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Re: Initialize new variable array with nan or -9999 values [message #87648 is a reply to message #87645]

Thu, 20 February 2014 14:14

wlandsman
Messages: 743
Registered: June 2000

Senior Member

On Thursday, February 20, 2014 4:33:01 PM UTC-5, Paul van Delst wrote:
> On 02/20/14 13:36, John Correira wrote:

For large arrays, there is a speed advantage to using REPLICATE or MAKE_ARRAY in which the array is initialized with the correct value, as opposed to

fltarr(304,336,500) - 9999

in which the array is first initialized with zeros, and then 9999 is subtracted from each element. Most computers should be able easily handle a 50 Mb array, so in this case the speed difference would be a fraction of a second. But it is something to keep in mind when arrays are large enough that a factor of two speed improvement matters. --Wayne

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[Message index]

		Initialize new variable array with nan or -9999 values By: morganlsilverman on Thu, 20 February 2014 10:31
		Re: Initialize new variable array with nan or -9999 values By: David Fanning on Thu, 20 February 2014 10:35
		Re: Initialize new variable array with nan or -9999 values By: David Fanning on Thu, 20 February 2014 10:37
		Re: Initialize new variable array with nan or -9999 values By: chris_torrence@NOSPAM on Thu, 20 February 2014 13:11
		Re: Initialize new variable array with nan or -9999 values By: David Fanning on Thu, 20 February 2014 13:28
		Re: Initialize new variable array with nan or -9999 values By: John Correira on Thu, 20 February 2014 10:36
		Re: Initialize new variable array with nan or -9999 values By: Paul Van Delst[1] on Thu, 20 February 2014 13:33
		Re: Initialize new variable array with nan or -9999 values By: David Fanning on Thu, 20 February 2014 13:46
		Re: Initialize new variable array with nan or -9999 values By: Paul Van Delst[1] on Thu, 20 February 2014 14:00
		Re: Initialize new variable array with nan or -9999 values By: wlandsman on Thu, 20 February 2014 14:14
		Re: Initialize new variable array with nan or -9999 values By: Heinz Stege on Thu, 20 February 2014 17:36
		Re: Initialize new variable array with nan or -9999 values By: David Fanning on Thu, 20 February 2014 20:11
		Re: Initialize new variable array with nan or -9999 values By: John Correira on Fri, 21 February 2014 06:47
		Re: Initialize new variable array with nan or -9999 values By: David Fanning on Fri, 21 February 2014 06:58

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