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diff --git a/tcllib/idoc/man/files/modules/math/machineparameters.n b/tcllib/idoc/man/files/modules/math/machineparameters.n new file mode 100644 index 0000000..9fcabe4 --- /dev/null +++ b/tcllib/idoc/man/files/modules/math/machineparameters.n @@ -0,0 +1,482 @@ +'\" +'\" Generated from file 'machineparameters\&.man' by tcllib/doctools with format 'nroff' +'\" Copyright (c) 2008 Michael Baudin <michael\&.baudin@sourceforge\&.net> +'\" +.TH "tclrep/machineparameters" n 1\&.0 tcllib "tclrep" +.\" The -*- nroff -*- definitions below are for supplemental macros used +.\" in Tcl/Tk manual entries. +.\" +.\" .AP type name in/out ?indent? +.\" Start paragraph describing an argument to a library procedure. +.\" type is type of argument (int, etc.), in/out is either "in", "out", +.\" or "in/out" to describe whether procedure reads or modifies arg, +.\" and indent is equivalent to second arg of .IP (shouldn't ever be +.\" needed; use .AS below instead) +.\" +.\" .AS ?type? ?name? +.\" Give maximum sizes of arguments for setting tab stops. Type and +.\" name are examples of largest possible arguments that will be passed +.\" to .AP later. If args are omitted, default tab stops are used. +.\" +.\" .BS +.\" Start box enclosure. From here until next .BE, everything will be +.\" enclosed in one large box. +.\" +.\" .BE +.\" End of box enclosure. +.\" +.\" .CS +.\" Begin code excerpt. +.\" +.\" .CE +.\" End code excerpt. +.\" +.\" .VS ?version? ?br? +.\" Begin vertical sidebar, for use in marking newly-changed parts +.\" of man pages. The first argument is ignored and used for recording +.\" the version when the .VS was added, so that the sidebars can be +.\" found and removed when they reach a certain age. If another argument +.\" is present, then a line break is forced before starting the sidebar. +.\" +.\" .VE +.\" End of vertical sidebar. +.\" +.\" .DS +.\" Begin an indented unfilled display. +.\" +.\" .DE +.\" End of indented unfilled display. +.\" +.\" .SO ?manpage? +.\" Start of list of standard options for a Tk widget. The manpage +.\" argument defines where to look up the standard options; if +.\" omitted, defaults to "options". The options follow on successive +.\" lines, in three columns separated by tabs. +.\" +.\" .SE +.\" End of list of standard options for a Tk widget. +.\" +.\" .OP cmdName dbName dbClass +.\" Start of description of a specific option. cmdName gives the +.\" option's name as specified in the class command, dbName gives +.\" the option's name in the option database, and dbClass gives +.\" the option's class in the option database. +.\" +.\" .UL arg1 arg2 +.\" Print arg1 underlined, then print arg2 normally. +.\" +.\" .QW arg1 ?arg2? +.\" Print arg1 in quotes, then arg2 normally (for trailing punctuation). +.\" +.\" .PQ arg1 ?arg2? +.\" Print an open parenthesis, arg1 in quotes, then arg2 normally +.\" (for trailing punctuation) and then a closing parenthesis. +.\" +.\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages. +.if t .wh -1.3i ^B +.nr ^l \n(.l +.ad b +.\" # Start an argument description +.de AP +.ie !"\\$4"" .TP \\$4 +.el \{\ +. ie !"\\$2"" .TP \\n()Cu +. el .TP 15 +.