Posted: 23rd Sep 2021 15:34
I'm reading the tutorial on data types about ranges. The positive and negative integers at the top of the example I understand, but the real numbers part I'm lost.

I Know in algebra 3E is read 3*E, but this whole real example is confusing. Can someone explain it in simple terms of possible?

+ Code Snippet
INTEGER Range : -2,147,483,648 to 2,147,483,647
REAL Range : 3.4E +/- 38 (7 significant figures)
Posted: 23rd Sep 2021 18:22
That's called scientific notation.

3.4 x 10^38

These are the upper and lower limits
Posted: 23rd Sep 2021 23:15
hese are the upper and lower limits


I understand math as it is normally written, but how you got 10^38 out of what is there I'm clueless. Scientific natation I no nother about and how to read it. I have have done all the way up to algebra 5. I never had the chance to go one more step up to trig or even higher though.

They really should do the tutorial for type ranges in a more simple explanation so people who don't have a clue about scientific notation can understand ranges
Posted: 24th Sep 2021 0:00
The limits are 1.8e-38.7 to 3.4e38.7, now if you understand what that means; eh.
Now the key thing to note is the 7 Significant Figures... because this denotes the PRECISION that is available.
Sure with the Exponent we can describe very large or very small numbers., but the crux is that these are only to the 7 most important values; or more specifically this is what will be accurately calculated; as more figures will be returned but will exponentially become less accurate due to rounding errors and affine alignment.

I mean think of a Digital Volume Control... you will usually get 100 Points of Volume out of it., were-as an Analog Knob can allow you to be more refined but this is at the cost of allowing for Precise Volume Control.

The same is true between an Integer and Floating Point., greater range / fine tuning but at the loss of precision.
Posted: 24th Sep 2021 1:49
32 bits less one for the sign. So it's the largest number you can represent using 31 bits
Posted: 24th Sep 2021 2:48
mean think of a Digital Volume Control... you will usually get 100 Points of Volume out of it., were-as an Analog Knob can allow you to be more refined but this is at the cost of allowing for Precise Volume Control.


I understand this, but not the number with "e" at the end. Does the "e" represent exponent or to the power of? If so then I understand now.
Posted: 24th Sep 2021 5:05
E is for exponent. This is basically a convenient way to represent large numbers that can't typically be displayed or where you can't represent a superscript (the exponent).

This is a pretty well known and accepted notation, I suggest you google it and read up on it. Do they not teach scientific notation in school anymore?
Posted: 24th Sep 2021 10:59
Do they not teach scientific notation in school anymore?


I couldn't tell you, I'm 56 years old. I graduated in 1984. Lol. I have been out of school for awhile and you tend to forget things sometimes if you don't use the knowledge very often
Posted: 25th Sep 2021 17:03
10^38 comes from the fact that there are 7 bits for the exponent in a 32 bit floating point (8 if you include the sign to allow for either really large or really small numbers). 10^38 is roughly equal to 2^127 (127 being the largest number representable using 7 bits).
Posted: 27th Sep 2021 6:35
I couldn't tell you, I'm 56 years old. I graduated in 1984


lol my bad. I'll get off your lawn now!
Posted: 3rd Oct 2021 7:06
lol my bad. I'll get off your lawn now!


Your fine lol