Rank: 331 based on 196 downloads (last 30 days) and 3 files submitted

John Fuller

E-mail: idrawzalot@gmail.com
Lat/Long: 39.01221084594727, -77.43099975585938

Personal Profile:: I'm an aerospace systems engineer in the Washington, D.C. region. I have a B.S. and an M.S. in Aerospace Engineering from NCSU, and I've been using Matlab in both work and school since 2004. I'm almost considering using it to do my taxes.
Professional Interests:: Aerospace, GN&C, trajectory analysis, orbit dynamics

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Files Posted by John					View all 1 - 3 of 3
Updated		File	Tags	Downloads (last 30 days)	Comments	Rating
25 Jan 2013		Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param. Author: John Fuller	aerospace, rotation, 3d, direction cosines, euler angle, dcm	105	32	4.58333 4.6 \| 12 ratings
12 Sep 2012		Euler angle, DCM, Quaternion, and Euler Vector Conversion/Teaching GUI A GUI that helps users learn how Euler angles and other rotational data relate to one another. Author: John Fuller	euler angles, quaternion, dcm, euler, aerospace, gui	73	1	4.0 4.0 \| 2 ratings
01 Dec 2011		Newton-Raphson Iterative Solver for Systems of Equations An N-R iterative root-finder for systems of N equations and N unknowns. Author: John Fuller	newton, raphson, iterative, solver, systems of equations, root	18	2	2.0 2.0 \| 1 rating

Comments and Ratings by John		View all 1 - 5 of 13
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22 Jan 2013	Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param. Author: John Fuller	Paolo, I have incorporated a fix to address that bug, which is largely similar to your snippet. Thanks for catching this!
28 Aug 2012	KML Toolbox v2.6 Create KML/KMZ files and view them in Google Earth. Supports 3D models, contours, overlays, and more Author: Rafael Oliveira
17 Aug 2012	KML Toolbox v2.6 Create KML/KMZ files and view them in Google Earth. Supports 3D models, contours, overlays, and more Author: Rafael Oliveira	Rafael, I get the following error when I run the quiver function example snippet: k = kml('my kml file'); % Create a sample quiver plot in the kml file [x,y] = meshgrid(-5:.2:5,-2:.15:2); z = x .* exp(-x.^2 - y.^2) + y.sin(x); [px,py] = gradient(z,.2,.15); k.quiver(5x,10y,8px,8*py) % Save the kml and open it in Google Earth k.save; ??? Undefined function or variable 'id'. Error in ==> kml.quiver at 61 target(i) = f.plot(long2,lat2, 'altitude',arg.altitude,... Any thoughts?
11 Apr 2012	Vectorized Analytic Two Body Propagator (Kepler Universal Variables) Analytic propagation routine uses universal variables to solve a single formula for all orbit types Author: Darin Koblick	Downloaded but can't seem to unzip. Not sure if the file is corrupted, may want to check.
20 Oct 2011	Newton-Raphson Iterative Solver for Systems of Equations An N-R iterative root-finder for systems of N equations and N unknowns. Author: John Fuller	No humor with this one :)