\} +.ta \\n()Au \\n()Bu +.ie !"\\$3"" \{\ +\&\\$1 \\fI\\$2\\fP (\\$3) +.\".b +.\} +.el \{\ +.br +.ie !"\\$2"" \{\ +\&\\$1 \\fI\\$2\\fP +.\} +.el \{\ +\&\\fI\\$1\\fP +.\} +.\} +.. +.\" # define tabbing values for .AP +.de AS +.nr )A 10n +.if !"\\$1"" .nr )A \\w'\\$1'u+3n +.nr )B \\n()Au+15n +.\" +.if !"\\$2"" .nr )B \\w'\\$2'u+\\n()Au+3n +.nr )C \\n()Bu+\\w'(in/out)'u+2n +.. +.AS Tcl_Interp Tcl_CreateInterp in/out +.\" # BS - start boxed text +.\" # ^y = starting y location +.\" # ^b = 1 +.de BS +.br +.mk ^y +.nr ^b 1u +.if n .nf +.if n .ti 0 +.if n \l'\\n(.lu\(ul' +.if n .fi +.. +.\" # BE - end boxed text (draw box now) +.de BE +.nf +.ti 0 +.mk ^t +.ie n \l'\\n(^lu\(ul' +.el \{\ +.\" Draw four-sided box normally, but don't draw top of +.\" box if the box started on an earlier page. +.ie !\\n(^b-1 \{\ +\h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul' +.\} +.el \}\ +\h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul' +.\} +.\} +.fi +.br +.nr ^b 0 +.. +.\" # VS - start vertical sidebar +.\" # ^Y = starting y location +.\" # ^v = 1 (for troff; for nroff this doesn't matter) +.de VS +.if !"\\$2"" .br +.mk ^Y +.ie n 'mc \s12\(br\s0 +.el .nr ^v 1u +.. +.\" # VE - end of vertical sidebar +.de VE +.ie n 'mc +.el \{\ +.ev 2 +.nf +.ti 0 +.mk ^t +\h'|\\n(^lu+3n'\L'|\\n(^Yu-1v\(bv'\v'\\n(^tu+1v-\\n(^Yu'\h'-|\\n(^lu+3n' +.sp -1 +.fi +.ev +.\} +.nr ^v 0 +.. +.\" # Special macro to handle page bottom: finish off current +.\" # box/sidebar if in box/sidebar mode, then invoked standard +.\" # page bottom macro. +.de ^B +.ev 2 +'ti 0 +'nf +.mk ^t +.if \\n(^b \{\ +.\" Draw three-sided box if this is the box's first page, +.\" draw two sides but no top otherwise. +.ie !\\n(^b-1 \h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c +.el \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c +.\} +.if \\n(^v \{\ +.nr ^x \\n(^tu+1v-\\n(^Yu +\kx\h'-\\nxu'\h'|\\n(^lu+3n'\ky\L'-\\n(^xu'\v'\\n(^xu'\h'|0u'\c +.\} +.bp +'fi +.ev +.if \\n(^b \{\ +.mk ^y +.nr ^b 2 +.\} +.if \\n(^v \{\ +.mk ^Y +.\} +.. +.\" # DS - begin display +.de DS +.RS +.nf +.sp +.. +.\" # DE - end display +.de DE +.fi +.RE +.sp +.. +.\" # SO - start of list of standard options +.de SO +'ie '\\$1'' .ds So \\fBoptions\\fR +'el .ds So \\fB\\$1\\fR +.SH "STANDARD OPTIONS" +.LP +.nf +.ta 5.5c 11c +.ft B +.. +.\" # SE - end of list of standard options +.de SE +.fi +.ft R +.LP +See the \\*(So manual entry for details on the standard options. +.. +.\" # OP - start of full description for a single option +.de OP +.LP +.nf +.ta 4c +Command-Line Name: \\fB\\$1\\fR +Database Name: \\fB\\$2\\fR +Database Class: \\fB\\$3\\fR +.fi +.IP +.. +.\" # CS - begin code excerpt +.de CS +.RS +.nf +.ta .25i .5i .75i 1i +.. +.\" # CE - end code excerpt +.de CE +.fi +.RE +.. +.\" # UL - underline word +.de UL +\\$1\l'|0\(ul'\\$2 +.. +.\" # QW - apply quotation marks to word +.de QW +.ie '\\*(lq'"' ``\\$1''\\$2 +.\"" fix emacs highlighting +.el \\*(lq\\$1\\*(rq\\$2 +.. +.\" # PQ - apply parens and quotation marks to word +.de PQ +.ie '\\*(lq'"' (``\\$1''\\$2)\\$3 +.\"" fix emacs highlighting +.el (\\*(lq\\$1\\*(rq\\$2)\\$3 +.. +.\" # QR - quoted range +.de QR +.ie '\\*(lq'"' ``\\$1''\\-``\\$2''\\$3 +.