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Sage拥有强大的内置文档,只需要输入函数或者常数的名字,再加个问号即可：

  1. sage: tan?
  2. Type:   <class 'sage.calculus.calculus.Function_tan'>
  3. Definition: tan([noargspec])
  4. Docstring:
  6.     The tangent function
  8.         EXAMPLES:
  9.         sage: tan(pi)
  10.         0
  11.         sage: tan(3.1415)
  12.         -0.0000926535900581913
  13.         sage: tan(3.1415/4)
  14.         0.999953674278156
  15.         sage: tan(pi/4)
  16.         1
  17.         sage: tan(1/2)
  18.         tan(1/2)
  19.         sage: RR(tan(1/2))
  20.         0.546302489843790
  21. sage: log2?
  22. Type:   <class 'sage.functions.constants.Log2'>
  23. Definition: log2([noargspec])
  24. Docstring:
  26.     The natural logarithm of the real number 2.
  28.         EXAMPLES:
  29.         sage: log2
  30.         log2
  31.         sage: float(log2)
  32.         0.69314718055994529
  33.         sage: RR(log2)
  34.         0.693147180559945
  35.         sage: R = RealField(200); R
  36.         Real Field with 200 bits of precision
  37.         sage: R(log2)
  38.         0.69314718055994530941723212145817656807550013436025525412068
  39.         sage: l = (1-log2)/(1+log2); l
  40.         (1 - log(2))/(log(2) + 1)
  41.         sage: R(l)
  42.         0.18123221829928249948761381864650311423330609774776013488056
  43.         sage: maxima(log2)
  44.         log(2)
  45.         sage: maxima(log2).float()
  46.         .6931471805599453
  47.         sage: gp(log2)
  48.         0.6931471805599453094172321215 # 32-bit
  49.         0.69314718055994530941723212145817656807 # 64-bit
  50. sage: sudoku?
  51. File:   sage/local/lib/python2.5/site-packages/sage/games/sudoku.py
  52. Type:   <... 'function'>
  53. Definition: sudoku(A)
  54. Docstring:
  56.     Solve the 9x9 Sudoku puzzle defined by the matrix A.
  58.         EXAMPLE:
  59.             sage: A = matrix(ZZ,9,[5,0,0, 0,8,0, 0,4,9, 0,0,0, 5,0,0,
  60.             0,3,0, 0,6,7, 3,0,0, 0,0,1, 1,5,0, 0,0,0, 0,0,0, 0,0,0, 2,0,8, 0,0,0,
  61.             0,0,0, 0,0,0, 0,1,8, 7,0,0, 0,0,4, 1,5,0, 0,3,0, 0,0,2,
  62.             0,0,0, 4,9,0, 0,5,0, 0,0,3])
  63.             sage: A
  64.            [5 0 0 0 8 0 0 4 9]
  65.            [0 0 0 5 0 0 0 3 0]
  66.            [0 6 7 3 0 0 0 0 1]
  67.            [1 5 0 0 0 0 0 0 0]
  68.            [0 0 0 2 0 8 0 0 0]
  69.            [0 0 0 0 0 0 0 1 8]
  70.            [7 0 0 0 0 4 1 5 0]
  71.            [0 3 0 0 0 2 0 0 0]
  72.            [4 9 0 0 5 0 0 0 3]
  73.             sage: sudoku(A)
  74.            [5 1 3 6 8 7 2 4 9]
  75.            [8 4 9 5 2 1 6 3 7]
  76.            [2 6 7 3 4 9 5 8 1]
  77.            [1 5 8 4 6 3 9 7 2]
  78.            [9 7 4 2 1 8 3 6 5]
  79.            [3 2 6 7 9 5 4 1 8]
  80.            [7 8 2 9 3 4 1 5 6]
  81.            [6 3 5 1 7 2 8 9 4]
  82.            [4 9 1 8 5 6 7 2 3]

Sage还提供了”Tab补全”功能：输入函数名的前面几个字母,然后按tab键。比如,如果你输入ta再按TAB,Sage就会列出tachyon, tan, tanh, taylor. 这是一个查找Sage函数或者其他结构的好方法。