Since much of what I post couldn't possibly be of interest to anyone else, I thought I'd use the blog. If I remember its existence, I'll try to post here stuff to myself. After all it's less likely to be lost here than in the maze of my harddrive.

Today I want to write about some Maple functions I've learned. I have just looked up the "events" option of dsolve. The description is pretty abstract and would have been nearly useless without some examples. Fortunately, I thought the examples were rather good. So I think I understand, in broad sweeps, what "events" does, and it's nice.

Today I also looked up map and map2. This in itself is an act of courage. map and map2 belongs to those Maple commands that I had until now shunted. Too scary. So I've read the help page, and I'm none the wiser. Just what I feared.

I tried these:
> map(f, x + y);

                             f(x) + f(y)

> map(f, y * z);

                              f(y) f(z)

> map(f, x + y * z);

                            f(x) + f(y z)

> map(f, y * z + x);

                            f(x) + f(y z)

> map(x -> exp(x), x + y);

                           exp(x) + exp(y)

> map(x -> exp(x), y * z);

                            exp(y) exp(z)

> map(x -> exp(x), x + y * z);

                          exp(x) + exp(y z)



I expected to get this:

>> map(f, y * z + x);

                            f(y) * f(z+x)

but obviously that's not the way map works. map gives addition some sort of priority over multiplication, I guess. I know, I know, it says here:

The map commands apply fcn to the operands or elements of expr.

what does that mean?

A blog is for questions to oneself like these, right?


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