[OpenSPARC-T2-DV] / tools / src / nas,5.n2.os.2 / lib / python / man / man3 / Tcl_GetMathFuncInfo.3

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.AS Tcl_Interp Tcl_CreateInterp in/out
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.TH Tcl_CreateMathFunc 3 8.4 Tcl "Tcl Library Procedures"
.BS
.SH NAME
Tcl_CreateMathFunc, Tcl_GetMathFuncInfo, Tcl_ListMathFuncs \- Define, query and enumerate math functions for expressions
.SH SYNOPSIS
.nf
\fB#include <tcl.h>\fR
.sp
void
\fBTcl_CreateMathFunc\fR(\fIinterp, name, numArgs, argTypes, proc, clientData\fR)
.sp
.VS 8.4
int
\fBTcl_GetMathFuncInfo\fR(\fIinterp, name, numArgsPtr, argTypesPtr, procPtr, clientDataPtr\fR)
.sp
Tcl_Obj *
\fBTcl_ListMathFuncs\fR(\fIinterp, pattern\fR)
.VE
.SH ARGUMENTS
.AS Tcl_ValueType *clientDataPtr
.AP Tcl_Interp *interp in
Interpreter in which new function will be defined.
.VS 8.4
.AP "CONST char" *name in
.VE
Name for new function.
.AP int numArgs in
Number of arguments to new function;  also gives size of \fIargTypes\fR array.
.AP Tcl_ValueType *argTypes in
Points to an array giving the permissible types for each argument to
function.
.AP Tcl_MathProc *proc in
Procedure that implements the function.
.AP ClientData clientData in
Arbitrary one-word value to pass to \fIproc\fR when it is invoked.
.AP int *numArgsPtr out
Points to a variable that will be set to contain the number of
arguments to the function.
.AP Tcl_ValueType **argTypesPtr out
Points to a variable that will be set to contain a pointer to an array
giving the permissible types for each argument to the function which
will need to be freed up using \fITcl_Free\fR.
.AP Tcl_MathProc **procPtr out
Points to a variable that will be set to contain a pointer to the
implementation code for the function (or NULL if the function is
implemented directly in bytecode.)
.AP ClientData *clientDataPtr out
Points to a variable that will be set to contain the clientData
argument passed to \fITcl_CreateMathFunc\fR when the function was
created if the function is not implemented directly in bytecode.
.AP "CONST char" *pattern in
Pattern to match against function names so as to filter them (by
passing to \fITcl_StringMatch\fR), or NULL to not apply any filter.
.BE

.SH DESCRIPTION
.PP
Tcl allows a number of mathematical functions to be used in
expressions, such as \fBsin\fR, \fBcos\fR, and \fBhypot\fR.
\fBTcl_CreateMathFunc\fR allows applications to add additional functions
to those already provided by Tcl or to replace existing functions.
\fIName\fR is the name of the function as it will appear in expressions.
If \fIname\fR doesn't already exist as a function then a new function
is created.  If it does exist, then the existing function is replaced.
\fINumArgs\fR and \fIargTypes\fR describe the arguments to the function.
Each entry in the \fIargTypes\fR array must be
.VS 8.4
one of TCL_INT, TCL_DOUBLE, TCL_WIDE_INT,
or TCL_EITHER to indicate whether the corresponding argument must be an
integer, a double-precision floating value, a wide (64-bit) integer,
or any, respectively.
.VE 8.4
.PP
Whenever the function is invoked in an expression Tcl will invoke
\fIproc\fR.  \fIProc\fR should have arguments and result that match
the type \fBTcl_MathProc\fR:
.CS
typedef int Tcl_MathProc(
	ClientData \fIclientData\fR,
	Tcl_Interp *\fIinterp\fR,
	Tcl_Value *\fIargs\fR,
	Tcl_Value *\fIresultPtr\fR);
.CE
.PP
When \fIproc\fR is invoked the \fIclientData\fR and \fIinterp\fR
arguments will be the same as those passed to \fBTcl_CreateMathFunc\fR.
\fIArgs\fR will point to an array of \fInumArgs\fR Tcl_Value structures,
which describe the actual arguments to the function:
.VS 8.4
.CS
typedef struct Tcl_Value {
	Tcl_ValueType \fItype\fR;
	long \fIintValue\fR;
	double \fIdoubleValue\fR;
	Tcl_WideInt \fIwideValue\fR;
} Tcl_Value;
.CE
.PP
The \fItype\fR field indicates the type of the argument and is
one of TCL_INT, TCL_DOUBLE or TCL_WIDE_INT.
.VE 8.4
It will match the \fIargTypes\fR value specified for the function unless
the \fIargTypes\fR value was TCL_EITHER. Tcl converts
the argument supplied in the expression to the type requested in
\fIargTypes\fR, if that is necessary.
Depending on the value of the \fItype\fR field, the \fIintValue\fR,
.VS 8.4
\fIdoubleValue\fR or \fIwideValue\fR
.VE 8.4
field will contain the actual value of the argument.
