Activity for Joseph Cusumano

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    OK, here's my example with your code. Do you see how has exactly the same structure? (%i4) node_1: V1/ro4 + gm4*V1 + (V1-V2)/ro6 + gm6*(Vin-V2) = 0$ node_2: (V2-V1)/ro6 + (V2-V3)/Rs - gm6*(Vin-V2) = 0$ node_3: (V3-V2)/Rs + V3/ro5 + gm5*V3 = 0$ output_node: Iout + gm3*V1 - gm5*V3 - V3/ro5 = 0$ Then this fails when you try what you did: (%i5) linsolve([node_1, node_2, node_3, output_node], [Iout,Vin]); (%o5) [] But you get an answer if you have four unknowns in linsolve. My guess is that Vin should...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    As I said, this is a general math issue. You have four equations. You need to have 4 unknowns for the problem to be well posed. Not 1, 2, 3. Not 5. You cannot uniquely solve for all of V1, V2, V3, Vin, Iout with only 4 equations! Pick four, including Vin and Iout. Then you can find the ratio. Do you not see the relevance of the example I posted?

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you should have four unknowns. You only have two unknowns in linsolve. An example from a simple worksheet: (%i4) e1:a*w+d*z=1$ e2:-a*x-c*y=2$ e3:c*y-c*z=-1$ e4:-a*x+c*y=10$ Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to play around with...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you should have four unknowns. You only have two unknowns in linsolve. An example from a simple worksheet: (%i1) e1:a*w+d*z=1$ (%i2) e2:-a*x-c*y=2$ (%i3) e3:c*y-c*z=-1$ (%i4) e4:-a*x+c*y=10$ Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you can s nowns. You only have two unknowns in linsolve. An example from a simple worksheet: (%i1) e1:a*w+d*z=1$ (%i2) e2:-a*x-c*y=2$ (%i3) e3:c*y-c*z=-1$ (%i4) e4:-a*x+c*y=10$ Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to play around with...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you can s nowns. You only have two unknowns in linsolve. An example from a simple worksheet: (%i4) e1:a*w+d*z=1; e2:-a*x-c*y=2; e3:c*y-c*z=-1; e4:-a*x+c*y=10; Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to play around with your problem in...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you can s nowns. You only have two unknowns in linsolve. An example from a simple worksheet: (%i4) e1:a*w+d*z=1; e2:-a*x-c*y=2; e3:c*y-c*z=-1; e4:-a*x+c*y=10; Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to play around with your problem in...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you can s nowns. You only have two unknowns in linsolve. An example from a simple worksheet: (%i4) e1:a*w+d*z=1; e2:-a*x-c*y=2; e3:c*y-c*z=-1; e4:-a*x+c*y=10; Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to play around with your problem in...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you can s nowns. You only have two unknowns in linsolve. An example from a simple worksheet: e1:a*w+d*z=1; e2:-a*x-c*y=2; e3:c*y-d*z=-1; e4:-a*x+c*y=10; Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to play around with your problem in wxMaxima,...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you can s nowns. You only have two unknowns in linsolve. a simple worksheet: e1:a*w+d*z=1; e2:-a*x-c*y=2; e3:c*y-d*z=-1; e4:-a*x+c*y=10; Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to play around with your problem in wxMaxima, they can without...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you can s nowns. You only have two unknowns in linsolve. a simple worksheet: (%i4) e1:a*w+d*z=1; e2:-a*x-c*y=2; e3:c*y-d*z=-1; e4:-a*x+c*y=10; Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to play around with your problem in wxMaxima, they...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you can solve for four unknowns. You only have two unknowns in linsolve. An example from a simple worksheet: e1:a*w+d*z=1; e2:-a*x-c*y=2; e3:c*y-d*z=-1; e4:-a*x+c*y=10; Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to play around with your...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you can solve for four unknowns. You only have two unknowns in linsolve. An example from a simple worksheet: (%i4) e1:a*w+d*z=1; e2:-a*x-c*y=2; e3:c*y-d*z=-1; e4:-a*x+c*y=10; Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to play around with...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you can solve for four unknowns. You only have two unknowns in linsolve. An example from a simple worksheet: (%i4) e1:a*w+d*z=1; e2:-a*x-c*y=2; e3:c*y-d*z=-1; e4:-a*x+c*y=10; Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to play around with...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    This is a math problem, not a maxima problem. You have four equations, so you can solve for four unknowns. You only have two unknowns in linsolve. An example from a simple worksheet: (%i4) e1:a*w+d*z=1; e2:-a*x-c*y=2; e3:c*y-d*z=-1; e4:-a*x+c*y=10; Then: (%i5) linsolve([e1,e2,e3,e4],[w,x]); (%o5) [] But: (%i6) linsolve([e1,e2,e3,e4],[w,x,y,z]); (%o6) [w=-4/a,x=-6/a,y=4/c,z=5/d] Suggestion: it's better to post your code, when possible, not a screenshot. That way if someone wants to play around with...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    I have the same problem with both 17.05.1 and 17.10.1, both compiled under Linux Mint 17.3. This happens the very first time I search in the Index tab of help. If I click the "Stop" button, it crashes wxMaxima. If I press the "Continue" button the program continues normally until the next Index search. If in addition I uncheck "Show this dialogue the next time", the program continues without any more notifications for the remainder of the session. There are no assertion failures in the the Contents...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    What you're expecting isn't correct. a/abs(a) is plus or minus 1, if a is real. If a is complex, it is a/sqrt(a*conjugate(a)). You're forgetting that a can be any kind of number, as far as Maxima is concerned. You have know what you are trying to do to get Maxima to do it. If you know that a is real and positive, then use assume(a>0).

