Is using Math.pow faster than multiplying myself?

Hi all,
Is it faster to use Math.pow to calculate a power than to, say, multiply it myself in a loop? How about if I'm just doing a square -- is it faster to use Math.pow(x,2) than x * x?
I noticed that the pow method in StrictMath has the keyword "native." Does this mean it's being done by the operating system? Does it mean it's being done directly in the hardware?
Thanks!
Tim

TimQuinn wrote:
This is in an inner-loop deep in a simulation, so I'd like it to be as fast as possible. From the above, I'm gathering that I should keep using pow for my ^8 calculation, but substitute a simple multiplication for my ^2 calculation.Not necessarily. Remember that N^8 = ((N^2)^2)^2. The Math.pow algorithm will very likely use this optimization, but you can too.
Related question: does it make any difference at all in these kinds of operations if I use floats or doubles? In terms of speed, I mean, not precision.Actual answer to all of your questions: try all of the possibilities in your simulation and see what actually happens.

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thanks.
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^ As was my ill-advised original response to the @OP. :D

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Anyone else have issues getting a full charge on iPhone 4S after updating to ios 7.0?
It's draining noticable faster - battery drains faster than it charges now so that unless you turn off the screen you end up with less charge than when you docked it. Same goes for regular 30 pin cable to 1Amp wall charger without the dock.
I left mine over night on the iPhone dock and it still only reached 92%
Never had issues on ios 6.
Even with the screen dimmed back to 50% (like I had it set for ios 6),
Battery was at 45% before updated yesterday and even though it was docked and charging during update was at 36% after the update, and kept dropping the longer I had it connected.
Does anyone know for sure if ios 7 is using the A5 cpu differently? maybe running it faster or using more power than on ios 6?
Rebooted my iPhone 4S a few times after updating, nosame issue. Was able to use Safari but unable to download from itunes or app store. They asked or my password, but it said "could not connect to app store, please try again". perhaps due to so many users updating yesterday
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I noticed that even though screen lock timeout was set for 2 mins, it was prompting for code immediately. Had to change to 5 mins, since the 2 minute to lock option has been removed in ios 7.
Thanks,
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BOILERPLATE TEXT:
Note that this is boilerplate text.
If you give complete and detailed information about your setup and the issue at hand,
such as your platform (Mac or Win),
exact versions of your OS, of Photoshop (not just "CS6", but something like CS6v.13.0.6) and of Bridge,
your settings in Photoshop > Preference > Performance
the type of file you were working on,
machine specs, such as total installed RAM, scratch file HDs, total available HD space, video card specs, including total VRAM installed,
what troubleshooting steps you have taken so far,
what error message(s) you receive,
if having issues opening raw files also the exact camera make and model that generated them,
if you're having printing issues, indicate the exact make and model of your printer, paper size, image dimensions in pixels (so many pixels wide by so many pixels high). if going through a RIP, specify that too.
etc.,
someone may be able to help you (not necessarily this poster, who is not a Windows user).
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Is this logging code faster than using a standard logging API like log4J

is this logging code faster than using a standard logging API like log4J or the logging API in java 1.4
As you can see my needs are extremely simple. write some stuff to text file and write some stuff to dos window.
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* @author Stephen
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* @since June 2002
import java.io.*;
import java.net.*;
import java.util.*;
import java.text.*;
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In general I'd guess that a small, custom thing will be faster than a large, generic thing with a lot of options. That is, unless the writer of the small program have done something stupid, og the writer of the large program have done something very smart.
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In the end, there is really only one way to find out: Test it.

Video faster than audio when use Adobe Media Encoder to convert f4v to mp4

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I'm sure I read this somewhere on the internet.
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As a rule of thumb, I'd say if it's unused for less than a day or so, standby makes more sense. There's a discussion at the link below which also fails to give a definitive answer but has some interetsing comments.
http://apple.stackexchange.com/questions/7588/for-least-power-usage-should-i-tur n-off-or-put-my-mac-to-sleep

HT4060 I'm having some problems with my ipad and charging it. I am having to leave it in charge for a lot longer, but when I take it out and want to use it the battery is still not completely full and goes down a lot faster than usual

I'm having some problems with my ipad and charging it. I am having to leave it in charge for a lot longer, but when I take it out and want to use it the battery is still not completely full and goes down a lot faster than usual. The other day, I had charged my iPad overnight so that I could take it to university with me for the day, and when I had switched it on the next day the battery was on 5% and I had not used it since charge.

Your battery may be dying. THey are only good for so many charges/discharges. If you have an apple store near by make an appointment and have them check itout

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hi
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in general, what can the possible reasons be for JVM to run faster than CLR?
thanks
double G = 6.6726E-11;
double difference = 0.0;
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Interesting N-Body problem that treats accelerations as scalars.
Anyway, if there is no optimisation for small integer powers in the Math.pow() method, then I'd expect almost all the time is used there or in its equivalent in .NET. Hardly a meaningful test of relative performance.
Try using (difference * difference) instead.
Sylvia.

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I mostly browse the internet and compose written documents, and keynote presentations.
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Hi brosephb,
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Can I charge my new ipod using firewire power adapter?

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I'm quite sure I've done sufficient research on this, as well as many other people in this industry, and these forums. Perhaps it is you that might want to do a little more reading.

Is using Math.pow faster than multiplying myself?

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