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Almanac
Almanac gives you the capability to determine the times of rising, setting, and meridian transit for the sun, the moon, and the planets. It also enables you to calculate the beginning and ending of astronomical, nautical, and civil twilight. The results of the calculations are formatted and written into a text editor. You can perform all common editing functions and save the data as a text file.
The formulae used in Almanac assume an ideal horizon where the intersection of the sky with the apparent plane of the earth's surface at the observer is the horizon. For rise/set calculations, the observer has zero elevation so that the horizon is exactly 90 degrees from the local vertical. Refraction of light passing through the earth's atmosphere tends to make objects appear higher in the sky than they actually are. This effect increases as an object's altitude decreases. Almanac assumes average atmospheric conditions in compensating for refraction. Lunar parallax changes the perceived altitude of the moon because the observer is not at the center of the earth. Parallax makes that the moon appears lower in the sky. Almanac compensates for this effect. Parallax for the Sun and planets is small enought to be ignored for this application.
Keywords: sun moon planets rise transit set twilight calculates times rise set transit sun moon planets icsa
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C++ sets class
The sets class can be used to perform set operations in your programs. It represents set elements as bits in a private array of unsigned long integers. The array size is a defined constant which can be changed to suit your application. The sets class supports the following set operations by means of C++ operator overloading: union The union of two sets A, B is the set of all elements which belong to either A or B. In the sets class, the symbol + is the binary union operator: A + B = {x: x is in A -or- x is in B } intersection The intersection of two sets A, B is the set of all elements which belong to both A and B. The symbol * is the binary intersection operator: A * B = {x: x is in A -and- x is in B } example Let A = {1, 2, 3, 4} and B = {3, 4, 5, 6}. Then A + B = {1, 2, 3, 4, 5, 6} A * B = {3, 4} complement In set theory, sets are subsets of a fixed universal set U. In the sets class, U is the set of elements numbered from 1 to MAX_WORDS * WORD_SIZE. In the class declaration file below, the following definitions are made: #define MAX_WORDS 2 #define WORD_SIZE ( 8 * sizeof( unsigned long ) ) These parameters make the range of U, 1 to 64 in sets. To increase or decrease the size of U, change the defined value of MAX_WORDS. The complement of set A is the set of elements belonging to U but not belonging to A. The symbol ~ is the unary complement operator: ~A = {x: x is in U, x is not in A } example Let A = {1, 2, 3, 4} and B = {3, 4, 5, 6}. Then ~A = {5, 6, 7, . . .} ~B = {1, 2, 7, 8, 9, . . .} difference The difference of two sets A, B is the set of all elements which belong to A less those in B. The symbol - is the binary difference operator: A - B = {x: x is in A, x is not in B} example Let A = {1, 2, 3, 4} and B = {3, 4, 5, 6}. Then A - B = {1, 2} It can be shown that A - B = A * ~B. symmetric difference The symmetric difference of two sets A, B is the set of all elements which belong to A or to B, but not both.
Keywords: sets class c/c++ answer back
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