.PP
\fIProc\fR should compute its result and store it either as an integer
in \fIresultPtr->intValue\fR or as a floating value in
\fIresultPtr->doubleValue\fR.
It should set also \fIresultPtr->type\fR to one of
.VS 8.4
TCL_INT, TCL_DOUBLE or TCL_WIDE_INT
.VE 8.4
to indicate which value was set.
Under normal circumstances \fIproc\fR should return TCL_OK.
If an error occurs while executing the function, \fIproc\fR should
return TCL_ERROR and leave an error message in the interpreter's result.
.PP
.VS 8.4
\fBTcl_GetMathFuncInfo\fR retrieves the values associated with
function \fIname\fR that were passed to a preceding
\fBTcl_CreateMathFunc\fR call.  Normally, the return code is
\fBTCL_OK\fR but if the named function does not exist, \fBTCL_ERROR\fR
is returned and an error message is placed in the interpreter's
result.
.PP
If an error did not occur, the array reference placed in the variable
pointed to by \fIargTypesPtr\fR is newly allocated, and should be
released by passing it to \fBTcl_Free\fR.  Some functions (the
standard set implemented in the core) are implemented directly at the
bytecode level; attempting to retrieve values for them causes a NULL
to be stored in the variable pointed to by \fIprocPtr\fR and the
variable pointed to by \fIclientDataPtr\fR will not be modified.
.PP
\fBTcl_ListMathFuncs\fR returns a Tcl object containing a list of all
the math functions defined in the interpreter whose name matches
\fIpattern\fR.  In the case of an error, NULL is returned and an error
message is left in the interpreter result, and otherwise the returned
object will have a reference count of zero.
.VE

.SH KEYWORDS
expression, mathematical function

.SH "SEE ALSO"
expr(n), info(n), Tcl_Free(3), Tcl_NewListObj(3)
Commit	Line	Data
86530b38 AT	1	'\"
	2	'\" Copyright (c) 1989-1993 The Regents of the University of California.
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	4	'\"
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	6	'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
	7	'\"
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	9	'\"
	10	'\" The definitions below are for supplemental macros used in Tcl/Tk
	11	'\" manual entries.
	12	'\"
	13	'\" .AP type name in/out ?indent?
	14	'\" Start paragraph describing an argument to a library procedure.
	15	'\" type is type of argument (int, etc.), in/out is either "in", "out",
	16	'\" or "in/out" to describe whether procedure reads or modifies arg,
	17	'\" and indent is equivalent to second arg of .IP (shouldn't ever be
	18	'\" needed; use .AS below instead)
	19	'\"
	20	'\" .AS ?type? ?name?
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	22	'\" name are examples of largest possible arguments that will be passed
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74	.if t .wh -1.3i ^B
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245	..
246	.TH Tcl_CreateMathFunc 3 8.4 Tcl "Tcl Library Procedures"
247	.BS
248	.SH NAME
249	Tcl_CreateMathFunc, Tcl_GetMathFuncInfo, Tcl_ListMathFuncs \- Define, query and enumerate math functions for expressions
250	.SH SYNOPSIS
251	.nf
252	\fB#include <tcl.h>\fR
253	.sp
254	void
255	\fBTcl_CreateMathFunc\fR(\fIinterp, name, numArgs, argTypes, proc, clientData\fR)
256	.sp
257	.VS 8.4
258	int
259	\fBTcl_GetMathFuncInfo\fR(\fIinterp, name, numArgsPtr, argTypesPtr, procPtr, clientDataPtr\fR)
260	.sp
261	Tcl_Obj *
262	\fBTcl_ListMathFuncs\fR(\fIinterp, pattern\fR)
263	.VE
264	.SH ARGUMENTS
265	.AS Tcl_ValueType *clientDataPtr
266	.AP Tcl_Interp *interp in
267	Interpreter in which new function will be defined.
268	.VS 8.4
269	.AP "CONST char" *name in
270	.VE
271	Name for new function.
272	.AP int numArgs in
273	Number of arguments to new function; also gives size of \fIargTypes\fR array.
274	.AP Tcl_ValueType *argTypes in
275	Points to an array giving the permissible types for each argument to
276	function.
277	.AP Tcl_MathProc *proc in
278	Procedure that implements the function.
279	.AP ClientData clientData in
280	Arbitrary one-word value to pass to \fIproc\fR when it is invoked.
281	.AP int *numArgsPtr out
282	Points to a variable that will be set to contain the number of
283	arguments to the function.
284	.AP Tcl_ValueType **argTypesPtr out
285	Points to a variable that will be set to contain a pointer to an array
286	giving the permissible types for each argument to the function which
287	will need to be freed up using \fITcl_Free\fR.
288	.AP Tcl_MathProc **procPtr out
289	Points to a variable that will be set to contain a pointer to the
290	implementation code for the function (or NULL if the function is
291	implemented directly in bytecode.)
292	.AP ClientData *clientDataPtr out
293	Points to a variable that will be set to contain the clientData
294	argument passed to \fITcl_CreateMathFunc\fR when the function was
295	created if the function is not implemented directly in bytecode.
