Math software comparison

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Differentiation

I was searching half an hour for higher order derivatives in Mathematica but found nothing. Another half an hour spent in learning to take first order derivative. It works.
In Matlab commands syms x, f=cos(x)^sin(x), diff(f,x,5) produced the result. The command diff(f,x,50) put my computer into long sleep. The Windows Task Manager showed 100% of CPU usage. Waiting...waiting...drinking tea... . I know this derivative is very long. Terminating Matlab, starting again with command diff(f,x,10). Again long calculation, 100% CPU load, but no Matlab massage, just cursor blinking. In meanwhile I had started my Derivative Calculator Level 1 and got answer in about a minute. Pretty long string. In about twenty minute Matlab gave answer. Trying to compare it with my result, I had copied and pasted the answer string from Matlab to WordPad. For my surprise, the answer string had at the end message: 'Output truncated. Text exceeds maximum line length of 25,000 characters for Command Window display'.
I had started Maple 13. Usage of formula diff(cos(x)^sin(x),x) gave right answer. Usage of diff(cos(x)^sin(x),x,5) gave an error message. Googling. The command diff(cos(x)^sin(x),x$5) gave result. The command diff(cos(x)^sin(x),x$10) gave surprisingly quick answer. Selection by hand so long string was not easy. Right-click menu had Evaluation at point. Nice. The command diff(cos(x)^sin(x),x$20) gave quick answer. Wow. My respect. Evaluating at point. Oops, mouse selection does not work. Cursor selection works painfully slow. I was unable to select the end of result string. After some random clicking I finally got the string selected and evaluated. It seems that Maples is not ready to work with big strings. The command diff(cos(x)^sin(x),x$30) terminated quickly with message 'the string exceeds 1,000,000 length'. The command diff(cos(x)^sin(x),x$25) entered a long loop with CPU load about 50%. After 20 min the CPU load fell to zero but no answer appeared in Maple. Just blinking cursor. Nevertheless the result diff(cos(x)^sin(x)x$20) is impressive. I shall reconsider my open brackets approach.
So, the winner in differentiation contest is Maple.

Further experimenting with Maple 13 revealed that the restriction of Maple in working strings length is essential. For example, if for sin(x)^cos(x) Maple was able to compute about 25th derivative, then for cos(sin(x)^cos(x)) only 18th derivative. The more complex starting function, the less maximal order of derivative.