| Author |
 Topic  |
|
|
DataConv
Germany
60 Posts |
 Posted - 10/29/2013 : 05:53:21 AM
|
Origin Ver. and Service Release (Select Help-->About Origin): 9.0.0G Pro SR2
Operating System: W7 Pro SP1
The Amplitude/Phase to complex matrix XFunction (map2c) has the option to switch between radians and degree. The radian option works fine for me, the degree option not. Weird complex data are the result. Not only the resulting amplitude magnitude is altered, but also the angle is wrong... Currently i do a manual degree to radians conversion of the phase, and then an undo to source phase matrix - but that eats up time and is a bad workaround...
Can this behaviour be confirmed?
PS: the help annoyes me often: if an option is given and it is written that the possible arguments are e.g. 'radians','degree' it often does not work directly (e.g. 'arc:=degree') and it has to be substituted by a number 'arc:=1'. PLEASE MARK THAT FOR THE ARGUMENT (like 0: Radians, 1: Degree). Sometimes it is a trial and error game to find out which number does what... |
|
|
greg
USA
1379 Posts |
Posted - 10/30/2013 : 12:27:41 PM
|
I think I see a problem, but I will have to check with the programmers.
If I do a 2D FFT on a matrix and generate Amplitude, Phase and Complex results, I can use the Amplitude and Phase results along with the map2c X-Function and generate a Complex result (using radians option) that is identical to the Complex result of the original 2D FFT.
I can also use map2c with the degree option to generate a Complex matrix.
Using the DC point of the complex result using radians:
5150.4027
I found that the DC point of the complex result using radians could be computed by:
pi * 5150.4027 / 180 = 89.89148
but that seems backwards because I used the formula to convert from degrees to radians, not radians to degrees.
While that conversion was accurate (assuming we have our options backward) a conversion of an arbitrary point in the matrix did not go well:
pi * ( -550.38694 + 498.17684i ) / 180 =
-9.6060642629765 + 8.694826115181i
whereas the value found in the matrix was:
12.94529 + 0.54391i
Stay tuned to see what the programmers reply... |
 |
|
|
minimax
357 Posts |
Posted - 11/04/2013 : 02:55:10 AM
|
Hi Jrgen,
We did find the unit option was not correctly used in the map2c tool and the fix should be available in the next release (probably 9.1 sr1).
As to the problem on using "arc:=degree", we cannot reproduce it yet.
In general, both "arc:=degree" and "arc:=1" should work the same and compute a same result (regardless of whether the result is correct or not).
Therefore, Would you mind to show us more details (like some data and script) to indicate that "arc:=degree" did not get a same result as "arc:=1"?
|
|
|
| |
Topic |
|
|
|
Bug in the map2c XFunction?