Float cut Zeroes

[Rolig Loon]

The problem is that we have a sloppy language, and English speakers are not consistent in all corners of the Earth either.  I think Brits are more inclined to speak of the digits after the decimal point as "decimals".  That's not a common usage on this side of the Atlantic, but I can't swear that we have a real standard either.  Among scientific types, we always call them "significant figures", but that would confuse the average man on the street.

[Madelaine McMasters]

---

Rolig Loon wrote:

The problem is that we have a sloppy language, and English speakers are not consistent in all corners of the Earth either.  I think Brits are more inclined to speak of the digits after the decimal point as "decimals".  That's not a common usage on this side of the Atlantic, but I can't swear that we have a real standard either.  Among scientific types, we always call them "significant figures", but that would confuse the average man on the street.

---

In my circle, they're called:

• Base 02: significant bits
• Base 10: significant digits
• Base 16: significant nibbles

I'd never use the term "significant figure", except possibly to describe Richard Kiel.

[Rhonda Huntress]

Just to muddy the waters a little more, significant digits does not mean a fixed number of decimal places.

Pi to 3 significant digits is 3.14

Jose Altuve's batting average is .337

Speed of sound is 340 m/s

Speed of light is 3.00E8 m/s

 

At least that's the way I was taught in college more years ago than I care to say

 

[Rolig Loon]

---

Rhonda Huntress wrote:

Just to muddy the waters a little more, significant digits does not mean a fixed number of decimal places.

Pi to 3 significant digits is 3.14

Jose Altuve's batting average is .337

Speed of sound is 340 m/s

Speed of light is 3.00E8 m/s

 

At least that's the way I was taught in college more years ago than I care to say

 

---

I stand corrected.  My college days were farther back than yours, I'm sure, but I was taught the same.  We chemist types tend to be sloppier about numbers than the physics and math types, even physical chemists.

[Madelaine McMasters]

---

Rhonda Huntress wrote:

Just to muddy the waters a little more, significant digits does not mean a fixed number of decimal places.

Pi to 3 significant digits is 3.14

Jose Altuve's batting average is .337

Speed of sound is 340 m/s

Speed of light is 3.00E8 m/s

 

At least that's the way I was taught in college more years ago than I care to say

 

---

That's how I was taught.

It was my HP pocket calculator that drove home the difference between how scientists and normal people perceive significant digits. I can tell the thing to display in Scientific/Engineering/Fixed formats with a particular number of significant digits. Continuing your three significant digit demonstration on my HP-11C (I still have it)...

Avagadro's number (6.0221409e23):

• S = 6.02e23
• E = 602e21
• F = 6.02e23

My height in mm (1574.8):

• S = 1.57e3
• E = 1.57e3
• F = 1,574.80 (!)

For this reason, unless I'm checking bank statements, I use engineering or scientific notation. I find it easier to keep track of the size and precision of things when the mantissa suggests the precision and the exponent expresses the magnitude.

 

[Dora Gustafson]

 



"exponent" and "magnitude" triggered me:smileywink:

Or exponent and mantissa.

Give me back the slide rule, no batteries, readable everywhere and not controlled by Google or Microsoft

:smileysurprised::smileyvery-happy:

[Madelaine McMasters]

If you're old enough to have used a slipstick, your eyes are probably shot by now.

You need this...



[Madelaine McMasters]

Young Rolig...



[Rolig Loon]

Har har.

I used my Dad's slide rule until about 1969, when I finally shelled out $75 or so for a pocket calculator (with reverse Poilish notation).  I figured that I might need something more "precise" as a grad student than I had needed as an undergrad. That was the first of many technological missteps in my life.

[Madelaine McMasters]

---

Rolig Loon wrote:

reverse Poilish notation

---

When I encounter a calculator with an = key, I feel like tearing my hair out.

[Dora Gustafson]

---

Madelaine McMasters wrote:

---

Rolig Loon wrote:

reverse Poilish notation

---

When I encounter a calculator with an = key, I feel like tearing my hair out.

---

Is there any calculator but a RPN calculator ???

[Rolig Loon]

---

Dora Gustafson wrote:

---

Madelaine McMasters wrote:

---

Rolig Loon wrote:

reverse Poilish notation

---

When I encounter a calculator with an = key, I feel like tearing my hair out.