\"" fix emacs highlighting +.el \\*(lq\\$1\\*(rq\\-\\*(lq\\$2\\*(rq\\$3 +.. +.\" # MT - "empty" string +.de MT +.QW "" +.. +.BS +.SH NAME +tclrep/machineparameters \- Compute double precision machine parameters\&. +.SH SYNOPSIS +package require \fBsnit \fR +.sp +package require \fBmath::machineparameters 0\&.1\fR +.sp +\fBmachineparameters\fR create \fIobjectname\fR ?\fIoptions\fR\&.\&.\&.? +.sp +\fIobjectname\fR \fBconfigure\fR ?\fIoptions\fR\&.\&.\&.? +.sp +\fIobjectname\fR \fBcget\fR \fIopt\fR +.sp +\fIobjectname\fR \fBdestroy\fR +.sp +\fIobjectname\fR \fBcompute\fR +.sp +\fIobjectname\fR \fBget\fR \fIkey\fR +.sp +\fIobjectname\fR \fBtostring\fR +.sp +\fIobjectname\fR \fBprint\fR +.sp +.BE +.SH DESCRIPTION +The \fImath::machineparameters\fR package +is the Tcl equivalent of the DLAMCH LAPACK function\&. +In floating point systems, a floating point number is represented +by +.CS + + +x = +/- d1 d2 \&.\&.\&. dt basis^e + +.CE +where digits satisfy +.CS + + +0 <= di <= basis - 1, i = 1, t + +.CE +with the convention : +.IP \(bu +t is the size of the mantissa +.IP \(bu +basis is the basis (the "radix") +.PP +.PP +The \fBcompute\fR method computes all machine parameters\&. +Then, the \fBget\fR method can be used to get each +parameter\&. +The \fBprint\fR method prints a report on standard output\&. +.SH EXAMPLE +In the following example, one compute the parameters of a desktop +under Linux with the following Tcl 8\&.4\&.19 properties : +.CS + + +% parray tcl_platform +tcl_platform(byteOrder) = littleEndian +tcl_platform(machine) = i686 +tcl_platform(os) = Linux +tcl_platform(osVersion) = 2\&.6\&.24-19-generic +tcl_platform(platform) = unix +tcl_platform(tip,268) = 1 +tcl_platform(tip,280) = 1 +tcl_platform(user) = <username> +tcl_platform(wordSize) = 4 + +.CE +The following example creates a machineparameters object, +computes the properties and displays it\&. +.CS + + + set pp [machineparameters create %AUTO%] + $pp compute + $pp print + $pp destroy + +.CE +This prints out : +.CS + + + Machine parameters + Epsilon : 1\&.11022302463e-16 + Beta : 2 + Rounding : proper + Mantissa : 53 + Maximum exponent : 1024 + Minimum exponent : -1021 + Overflow threshold : 8\&.98846567431e+307 + Underflow threshold : 2\&.22507385851e-308 + +.CE +That compares well with the results produced by Lapack 3\&.1\&.1 : +.CS + + + Epsilon = 1\&.11022302462515654E-016 + Safe minimum = 2\&.22507385850720138E-308 + Base = 2\&.0000000000000000 + Precision = 2\&.22044604925031308E-016 + Number of digits in mantissa = 53\&.000000000000000 + Rounding mode = 1\&.00000000000000000 + Minimum exponent = -1021\&.0000000000000 + Underflow threshold = 2\&.22507385850720138E-308 + Largest exponent = 1024\&.0000000000000 + Overflow threshold = 1\&.79769313486231571E+308 + Reciprocal of safe minimum = 4\&.49423283715578977E+307 + +.CE +The following example creates a machineparameters object, +computes the properties and gets the epsilon for +the machine\&. +.CS + + + set pp [machineparameters create %AUTO%] + $pp compute + set eps [$pp get -epsilon] + $pp destroy + +.CE +.SH REFERENCES +.IP \(bu +"Algorithms to Reveal Properties of Floating-Point Arithmetic", Michael A\&. Malcolm, Stanford University, Communications of the ACM, Volume 15 , Issue 11 (November 1972), Pages: 949 - 951 +.IP \(bu +"More on Algorithms that Reveal Properties of Floating, Point Arithmetic Units", W\&. Morven Gentleman, University of Waterloo, Scott B\&. Marovich, Purdue University, Communications of the ACM, Volume 17 , Issue 5 (May 1974), Pages: 276 - 277 +.PP +.SH "CLASS API" +.TP +\fBmachineparameters\fR create \fIobjectname\fR ?