gjm's profile - activity

I actually want to output just the x and y axis data. The provided link does not appear to provide me with this function.

Here is my code that graphs a function:

z1=2*pi*650*10^6

p1=2*pi*1.95*10^9

p2=2*pi*5*10^9

adc=.667

deltaF=.1*10^9

N=(adc*p1*p2)/z1

M(freq)=(2*i*pi*freq+z1)/((2*i*pi*freq+p1)*(2*i*pi*freq+p2))

Z=abs(N*M(freq))

g(freq)=20*log(Z,10)

pts=[(freq,g(freq).n()) for freq in srange(10^8,10^11,deltaF)]

list_plot(pts, plotjoined=True, scale='semilogx', gridlines="minor", ymin=-25, ymax=5)

How do I output this data to a file so I can compare it to data generated by another piece of software?

I am using Windows 7 and when I update SageMath I usually delete the old version (and the disk) and then update to the new .ova version. How do I save my worksheets or move them over?

list_plot(pts, scale='semilogx',plotjoined=True,ymin=2,ymax=20,gridlines=[[10^9,10^10],[5,10,15]])

I have a plot which sweeps over a range shown below and the plots it on a log scale on the horizontal axis (I am using 5.2 so the log scale feature is present).

1. However, rather than points, I would like to see a solid line and,
2. Some grid lines on both the horizontal and vertical axis at the tick points.
3. Is there also a way to control the range on the vertical axis?

Here is the entire formulation. The range on the y-axis I would like to see labeled is from -5 to -25. I asked a question before using the formulation below but the scale did not was off due to the wrong operator being used so I did not ask that particular question at the time:

z1=2 * pi * 650 * 10^6

p1=2 * pi * 1.9 * 10^9

p2=2 * pi * 5 * 10^9

adc=.667

deltaF=.2 * 10^9

N=(adc * p1 * p2)/z1

M(freq)=(-2 * i * pi * freq + z1)/((-2 * i * pi * freq+p1) * (-2 * i * pi * freq+p2))

g(frq)=20 * abs(log(N * M(frq),10))

pts=[(frq,g(frq).n()) for frq in srange(10^8,10^11,deltaF)]

list_plot(pts, scale='semilogx')

The sage-5.2.ova is the full Sage-5.2 install. The notebook in that version has a bug and passwordless login doesn't work (which is why you are probably staring at a black screen when you run it). The somewhat arcane instructions below should get you going. But since we want the virtual machine to be easy to use we are currently distributing the old version until that bug is fixed.

The notebook now asks for a admin password at the first boot. So to use this version of the VM, you need to

1. import appliance and boot as usual,

2. Simultaneously press Right-Ctrl F8

3. Enter the admin password on the console running the notebook server

4. Press Right-Ctrl F2 to get back to the browser showing the notebook.

Got it, it works great.

At what time do is press Right-Ctrl F8? Same question with Right-Ctrl F2. Thanks!

I just used 5.1 with Oracle VM and it works fine. The 5.2 ova file does not work. I got the 5.2 file from here: http://www.stp.dias.ie/~vbraun/Sage/s...

I was unable to fine the 5.2 .ova from the main page and navigate to it. The above link was provided to me in the answers.

Any help would be greatly appreciated. Am I using a beta version of 5.2? I need the log scale feature of 5.2.

I am using sage 5.2 with Oracle VM 4.1.18 and I just get a black screen. What are the possible causes of this?

I'm not getting the vertical range that you are specifying, but here is what I've got. Note that the log plot only works in the latest release (5.2) of Sage.

z1=2 * pi * 650 * 10^6
p1=2 * pi * 1.9 * 10^9
p2=2 * pi * 5 * 10^9
adc=.667
deltaF=.2 * 10^9

N=(adc * p1 * p2)/z1
M(freq)=(-2 * i * pi * freq * z1)/((-2 * i * pi * freq+p1) * (-2 * i * pi * freq+p2))

g(frq)=20*abs(log(N*M(frq),10))

pts=[(frq,g(frq).n()) for frq in srange(10^8,10^11,deltaF)]

list_plot(pts, scale='semilogx')

I need the log scale features in 5.2, but whenever I select the link for 5.2 virtualbox appliance it takes me to a page with the .ova file listed as 5.1.

It's okay, I got it to work with the abs defined where I wanted it and had one minor change to the equation to get the correct range. Now I need to find out how to get Sage 5.2.

Thanks for the answer. I actually needed to have the absolute value of N x M(freq) and that should give me the right range.

What is the correct syntax? I have tried log(abs(N x M(freq)),10)) and that does not seem to work and I get an error.

Also, is there a reason for the change from freq to frq? Thanks!

In the following x means multiply.

Let

z1=2 x pi x 650 x 10^6
p1=2 x pi x 1.9 x 10^9
p2=2 x pi x 5 x 10^9
adc=.667
deltaF=.2 x 10^9

In the following j is the imaginary representation Now let N=(adc x p1 x p2)/z1 and

M=(-2 x j x pi x freq x z1)/((-2 x j x pi x freq+p1) x (-2 x j x pi x freq+p2))

The base formula is abs(20 x log(N x M,10)) or the absolute value of 20 log(N x M) where the log base is base 10. Within the base formula is freq (the value of the frequency) which will be swept from 10^8 to 10^11 in steps of deltaF (.2 x 10^9)

The vertical range is from -25 to 5 (linear scale) and the horizontal range is from 10^8 to 10^11 (log scale)

The horizontal axis as stated is a Log scale as opposed to Linear.

How do I set this up in Sage to plot per the above? Thanks.

well this did not show up right. The first dotted line should separate adc omP1 omP2 which is the numerator and omZ1 which is the denominator and the second dotted line should separate (-I 2 Pi + omZ1) which is the numerator and then (-I 2 Pi + omP1)(-I 2 Pi + omP2) which is the denominator.

I want to take:

(adc*omP1*omP2)/omZ1)*(-I*2*Pi+ 
omZ1)/((-I*2*Pi + omP1)*(-I*2*Pi + omP2))

and have it shown as:

adc omP1 omP2     *     (-I 2 Pi + omZ1)
-------------            --------------
     omZ1        (-I 2 Pi + omP1)(-I 2 Pi + omP2)

The * between, for example, -I and 2 or 2 and Pi can be present, but I would like to see the equation in a more simplified form like the second case. I would even like to enter it in this way or at least have a way to convert.