Comments and Ratings on John's Files			View all 1 - 5 of 42
Updated	File	Comment by	Comments	Rating
29 Jan 2013	Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param. Author: John Fuller	de Leva, Paolo	That's bad. My second last posting was totally deleted by MATLAB Central, possibly because it contained special characters... I wrote that in your latest release of SpinCalc, you introduced a new bug in line 238. In that line (which I cannot copy here because it contains special characters), you should use the element-by-element OR operator (single vertical bar), rather than the short-circuit OR operator (double bar) which does not work when N is greater than 1. In short, you should go back to previous version of line 238. Please also check my 4 advices posted yesterday.
29 Jan 2013	Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param. Author: John Fuller	de Leva, Paolo	MATLAB Central keeps truncating everything I write after special characters. In my latest posting, the logical OR operators and whatever was written after them were deleted. Anyway, you can check previous version of line 238. You should use the element-by-element OR operator (single vertical bar), rather than the short-circuit OR operator (double bar).
28 Jan 2013	Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param. Author: John Fuller	de Leva, Paolo	I have been trying to post this text, but MATLAB Central keeps truncating it. Here is the complete version, with special characters removed: 1) Please update the release version number. 2) Line 388: OUTPUT=mod([psi,theta,phi]180/pi,360); Proposed change: OUTPUT=[psi,theta,phi]180/pi; THETA is computed in your code either using ACOS or ASIN. In MATLAB, both ACOS(X) and ASIN(X) return values within a limited range. For -1 =< X =< 1, ACOS_X = ACOS(X)(180/pi) always returns values ranging from 0 to 180 degrees. This almost coincides with the range (from 0.1 to 179.9 degrees) accepted by SpinCalc as input for THETA (with EA type 2 rotations). Similarly, for -1 =< X =< 1, ASIN_X = ASIN(X)(180/pi) always returns angles ranging from -90 to 90 degrees. Again, this almost coincides with the range (from -89.9 to 89.9 degrees) accepted by SpinCalc as input for THETA (with EA type 1 rotations). If X < -1 or X > 1, then the result ACOS_X or ASIN_X is complex, and SpinCalc returns an error message. Computing MOD(ACOS_X,360) is useless, because THETA = MOD(ACOS_X, 360) = ACOS_X More importantly, computing MOD(ASIN_X,360) is inconsistent with other parts of your code, because for negative values of ASIN_X (i.e. -90 =< ASIN_X < 0 degrees) THETA = MOD(ASIN_X, 360) == ASIN_X + 360 which means that, for negative values of ASIN_X, THETA will range from 270 =< ASIN_X < 360 degrees, which is considered to be out range when used as input for SpinCalc (with EA type 1 rotations). 3) Line 396: sing_chk=... [find(abs(theta180/pi) < 0.1); ... find(abs(theta180/pi-180) < 0.1);... find(abs(theta180/pi-360)) < 0.1]; Proposed change: sing_chk=... [find(abs(theta180/pi) < 0.1); ... find(abs(theta180/pi-180) < 0.1);... find(abs(theta180/pi-360) < 0.1)]; 4) Every time you convert a Nx1 or Nx3 array containing angles in radians into an array containing angles in degrees, or vice versa (and you do it a lot of times in your code, including the above mentioned lines 388 and 396), you use this syntax: Y = X180/pi or Y = Xpi/180 This way, you repeat the division (by PI or by 180) N times. I suggest you to use this sintax, which is much more efficient as it computes the division only once (see also functions deg2rad and rad2deg): Y = X(180/pi) or Y = X(pi/180).