\fIoptions\fR\&.\&.\&.? +The command creates a new machineparameters object and returns the fully +qualified name of the object command as its result\&. +.RS +.TP +\fB-verbose\fR \fIverbose\fR +Set this option to 1 to enable verbose logging\&. +This option is mainly for debug purposes\&. +The default value of \fIverbose\fR is 0\&. +.RE +.PP +.SH "OBJECT API" +.TP +\fIobjectname\fR \fBconfigure\fR ?\fIoptions\fR\&.\&.\&.? +The command configure the options of the object \fIobjectname\fR\&. The options +are the same as the static method \fBcreate\fR\&. +.TP +\fIobjectname\fR \fBcget\fR \fIopt\fR +Returns the value of the option which name is \fIopt\fR\&. The options +are the same as the method \fBcreate\fR and \fBconfigure\fR\&. +.TP +\fIobjectname\fR \fBdestroy\fR +Destroys the object \fIobjectname\fR\&. +.TP +\fIobjectname\fR \fBcompute\fR +Computes the machine parameters\&. +.TP +\fIobjectname\fR \fBget\fR \fIkey\fR +Returns the value corresponding with given key\&. +The following is the list of available keys\&. +.RS +.IP \(bu +-epsilon : smallest value so that 1+epsilon>1 is false +.IP \(bu +-rounding : The rounding mode used on the machine\&. +The rounding occurs when more than t digits would be required to +represent the number\&. +Two modes can be determined with the current system : +"chop" means than only t digits are kept, no matter the value of the number +"proper" means that another rounding mode is used, be it "round to nearest", +"round up", "round down"\&. +.IP \(bu +-basis : the basis of the floating-point representation\&. +The basis is usually 2, i\&.e\&. binary representation (for example IEEE 754 machines), +but some machines (like HP calculators for example) uses 10, or 16, etc\&.\&.\&. +.IP \(bu +-mantissa : the number of bits in the mantissa +.IP \(bu +-exponentmax : the largest positive exponent before overflow occurs +.IP \(bu +-exponentmin : the largest negative exponent before (gradual) underflow occurs +.IP \(bu +-vmax : largest positive value before overflow occurs +.IP \(bu +-vmin : largest negative value before (gradual) underflow occurs +.RE +.TP +\fIobjectname\fR \fBtostring\fR +Return a report for machine parameters\&. +.TP +\fIobjectname\fR \fBprint\fR +Print machine parameters on standard output\&. +.PP +.SH "BUGS, IDEAS, FEEDBACK" +This document, and the package it describes, will undoubtedly contain +bugs and other problems\&. +Please report such in the category \fImath\fR of the +\fITcllib Trackers\fR [http://core\&.tcl\&.tk/tcllib/reportlist]\&. +Please also report any ideas for enhancements you may have for either +package and/or documentation\&. +.SH COPYRIGHT +.nf +Copyright (c) 2008 Michael Baudin <michael\&.baudin@sourceforge\&.net> + +.fi
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