---

Is there any calculator but a RPN calculator ???

---

There sure was in 1969.  There was a serious debate about whether RPN was easier to use than algebraic notation, and HP had some rivals.  I still think algebraic notation makes more sense, but that battle was lost almost a half century ago. 

[Madelaine McMasters]

---

Rolig Loon wrote:

I still think algebraic notation makes more sense, but that battle was lost almost a half century ago. 

---

Algebraic notation absolutely makes more sense when you can write/type out the entire equation before hitting "=". But early calculator displays could only show a small number of digits, so you couldn't see the equation you were typing. That meant you'd have to remember all the parentheses as you went along. That's something I can't do even in a fancy text editor. You'd also need parenthesis keys and substantial (for the time) storage for the equation string.

RPN addressed all this with weird elegance. And if there's one thing I can't resist, it's weird elegance.

[Rolig Loon]

You're right, of course, which is why the battle was lost.  If you're looking at the period from today's perspective, it's hard to understand what all the shouting was about.  Remember, though, that we (and our ancestors for generations before) had been taught algebraic notation in high school math classes.  We had the importance of parentheses pounded into our little heads, so it was the only familiar way to write equations (and that's what we felt calculators were supposed to be doing).  Many people were not eager to cede the ground to a bunch of pointy-headed engineers from HP.

[Dora Gustafson]

I still use RPN and will to the day I die. Not so much on original calculators. Much more in apps that runs on PC, tablet and smart phone. In those apps the original Hewlett-Packard code lives on. Really, I would feel lost without it.

:smileysurprised::smileyvery-happy:

[Madelaine McMasters]

---

Rolig Loon wrote:

You're right, of course, which is why the battle was lost.  If you're looking at the period from today's perspective, it's hard to understand what all the shouting was about.  Remember, though, that we (and our ancestors for generations before) had been taught algebraic notation in high school math classes.  We had the importance of parentheses pounded into our little heads, so it was the only familiar way to write equations (and that's what we felt calculators were supposed to be doing).  Many people were not eager to cede the ground to a bunch of pointy-headed engineers from HP.

---

My head is not pointy, I'm wearing my hair up. And yours is a li'l flat where they pounded parentheses into it.

Plplplplpl!!!

[Rhonda Huntress]

In my high school we piled up rocks to count with.  That's the way it was done until the premier mathematician of the time, Ogg Flat-toes (a mammoth stepped on his foot) designed a method of making cuts on a stick.

[Madelaine McMasters]

---

Rhonda Huntress wrote:

In my high school we piled up rocks to count with.  That's the way it was done until the premier mathematician of the time, Ogg Flat-toes (a mammoth stepped on his foot) designed a method of making cuts on a stick.

---

This was before the invention of zero, right?

[wherorangi]

---

Qie Niangao wrote:

---

wherorangi wrote:

i had a quick nosey to follow up on what Qie said about 6-digit decimal precision in LSL

---

Oh eep! I

did

kinda say that, now that I look back, but I only

meant

 the fixed 6-trailing-digit representation when a float is cast to a string, as had been mentioned before in this thread. I just used "precision" imprecisely, with precisely the same imprecision as the function being labeled "fixedPrecision()" which might more

accurately

be called "fixedPoint()".

---

sorry. I didnt mean to infer that you said something you never did

you just triggered me to go off and have another read about it all

[wherorangi]

---

Rhonda Huntress wrote:

significant digits does not mean a fixed number of decimal places.

 

 

---

yes agree. Is exactly correct this

[JJValero Writer]

I use those two functions:

 

string float2Str(float in)
{
    return (string)((integer)in) + "." + (string)((integer)((in - (integer)in) * 100));
}

string vector2Str(vector v) 
{
    return "<" + float2Str(v.x) + ", " + float2Str(v.y) + ", " + float2Str(v.z) + ">";
}

default
{
    state_entry()
    {
    }

    touch_start(integer total_number)
    {
        vector v = <215.7509, 235.845750, 4001.50356>;
        
        llOwnerSay((string) v + "  =======  " + vector2Str(v));
    }
}