28 Jan 2013	Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param. Author: John Fuller	de Leva, Paolo	I am trying to post this text, containing a few notes about SpinCalc, but the web site keeps truncating it. Here is the complete version, with a few special characters removed: 1) Please update the release version number. 2) Line 388: OUTPUT=mod([psi,theta,phi]180/pi,360); Proposed change: OUTPUT=[psi,theta,phi]180/pi; THETA is computed in your code either using ACOS or ASIN. In MATLAB, both ACOS(X) and ASIN(X) return values within a limited range. For -1 <= X <= 1, ACOS_X = ACOS(X)(180/pi) always returns values ranging from 0 to 180 degrees. This almost coincides with the range (from 0.1 to 179.9 degrees) accepted by SpinCalc as input for THETA (with "input type" EA### and "Euler type" 2). Similarly, for -1 <= X <= 1, ASIN_X = ASIN(X)(180/pi) always returns angles ranging from -90 to 90 degrees. Again, this almost coincides with the range (from -89.9 to 89.9 degrees) accepted by SpinCalc as input for THETA (with "input type" EA### and "Euler type" 1). If X > 1 or X < -1, then the result ACOS_X or ASIN_X is complex, and SpinCalc returns an error message. Computing MOD(ACOS_X,360) is useless, because THETA = MOD(ACOS_X, 360) = ACOS_X More importantly, computing MOD(ASIN_X,360) is inconsistent with other parts of your code, because for negative values of ASIN_X (i.e. -90 <= ASIN_X < 0 degrees) THETA = MOD(ASIN_X, 360) == ASIN_X + 360 which means that, for negative values of ASIN_X, THETA will range from 270 <= ASIN_X < 360 degrees, which is considered to be out range when used as input for SpinCalc (with "input type" EA### and "Euler type" 1). 3) Line 396: sing_chk=... [find(abs(theta180/pi) < 0.1); ... find(abs(theta180/pi-180) < 0.1);... find(abs(theta180/pi-360)) < 0.1]; Proposed change: sing_chk=... [find(abs(theta180/pi) < 0.1); ... find(abs(theta180/pi-180) < 0.1);... find(abs(theta180/pi-360) < 0.1)]; 4) Every time you convert a Nx1 or Nx3 array containing angles in radians into an array containing angles in degrees, or vice versa (and you do it a lot of times in your code, including the above mentioned lines 388 and 396), you use this syntax: Y = X180/pi or Y = Xpi/180 This way, you repeat the division (by PI or by 180) N times. I suggest you to use this sintax, which is much more efficient as it computes the division only once (see also functions deg2rad and rad2deg): Y = X(180/pi) or Y = X(pi/180).
28 Jan 2013	Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param. Author: John Fuller	de Leva, Paolo	I am trying to post this text, containing a few notes about SpinCalc, but the web site keeps truncating it. Here is the complete version, with a few special characters removed: 1) Please update the release version number. 2) Line 388: OUTPUT=mod([psi,theta,phi]180/pi,360); Proposed change: OUTPUT=[psi,theta,phi]180/pi; THETA is computed in your code either using ACOS or ASIN. In MATLAB, both ACOS(X) and ASIN(X) return values within a limited range. For -1<=X<=1, ACOS_X = ACOS(X)(180/pi) always returns values ranging from 0 to 180 degrees. This almost coincides with the range (from 0.1 to 179.9 degrees) accepted by SpinCalc as input for THETA (with "input type" EA### and "Euler type" 2). Similarly, for -1<=X<=1, ASIN_X = ASIN(X)(180/pi) always returns angles ranging from -90 to 90 degrees. Again, this almost coincides with the range (from -89.9 to 89.9 degrees) accepted by SpinCalc as input for THETA (with "input type" EA### and "Euler type" 1). If X>1 or X<-1, then the result ACOS_X or ASIN_X is complex, and SpinCalc returns an error message. Computing MOD(ACOS_X,360) is useless, because THETA = MOD(ACOS_X, 360) = ACOS_X More importantly, computing MOD(ASIN_X,360) is inconsistent with other parts of your code, because for negative values of ASIN_X (i.e. -90<=ASIN_X<0 degrees) THETA = MOD(ASIN_X, 360) == ASIN_X + 360 which means that, for negative values of ASIN_X, THETA will range from 270<=ASIN_X<360 degrees, which is considered to be out range when used as input for SpinCalc (with "input type" EA### and "Euler type" 1). 3) Line 396: sing_chk=... [find(abs(theta180/pi)<0.1); ... find(abs(theta180/pi-180)<0.1);... find(abs(theta180/pi-360))<0.1]; Proposed change: sing_chk=... [find(abs(theta180/pi)<0.1); ... find(abs(theta180/pi-180)<0.1);... find(abs(theta180/pi-360)<0.1)]; 4) Every time you convert a Nx1 or Nx3 array containing angles in radians into an array containing angles in degrees, or vice versa (and you do it a lot of times in your code, including the above mentioned lines 388 and 396), you use this syntax: Y = X180/pi or Y = Xpi/180 This way, you repeat the division (by pi or by 180) N times. I suggest you to use this sintax, which is much more efficient as it computes the division only once: Y = X(180/pi) or Y = X(pi/180).

