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oasis-root

Compiled tree of Oasis Linux based on own branch at <https://hacktivis.me/git/oasis/> git clone https://anongit.hacktivis.me/git/oasis-root.git

j0.3p (3270B)

    

  1. '\" et
  2. .TH J0 "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual"
  3. .\"
  4. .SH PROLOG
  5. This manual page is part of the POSIX Programmer's Manual.
  6. The Linux implementation of this interface may differ (consult
  7. the corresponding Linux manual page for details of Linux behavior),
  8. or the interface may not be implemented on Linux.
  9. .\"
  10. .SH NAME
  11. j0,
  12. j1,
  13. jn
  14. \(em Bessel functions of the first kind
  15. .SH SYNOPSIS
  16. .LP
  17. .nf
  18. #include <math.h>
  19. .P
  20. double j0(double \fIx\fP);
  21. double j1(double \fIx\fP);
  22. double jn(int \fIn\fP, double \fIx\fP);
  23. .fi
  24. .SH DESCRIPTION
  25. The
  26. \fIj0\fR(),
  27. \fIj1\fR(),
  28. and
  29. \fIjn\fR()
  30. functions shall compute Bessel functions of
  31. .IR x
  32. of the first kind of orders 0, 1, and
  33. .IR n ,
  34. respectively.
  35. .P
  36. An application wishing to check for error situations should set
  37. .IR errno
  38. to zero and call
  39. .IR feclearexcept (FE_ALL_EXCEPT)
  40. before calling these functions. On return, if
  41. .IR errno
  42. is non-zero or \fIfetestexcept\fR(FE_INVALID | FE_DIVBYZERO |
  43. FE_OVERFLOW | FE_UNDERFLOW) is non-zero, an error has occurred.
  44. .SH "RETURN VALUE"
  45. Upon successful completion, these functions shall return the relevant
  46. Bessel value of
  47. .IR x
  48. of the first kind.
  49. .P
  50. If the
  51. .IR x
  52. argument is too large in magnitude, or the correct result would cause
  53. underflow, 0 shall be returned and a range error may occur.
  54. .P
  55. If
  56. .IR x
  57. is NaN, a NaN shall be returned.
  58. .SH ERRORS
  59. These functions may fail if:
  60. .IP "Range\ Error" 12
  61. The value of
  62. .IR x
  63. was too large in magnitude, or an underflow occurred.
  64. .RS 12 
  65. .P
  66. If the integer expression (\fImath_errhandling\fR & MATH_ERRNO) is
  67. non-zero, then
  68. .IR errno
  69. shall be set to
  70. .BR [ERANGE] .
  71. If the integer expression (\fImath_errhandling\fR & MATH_ERREXCEPT) is
  72. non-zero, then the underflow floating-point exception shall be raised.
  73. .RE
  74. .P
  75. No other errors shall occur.
  76. .LP
  77. .IR "The following sections are informative."
  78. .SH EXAMPLES
  79. None.
  80. .SH "APPLICATION USAGE"
  81. On error, the expressions (\fImath_errhandling\fR & MATH_ERRNO) and
  82. (\fImath_errhandling\fR & MATH_ERREXCEPT) are independent of each
  83. other, but at least one of them must be non-zero.
  84. .SH RATIONALE
  85. None.
  86. .SH "FUTURE DIRECTIONS"
  87. None.
  88. .SH "SEE ALSO"
  89. .IR "\fIfeclearexcept\fR\^(\|)",
  90. .IR "\fIfetestexcept\fR\^(\|)",
  91. .IR "\fIisnan\fR\^(\|)",
  92. .IR "\fIy0\fR\^(\|)"
  93. .P
  94. The Base Definitions volume of POSIX.1\(hy2017,
  95. .IR "Section 4.20" ", " "Treatment of Error Conditions for Mathematical Functions",
  96. .IR "\fB<math.h>\fP"
  97. .\"
  98. .SH COPYRIGHT
  99. Portions of this text are reprinted and reproduced in electronic form
  100. from IEEE Std 1003.1-2017, Standard for Information Technology
  101. -- Portable Operating System Interface (POSIX), The Open Group Base
  102. Specifications Issue 7, 2018 Edition,
  103. Copyright (C) 2018 by the Institute of
  104. Electrical and Electronics Engineers, Inc and The Open Group.
  105. In the event of any discrepancy between this version and the original IEEE and
  106. The Open Group Standard, the original IEEE and The Open Group Standard
  107. is the referee document. The original Standard can be obtained online at
  108. http://www.opengroup.org/unix/online.html .
  109. .PP
  110. Any typographical or formatting errors that appear
  111. in this page are most likely
  112. to have been introduced during the conversion of the source files to
  113. man page format. To report such errors, see
  114. https://www.kernel.org/doc/man-pages/reporting_bugs.html .