54 lines
1.9 KiB
Plaintext
54 lines
1.9 KiB
Plaintext
Calc is an interactive calculator which provides for easy large
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numeric calculations, but which also can be easily programmed for
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difficult or long calculations. It can accept a command line
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argument, in which case it executes that single command and exits.
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Otherwise, it enters interactive mode. In this mode, it accepts
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commands one at a time, processes them, and displays the answers. In
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the simplest case, commands are simply expressions which are
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evaluated. For example, the following line can be input:
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3 * (4 + 1)
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and the calculator will print 15.
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The special '.' symbol (called dot), represents the result of the last
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command expression, if any. This is of great use when a series of
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partial results are calculated, or when the output mode is changed and
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the last result needs to be redisplayed. For example, the above
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result can be doubled by typing:
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. * 2
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and the calculator will print 30.
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For more complex calculations, variables can be used to save the
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intermediate results. For example, the result of adding 7 to the
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previous result can be saved by typing:
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old = . + 7
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Functions can be used in expressions. There are a great number of
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pre-defined functions. For example, the following will calculate the
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factorial of the value of 'old':
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fact(old)
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and the calculator prints 13763753091226345046315979581580902400000000.
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Notice that numbers can be very large. (There is a practical limit
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of several thousand digits before calculations become too slow.)
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The calculator can calculate transcendental functions, and accept and
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display numbers in real or exponential format. For example, typing:
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config("display", 50)
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epsilon(1e-50)
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sin(1)
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prints "~.84147098480789650665250232163029899962256306079837".
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The calculator also knows about complex numbers, so that typing:
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(2+3i) * (4-3i)
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prints "17+6i".
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