Rank: 555 based on 147 downloads (last 30 days) and 7 files submitted
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Drew Compston

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Stanford University
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37.42940139770508, -122.1732025146484

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01 Apr 2013 Screenshot International Reference Ionosphere (IRI) Model Get the International Reference Ionosphere (IRI) output parameters. Author: Drew Compston iri, international referen..., geophysics, physics 36 8
  • 5.0
5.0 | 2 ratings
15 Feb 2013 Screenshot MSIS-E-90 NRL MSIS-E-90 atmosphere model. Author: Drew Compston msis, atmosphere, exosphere, orbit decay, atmospheric drag, aerospace 18 0
02 Nov 2012 Screenshot International Geomagnetic Reference Field (IGRF) Model Compute the Earth's magnetic field at points in space according to the IGRF model. Author: Drew Compston earths magnetic field, igrf, international geomagn..., geophysics, physics 54 4
  • 4.5
4.5 | 4 ratings
02 Nov 2012 Two's Complement Binary Strings Convert between binary fixed point two's complement strings and decimal numbers. Author: Drew Compston binary, twos complement, fixed point 10 0
06 Sep 2012 Fresnel Integral Compute Fresnel integral. Author: Drew Compston mathematics, physics, fresnel integral 23 0
Comments and Ratings by Drew View all
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01 Apr 2013 International Reference Ionosphere (IRI) Model Get the International Reference Ionosphere (IRI) output parameters. Author: Drew Compston

Derek, there were some problems in some of the time sweeps (unrelated to number of points) which I just fixed and uploaded. Longitude sweeps can also be tricky: First of all, they only work for altitude = 100, and something like [-2 -1 0 1 2] will not work because the negative numbers wrap around to near 360, resulting in a big gap. Please feel free to post any other specific examples where maybe it should calculate a linear sweep but doesn't.

17 Nov 2012 freezeColors / unfreezeColors Use multiple colormaps per figure! Version 2, now works for many types of objects, not only images. Author: John Iversen

This function worked well for me using R2012a and imagesc and surf. Haven't tried for other types of plots like scatter (in one of the comments).

24 Aug 2012 NEARESTPOINT (sep 2012) NEARESTPOINT - find the nearest value in another vector Author: Jos (10584)

I love this function and use it all the time. I did find two, possibly degenerate cases:

1. nearestpoint(1, []) errors at line 91.
2. nearestpoint([1 2], NaN) errors at line 116. This I fixed by changing that line to:
D(q) = abs(dx - reshape(y(IND(q)), size(dx))) ;

22 May 2012 International Reference Ionosphere (IRI) Model Get the International Reference Ionosphere (IRI) output parameters. Author: Drew Compston

Krishna, as you pointed out, there was a bug in my geocentric coordinate conversion which might have caused your confusion. Look at it when the new version I just uploaded gets approved. When the input COORD is 'geoc', input LATITUDE is elevation, input LONGITUDE is azimuth, and input ALTITUDE is range.

10 Mar 2012 Another Particle Swarm Toolbox Implementation of a PSO algorithm with the same syntax as the Genetic Algorithm Toolbox. Author: Sam

Comments and Ratings on Drew's Files View all
Updated File Comment by Comments Rating
04 Apr 2013 International Reference Ionosphere (IRI) Model Get the International Reference Ionosphere (IRI) output parameters. Author: Drew Compston Derek

Drew, thank you! That fixed my problems! Thanks again for this awesome code!

01 Apr 2013 International Reference Ionosphere (IRI) Model Get the International Reference Ionosphere (IRI) output parameters. Author: Drew Compston Compston, Drew

Derek, there were some problems in some of the time sweeps (unrelated to number of points) which I just fixed and uploaded. Longitude sweeps can also be tricky: First of all, they only work for altitude = 100, and something like [-2 -1 0 1 2] will not work because the negative numbers wrap around to near 360, resulting in a big gap. Please feel free to post any other specific examples where maybe it should calculate a linear sweep but doesn't.

27 Mar 2013 International Reference Ionosphere (IRI) Model Get the International Reference Ionosphere (IRI) output parameters. Author: Drew Compston Derek

Actually, I retract my statement saying "I believe this is because sweepstop = min([sweep(end) + sweepstep/10, sweepmax]); should be sweepstop = [sweep(end) + sweepstep/10, sweepmax];"

27 Mar 2013 International Reference Ionosphere (IRI) Model Get the International Reference Ionosphere (IRI) output parameters. Author: Drew Compston Derek

Thank you for submitting this code and updating it. On that note, I believe there is an issue with sweeping linear arrays greater than 500 elements. The program should enter into case {1 2 3 4 5 6 7} however, it instead moves to case 8. If the adjustment is made to force the program into case {1 2 3 4 5 6 7}, sweeping still fails. I believe this is because sweepstop = min([sweep(end) + sweepstep/10, sweepmax]); should be sweepstop = [sweep(end) + sweepstep/10, sweepmax];

11 Oct 2012 International Reference Ionosphere (IRI) Model Get the International Reference Ionosphere (IRI) output parameters. Author: Drew Compston Brandon

On line 496 in iri.m, there is a conversion from time into hours (in decimal form), and I think there is a mistake. The conversion divides seconds by 360 when I think it should be 3600.

Top Tags Applied by Drew
physics, geophysics, aerospace, astronomy, atmosphere
Files Tagged by Drew View all
Updated   File Tags Downloads
(last 30 days)
Comments Rating
01 Apr 2013 Screenshot International Reference Ionosphere (IRI) Model Get the International Reference Ionosphere (IRI) output parameters. Author: Drew Compston iri, international referen..., geophysics, physics 36 8
  • 5.0
5.0 | 2 ratings
15 Feb 2013 Screenshot MSIS-E-90 NRL MSIS-E-90 atmosphere model. Author: Drew Compston msis, atmosphere, exosphere, orbit decay, atmospheric drag, aerospace 18 0
02 Nov 2012 Screenshot International Geomagnetic Reference Field (IGRF) Model Compute the Earth's magnetic field at points in space according to the IGRF model. Author: Drew Compston earths magnetic field, igrf, international geomagn..., geophysics, physics 54 4
  • 4.5
4.5 | 4 ratings
02 Nov 2012 Two's Complement Binary Strings Convert between binary fixed point two's complement strings and decimal numbers. Author: Drew Compston binary, twos complement, fixed point 10 0
06 Sep 2012 Fresnel Integral Compute Fresnel integral. Author: Drew Compston mathematics, physics, fresnel integral 23 0

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