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    You want to make the first argument to makelist a bit more complicated, like this: N:10$ /* one less than the number of steps you want */ makelist(float(-10+k*20/N),k,0,N);

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    I just told you how to do it.

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    This is not correct: the del's indicate differentials, not partial derivatives. Also, the arithmetic operators are not correct in the given expression. Make sure to include * every time two numbers or symbols are multiplied. Do it like this: /* define the function */ f:z^3-3*x^2*y+6*x*y*z; /* total differential of f: coefficients of del's are partial derivatives */ diff(f); /* another way to do the same thing as above */ del(f); ev(%,eval,diff); /* partials of f with respect to x, y, and z, respectively...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    This is not correct: the del's indicate differentials, not partial derivatives. Also, the arithmetic operators are not correct in the given expression. Make sure to include * every time two numbers or symbols are multiplied. Do it like this: /* define the function */ f:z^3-3*x^2*y+6*x*y*z; /* total differential of f: coefficients of del's are partial derivatives */ diff(f); /* another way to do the same thing as above */ del(f); ev(%,eval,diff); /* partials of f with respect to x, y, and z, respectively...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    Unfortunately, 16.12.2 caused a weird problem with my graphics: on Linux Mint 17.3...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    I'm using wxMaxima built from git source, and floating point numbers all have [x...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    You have to be more careful. You lost the division operator in your definion of z....

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    This does it: solve('z=z,w)[1]; subst(%,x); expand(factor(%));

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    Maxima has contour_plot, but it's hard to control the level sets you're using. A...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    Maxima has contour_plot, but it's hard to control the level sets you're using. A...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    Maxima hascontour_plot, but it's hard to control the level sets you're using. A more...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    Once you assign something to a symbol, it is always evaluated. So, for example a:wt...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    This is a known problem with the maxima package that's in the Ubuntu 16.04 repositories....

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    I'm having the same problem with both the latest binaries from Blahota (wxMaxima...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    I'm having the same problem with both the latest binaries from Blahota (wxMaxima...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    I'm seeing exactly the same behavior as Christopher, with the latest version just...

  • Joseph Cusumano Joseph Cusumano modified a comment on discussion Open Discussion

    Thanks, Kenneth, for checking that on a Mint machine. You are indeed right--I was...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    Thanks, Kenneth, for checking that on a Mint machine. You are indeed right--I was...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    Hi Kenneth. Thanks for your reply. This is my stable, solid work computer, and I...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    I'm using wxMaxima 14.12.1 under Linux Mint 17.3. The print function is not working....

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    Chris W wrote the following on 5/6/2014 4:42 PM: I've got two functions f(x) and...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    Wolfgang Meiners wrote the following on 3/31/2014 5:40 PM: kill(all); CP(a,b):= [a[2]b[3]-a[3]b[2],...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    Your function works fine on my system: (%i1) CP(a,b):= [a[2]*b[3]-a[3]*b[2], a[3]*b[1]-a[1]*b[3],...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    Here's a hack that does what you want. It requires that the argument to the function...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    daviodan daviodan wrote the following on 3/11/2014 8:56 AM: http://sourceforge.net/p/wxmaxima/discussion/435775/thread/f2340d15/#b66b/7451...

  • Joseph Cusumano Joseph Cusumano posted a comment on discussion Open Discussion

    float(sin(%pi/12)); goin' mobile On Mar 10, 2014, at 11:59 AM, "daviodan daviodan"...

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