Top Tags Applied by John	1 - 5 of 21
aerospace, dcm, quaternion, rotation, 3d

Files Tagged by John					View all 1 - 3 of 3
Updated		File	Tags	Downloads (last 30 days)	Comments	Rating
25 Jan 2013		Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param. Author: John Fuller	aerospace, rotation, 3d, direction cosines, euler angle, dcm	105	32	4.58333 4.6 \| 12 ratings
12 Sep 2012		Euler angle, DCM, Quaternion, and Euler Vector Conversion/Teaching GUI A GUI that helps users learn how Euler angles and other rotational data relate to one another. Author: John Fuller	euler angles, quaternion, dcm, euler, aerospace, gui	73	1	4.0 4.0 \| 2 ratings
01 Dec 2011		Newton-Raphson Iterative Solver for Systems of Equations An N-R iterative root-finder for systems of N equations and N unknowns. Author: John Fuller	newton, raphson, iterative, solver, systems of equations, root	18	2	2.0 2.0 \| 1 rating

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25 Jan 2013		Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param. Author: John Fuller	aerospace, rotation, 3d, direction cosines, euler angle, dcm	105	32	4.58333 4.6 \| 12 ratings

Comments and Ratings Matching John's Watch List			1-5 of 38
Date	File	Comment by	Comments	Rating
29 Jan 2013	Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param.	Paolo de Leva	That's bad. My second last posting was totally deleted by MATLAB Central, possibly because it contained special characters... I wrote that in your latest release of SpinCalc, you introduced a new bug in line 238. In that line (which I cannot copy here because it contains special characters), you should use the element-by-element OR operator (single vertical bar), rather than the short-circuit OR operator (double bar) which does not work when N is greater than 1. In short, you should go back to previous version of line 238. Please also check my 4 advices posted yesterday.	Comment only
29 Jan 2013	Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param.	Paolo de Leva	MATLAB Central keeps truncating everything I write after special characters. In my latest posting, the logical OR operators and whatever was written after them were deleted. Anyway, you can check previous version of line 238. You should use the element-by-element OR operator (single vertical bar), rather than the short-circuit OR operator (double bar).	Comment only
28 Jan 2013	Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param.	Paolo de Leva	I have been trying to post this text, but MATLAB Central keeps truncating it. Here is the complete version, with special characters removed: 1) Please update the release version number. 2) Line 388: OUTPUT=mod([psi,theta,phi]180/pi,360); Proposed change: OUTPUT=[psi,theta,phi]180/pi; THETA is computed in your code either using ACOS or ASIN. In MATLAB, both ACOS(X) and ASIN(X) return values within a limited range. For -1 =< X =< 1, ACOS_X = ACOS(X)(180/pi) always returns values ranging from 0 to 180 degrees. This almost coincides with the range (from 0.1 to 179.9 degrees) accepted by SpinCalc as input for THETA (with EA type 2 rotations). Similarly, for -1 =< X =< 1, ASIN_X = ASIN(X)(180/pi) always returns angles ranging from -90 to 90 degrees. Again, this almost coincides with the range (from -89.9 to 89.9 degrees) accepted by SpinCalc as input for THETA (with EA type 1 rotations). If X < -1 or X > 1, then the result ACOS_X or ASIN_X is complex, and SpinCalc returns an error message. Computing MOD(ACOS_X,360) is useless, because THETA = MOD(ACOS_X, 360) = ACOS_X More importantly, computing MOD(ASIN_X,360) is inconsistent with other parts of your code, because for negative values of ASIN_X (i.e. -90 =< ASIN_X < 0 degrees) THETA = MOD(ASIN_X, 360) == ASIN_X + 360 which means that, for negative values of ASIN_X, THETA will range from 270 =< ASIN_X < 360 degrees, which is considered to be out range when used as input for SpinCalc (with EA type 1 rotations). 3) Line 396: sing_chk=... [find(abs(theta180/pi) < 0.1); ... find(abs(theta180/pi-180) < 0.1);... find(abs(theta180/pi-360)) < 0.1]; Proposed change: sing_chk=... [find(abs(theta180/pi) < 0.1); ... find(abs(theta180/pi-180) < 0.1);... find(abs(theta180/pi-360) < 0.1)]; 4) Every time you convert a Nx1 or Nx3 array containing angles in radians into an array containing angles in degrees, or vice versa (and you do it a lot of times in your code, including the above mentioned lines 388 and 396), you use this syntax: Y = X180/pi or Y = Xpi/180 This way, you repeat the division (by PI or by 180) N times. I suggest you to use this sintax, which is much more efficient as it computes the division only once (see also functions deg2rad and rad2deg): Y = X(180/pi) or Y = X(pi/180).	Comment only