296	.AP "CONST char" *pattern in
297	Pattern to match against function names so as to filter them (by
298	passing to \fITcl_StringMatch\fR), or NULL to not apply any filter.
299	.BE
300
301	.SH DESCRIPTION
302	.PP
303	Tcl allows a number of mathematical functions to be used in
304	expressions, such as \fBsin\fR, \fBcos\fR, and \fBhypot\fR.
305	\fBTcl_CreateMathFunc\fR allows applications to add additional functions
306	to those already provided by Tcl or to replace existing functions.
307	\fIName\fR is the name of the function as it will appear in expressions.
308	If \fIname\fR doesn't already exist as a function then a new function
309	is created. If it does exist, then the existing function is replaced.
310	\fINumArgs\fR and \fIargTypes\fR describe the arguments to the function.
311	Each entry in the \fIargTypes\fR array must be
312	.VS 8.4
313	one of TCL_INT, TCL_DOUBLE, TCL_WIDE_INT,
314	or TCL_EITHER to indicate whether the corresponding argument must be an
315	integer, a double-precision floating value, a wide (64-bit) integer,
316	or any, respectively.
317	.VE 8.4
318	.PP
319	Whenever the function is invoked in an expression Tcl will invoke
320	\fIproc\fR. \fIProc\fR should have arguments and result that match
321	the type \fBTcl_MathProc\fR:
322	.CS
323	typedef int Tcl_MathProc(
324	ClientData \fIclientData\fR,
325	Tcl_Interp *\fIinterp\fR,
326	Tcl_Value *\fIargs\fR,
327	Tcl_Value *\fIresultPtr\fR);
328	.CE
329	.PP
330	When \fIproc\fR is invoked the \fIclientData\fR and \fIinterp\fR
331	arguments will be the same as those passed to \fBTcl_CreateMathFunc\fR.
332	\fIArgs\fR will point to an array of \fInumArgs\fR Tcl_Value structures,
333	which describe the actual arguments to the function:
334	.VS 8.4
335	.CS
336	typedef struct Tcl_Value {
337	Tcl_ValueType \fItype\fR;
338	long \fIintValue\fR;
339	double \fIdoubleValue\fR;
340	Tcl_WideInt \fIwideValue\fR;
341	} Tcl_Value;
342	.CE
343	.PP
344	The \fItype\fR field indicates the type of the argument and is
345	one of TCL_INT, TCL_DOUBLE or TCL_WIDE_INT.
346	.VE 8.4
347	It will match the \fIargTypes\fR value specified for the function unless
348	the \fIargTypes\fR value was TCL_EITHER. Tcl converts
349	the argument supplied in the expression to the type requested in
350	\fIargTypes\fR, if that is necessary.
351	Depending on the value of the \fItype\fR field, the \fIintValue\fR,
352	.VS 8.4
353	\fIdoubleValue\fR or \fIwideValue\fR
354	.VE 8.4
355	field will contain the actual value of the argument.
356	.PP
357	\fIProc\fR should compute its result and store it either as an integer
358	in \fIresultPtr->intValue\fR or as a floating value in
359	\fIresultPtr->doubleValue\fR.
360	It should set also \fIresultPtr->type\fR to one of
361	.VS 8.4
362	TCL_INT, TCL_DOUBLE or TCL_WIDE_INT
363	.VE 8.4
364	to indicate which value was set.
365	Under normal circumstances \fIproc\fR should return TCL_OK.
366	If an error occurs while executing the function, \fIproc\fR should
367	return TCL_ERROR and leave an error message in the interpreter's result.
368	.PP
369	.VS 8.4
370	\fBTcl_GetMathFuncInfo\fR retrieves the values associated with
371	function \fIname\fR that were passed to a preceding
372	\fBTcl_CreateMathFunc\fR call. Normally, the return code is
373	\fBTCL_OK\fR but if the named function does not exist, \fBTCL_ERROR\fR
374	is returned and an error message is placed in the interpreter's
375	result.
376	.PP
377	If an error did not occur, the array reference placed in the variable
378	pointed to by \fIargTypesPtr\fR is newly allocated, and should be
379	released by passing it to \fBTcl_Free\fR. Some functions (the
380	standard set implemented in the core) are implemented directly at the
381	bytecode level; attempting to retrieve values for them causes a NULL
382	to be stored in the variable pointed to by \fIprocPtr\fR and the
383	variable pointed to by \fIclientDataPtr\fR will not be modified.
384	.PP
385	\fBTcl_ListMathFuncs\fR returns a Tcl object containing a list of all
386	the math functions defined in the interpreter whose name matches
387	\fIpattern\fR. In the case of an error, NULL is returned and an error
388	message is left in the interpreter result, and otherwise the returned
389	object will have a reference count of zero.
390	.VE
391
392	.SH KEYWORDS
393	expression, mathematical function
394
395	.SH "SEE ALSO"
396	expr(n), info(n), Tcl_Free(3), Tcl_NewListObj(3)