You can type the function only once with the expression_plot option, and the help page has the following example for that,

plotcompare(BesselK(1/2,z), expression_plot, 3);

In this case, only 2 plots are displayed (for Re and for Im) instead of 4.

Alec

You can type the function only once with the expression_plot option, and the help page has the following example for that,

plotcompare(BesselK(1/2,z), expression_plot, 3);

In this case, only 2 plots are displayed (for Re and for Im) instead of 4.

Alec

Well, the probability distribution is certainly of mixed type, but that doesn't mean that it doesn't have a PDF. The term is widely used, even for discrete probability distributions, especially in Russian literature, in which distributions (like the Dirac function) are also called generalized functions.

How else it can be called? I've never heard about PDDs (probability density distributions).

Maple also uses this term for discrete probability distributions. For example,

with(Statistics):

PDF(Bernoulli(1/2),t);

                   1/2 Dirac(t) + 1/2 Dirac(t - 1)

PDF(Binomial(n,p),t);

       infinity
        -----
         \                      k         (n - k)
          )     binomial(n, k) p  (-p + 1)        Dirac(t - k)
         /
        -----
        k = 0

Both are not functions.

Some confusion may be caused by 2 different meanings of the word "distribution" - a probability distribution, which is one thing, and a functional on a function space (like the Dirac function), which is something completely different.

Alec

Well, the probability distribution is certainly of mixed type, but that doesn't mean that it doesn't have a PDF. The term is widely used, even for discrete probability distributions, especially in Russian literature, in which distributions (like the Dirac function) are also called generalized functions.

How else it can be called? I've never heard about PDDs (probability density distributions).

Maple also uses this term for discrete probability distributions. For example,

with(Statistics):

PDF(Bernoulli(1/2),t);

                   1/2 Dirac(t) + 1/2 Dirac(t - 1)

PDF(Binomial(n,p),t);

       infinity
        -----
         \                      k         (n - k)
          )     binomial(n, k) p  (-p + 1)        Dirac(t - k)
         /
        -----
        k = 0

Both are not functions.

Some confusion may be caused by 2 different meanings of the word "distribution" - a probability distribution, which is one thing, and a functional on a function space (like the Dirac function), which is something completely different.

Alec

The PDF can be found as

diff(convert(f,Heaviside),x);

But if you try to plot it, the plot will be wrong at x=-10. It can be visualized as being infinity at x=-10, but it is also not exactly right, because the distributions (like the Dirac functions) are not functions.

Alec

The PDF can be found as

diff(convert(f,Heaviside),x);

But if you try to plot it, the plot will be wrong at x=-10. It can be visualized as being infinity at x=-10, but it is also not exactly right, because the distributions (like the Dirac functions) are not functions.

Alec

f:=piecewise(x<-10,0,Statistics:-CDF(Normal(0,10),x));

plot(f,x=-20..40);

Alec

f:=piecewise(x<-10,0,Statistics:-CDF(Normal(0,10),x));

plot(f,x=-20..40);

Alec

CDF is more simple - it is the usual CDF for x ≥ -10 and 0 for x < -10. It can be easily plotted.

Alec

CDF is more simple - it is the usual CDF for x ≥ -10 and 0 for x < -10. It can be easily plotted.

Alec

You can't plot a Dirac function (because it is not a function actually.)

Alec

You can't plot a Dirac function (because it is not a function actually.)

Alec

fsolve instead of solve, with specifying a positive range for N works,

plot('fsolve'(Ep-E,N=0..20),Z=0..20);

Alec

fsolve instead of solve, with specifying a positive range for N works,

plot('fsolve'(Ep-E,N=0..20),Z=0..20);

Alec

Yes, I left a message there, too.

The disadvantage of using that is that I don't get any feedback. I filled probably 5-10 such forms during past few months. Nothing has changed - all the mentioned problems are still there.

Normally (I mean on a normal sites, not here) I would get at least an email with a confirmation and a copy of my message.

Alec