28 Jan 2013	Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param.	Paolo de Leva	I am trying to post this text, containing a few notes about SpinCalc, but the web site keeps truncating it. Here is the complete version, with a few special characters removed: 1) Please update the release version number. 2) Line 388: OUTPUT=mod([psi,theta,phi]180/pi,360); Proposed change: OUTPUT=[psi,theta,phi]180/pi; THETA is computed in your code either using ACOS or ASIN. In MATLAB, both ACOS(X) and ASIN(X) return values within a limited range. For -1 <= X <= 1, ACOS_X = ACOS(X)(180/pi) always returns values ranging from 0 to 180 degrees. This almost coincides with the range (from 0.1 to 179.9 degrees) accepted by SpinCalc as input for THETA (with "input type" EA### and "Euler type" 2). Similarly, for -1 <= X <= 1, ASIN_X = ASIN(X)(180/pi) always returns angles ranging from -90 to 90 degrees. Again, this almost coincides with the range (from -89.9 to 89.9 degrees) accepted by SpinCalc as input for THETA (with "input type" EA### and "Euler type" 1). If X > 1 or X < -1, then the result ACOS_X or ASIN_X is complex, and SpinCalc returns an error message. Computing MOD(ACOS_X,360) is useless, because THETA = MOD(ACOS_X, 360) = ACOS_X More importantly, computing MOD(ASIN_X,360) is inconsistent with other parts of your code, because for negative values of ASIN_X (i.e. -90 <= ASIN_X < 0 degrees) THETA = MOD(ASIN_X, 360) == ASIN_X + 360 which means that, for negative values of ASIN_X, THETA will range from 270 <= ASIN_X < 360 degrees, which is considered to be out range when used as input for SpinCalc (with "input type" EA### and "Euler type" 1). 3) Line 396: sing_chk=... [find(abs(theta180/pi) < 0.1); ... find(abs(theta180/pi-180) < 0.1);... find(abs(theta180/pi-360)) < 0.1]; Proposed change: sing_chk=... [find(abs(theta180/pi) < 0.1); ... find(abs(theta180/pi-180) < 0.1);... find(abs(theta180/pi-360) < 0.1)]; 4) Every time you convert a Nx1 or Nx3 array containing angles in radians into an array containing angles in degrees, or vice versa (and you do it a lot of times in your code, including the above mentioned lines 388 and 396), you use this syntax: Y = X180/pi or Y = Xpi/180 This way, you repeat the division (by PI or by 180) N times. I suggest you to use this sintax, which is much more efficient as it computes the division only once (see also functions deg2rad and rad2deg): Y = X(180/pi) or Y = X(pi/180).	Comment only
28 Jan 2013	Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors Function to convert rotation data between 4 types: DCM, Euler Angles, Quaternions, and Euler Param.	Paolo de Leva	I am trying to post this text, containing a few notes about SpinCalc, but the web site keeps truncating it. Here is the complete version, with a few special characters removed: 1) Please update the release version number. 2) Line 388: OUTPUT=mod([psi,theta,phi]180/pi,360); Proposed change: OUTPUT=[psi,theta,phi]180/pi; THETA is computed in your code either using ACOS or ASIN. In MATLAB, both ACOS(X) and ASIN(X) return values within a limited range. For -1<=X<=1, ACOS_X = ACOS(X)(180/pi) always returns values ranging from 0 to 180 degrees. This almost coincides with the range (from 0.1 to 179.9 degrees) accepted by SpinCalc as input for THETA (with "input type" EA### and "Euler type" 2). Similarly, for -1<=X<=1, ASIN_X = ASIN(X)(180/pi) always returns angles ranging from -90 to 90 degrees. Again, this almost coincides with the range (from -89.9 to 89.9 degrees) accepted by SpinCalc as input for THETA (with "input type" EA### and "Euler type" 1). If X>1 or X<-1, then the result ACOS_X or ASIN_X is complex, and SpinCalc returns an error message. Computing MOD(ACOS_X,360) is useless, because THETA = MOD(ACOS_X, 360) = ACOS_X More importantly, computing MOD(ASIN_X,360) is inconsistent with other parts of your code, because for negative values of ASIN_X (i.e. -90<=ASIN_X<0 degrees) THETA = MOD(ASIN_X, 360) == ASIN_X + 360 which means that, for negative values of ASIN_X, THETA will range from 270<=ASIN_X<360 degrees, which is considered to be out range when used as input for SpinCalc (with "input type" EA### and "Euler type" 1). 3) Line 396: sing_chk=... [find(abs(theta180/pi)<0.1); ... find(abs(theta180/pi-180)<0.1);... find(abs(theta180/pi-360))<0.1]; Proposed change: sing_chk=... [find(abs(theta180/pi)<0.1); ... find(abs(theta180/pi-180)<0.1);... find(abs(theta180/pi-360)<0.1)]; 4) Every time you convert a Nx1 or Nx3 array containing angles in radians into an array containing angles in degrees, or vice versa (and you do it a lot of times in your code, including the above mentioned lines 388 and 396), you use this syntax: Y = X180/pi or Y = Xpi/180 This way, you repeat the division (by pi or by 180) N times. I suggest you to use this sintax, which is much more efficient as it computes the division only once: Y = X(180/pi) or Y = X(pi/180).	Comment only