Numerical Precision

PhysicsLover999

What is Scratch's precision? I would make a program that finds machine epsilon, but I'm too lazy.

PhysicsLover999

Bump

PrincessPanda_test_

*googles “precision”*

the quality, condition, or fact of being exact and accurate.
“the deal was planned and executed with military precision”
synonyms: exactness, exactitude, accuracy, correctness, preciseness; More
marked by or adapted for accuracy and exactness.
modifier noun: precision
“a precision instrument”
technical
refinement in a measurement, calculation, or specification, especially as represented by the number of digits given.
plural noun: precisions
“this has brought an unprecedented degree of precision to the business of dating rocks”

Maybe 100%

Deerleg

PrincessPanda_test_ wrote:
*googles “precision”*

the quality, condition, or fact of being exact and accurate.
“the deal was planned and executed with military precision”
synonyms: exactness, exactitude, accuracy, correctness, preciseness; More
marked by or adapted for accuracy and exactness.
modifier noun: precision
“a precision instrument”
technical
refinement in a measurement, calculation, or specification, especially as represented by the number of digits given.
plural noun: precisions
“this has brought an unprecedented degree of precision to the business of dating rocks”

Maybe 100%

No, it's kind of off once you get to really big numbers and on

blocks.

PullJosh

Looks like 4.9406564584124654e-324.

MegaApuTurkUltra

Flash numbers adhere to the IEEE-754 double-precision standard which has a machine epsilon of 2.22e-16.
So I would assume Scratch's epsilon is the same.

TheHockeyist

14 significant figures is the max.

gtoal

PhysicsLover999 wrote:
What is Scratch's precision? I would make a program that finds machine epsilon, but I'm too lazy.

https://scratch.mit.edu/projects/70154644/

gtoal

PrincessPanda_test_ wrote:
*googles “precision”*

the quality, condition, or fact of being exact and accurate.

Precision is not accuracy. My computer says the time is 6pm, 51 minutes, 34.0016722047 seconds.

However it is about ten minutes off :-) So it is precise to a billionth of a second but accurate to only 10 minutes.

(In a similar vein, regular is not the same as frequent. “I bathe regularly” could mean twice a year, every six months to the day.)

Weasel-wording like this can be used to great effect, especially in court. For example if you question the reliability of a police radar detector, and they tell the judge under oath that “our radar detectors are checked regularly and are precise to one hundredth of a mile per hour” you'll know the follow-up questions to ask them :-)

G

Last edited by gtoal (July 11, 2015 23:59:19)

TheLogFather

Scratch uses standard double-precision floating-point numbers for variables that contain a number. That means it has 53 binary digits of precision, which corresponds to one part in 9 007 199 254 740 992.

See https://en.wikipedia.org/wiki/Double-precision_floating-point_format for more.

(Note that precision is a different thing to asking what is the smallest or largest value that a variable can hold, as others have mentioned, so if that's what you mean…)

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