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If you have a list of numbers v = {3, 9/2, 4} the command GCD will not work on a list and returns {3, 9/2, 4} but GCD[3, 9/2, 4] returns an answer of 1/2 which is correct. How do you 'unlist' a list so that GCD will work...
The attached notebook shows a small problem with exponent to trig form. I have a simple expression like this: In[32]:= a = Exp[(5 I \[Pi])/12] Out[32]= E^((5 I \[Pi])/12) If you try to convert this to trig form you get: ...
I need to generate a pulse train where the time duration of the pulse td
In the following program, I want to generate four graphs by iterating the variable n and plotting the results as a 2 X 2 grid. The iterator does not seem to be working as expected even though it is in the correct format {n, nmin, nmax, dn}. The...
Sometimes when plotting functions, you want to do some operation on the y-axis. This comes up when you want to plot say decibels vs. frequency. It is not clear how you can do an operation like performing 10 Log10 on the y-axis values. Is there a...
I want to turn expression a+b+c+d into list {a,b,c,d}. I always thought there was a command to do this. Any thoughts on a simple way to do this?
While the expressions 1/z^2 and z^-2 are equivalent, in many signal processing applications the z^-2 form is more useful. However Mathematica will usually express the form as 1/z^2. Is there a way to force Mathematica to display the alternative...
If you have a difference equation like this: eqn = y[n + 2] - 5 y[n + 1] + 6 y[n] == 3 (0.5)^(1 + n) UnitStep[1 + n] + 5 (0.5)^n UnitStep[n] 6 y[n] - 5 y[1 + n] + y[2 + n] == 5 0.5^n UnitStep[n] + 3 0.5^(1 +...