday, April 29, 2021 at 7:07:44 AM UTC-7 TiddlyTweeter wrote:

<$list filter="8.4 +[multiply[0.195]]"/> =1.6380000000000001

Is there any way to "round" the OUTPUT to a more readable: 1.638  or 1.64 ?? 

You can use the fixed[n] operator, where "n" is the number of desired decimal places.  Thus:

<$list filter="8.4 +[multiply[0.195]fixed[3]]"/>

see https://tiddlywiki.com/#fixed%20Operator

-e

[Mark S.]

The doctor told  grandma to walk 5 miles every day, and now we have no idea where the heck she is.

On Thursday, April 29, 2021 at 7:07:44 AM UTC-7 TiddlyTweeter wrote:

[TiddlyTweeter]

Thanks Eric

That does exactly what was needed for readability! 

Much appreciation you giving the code for that.

   <$list filter="8.4 +[multiply[0.195]fixed[3]]"/>

   =1.638

Best wishes

TT

[TiddlyTweeter]

Mark S. wrote:

The doctor told  grandma to walk 5 miles every day, and now we have no idea where the heck she is.

Hence the need for a Hutterite Mile calculator. 

I did not mention before that Hutterite Miles are connected to the Bermuda Triangle.

Best wishes

TT 

[Michael Wiktowy]

As an aside ... the problem has already answered but a general unit-conversion tip for next time ...

The best method that I have come across for thinking about unit conversion is to stack one unit over the other to form something that equals "one" and then multiply by "one" multiple times in order to cancel the units that you don't want.

Multiplying something by one doesn't charge it so you can then just write the equivalent of 1*1...=1 to get the right unit conversion factor without thinking too much about whether something needs to be multiplied or divided.

For instance:

1 HM = 8.4 Gorz can be re written as

1 = 1 HM/8.4 Gorz = 8.4 Gorz/1 HM

and similarly

1= 1 Gorz/0.195 UKM = 0.195 UKM/1 Gorz

So

1= (8.4 Gorz / 1 HM)(0.195 UKM / 1 Gorz)=(8.4/1)(0.195/1)(Gorz/HM)(UKM/Gorz)

Gorz cancels out so you are left with a relations between the units you have and the units you want

1=(8.4 * 0.195) UKM / 1 HM

1 HM = (8.4 * 0.195) UKM

This technique works well for much more complex unit chains. Food for thought.

/Mike

[TiddlyTweeter]

Inspired by Mark & you I'm working on a "Hutterite Mile Calculator". This will integrate "Smedleys" and "Gods". 

Gods are a measure of the distance in Smedleys from the nearest branch of Godina ...

Best, TT