Issue #7652: Integrate the decimal floating point libmpdec library to speed

up the decimal module. Performance gains of the new C implementation are
between 12x and 80x, depending on the application.

1 files changed, 753 insertions, 0 deletions

diff --git a/Modules/_decimal/docstrings.h b/Modules/_decimal/docstrings.h
new file mode 100644
index 0000000..cf150c7
--- /dev/null
+++ b/Modules/_decimal/docstrings.h
@@ -0,0 +1,753 @@
+/*
+ * Copyright (c) 2001-2012 Python Software Foundation. All Rights Reserved.
+ * Modified and extended by Stefan Krah.
+ */
+
+
+#ifndef DOCSTRINGS_H
+#define DOCSTRINGS_H
+
+
+#include "pymacro.h"
+
+
+/******************************************************************************/
+/*                                Module                                      */
+/******************************************************************************/
+
+
+PyDoc_STRVAR(doc__decimal,
+"C decimal arithmetic module");
+
+PyDoc_STRVAR(doc_getcontext,"\n\
+getcontext() - Get the current default context.\n\
+\n");
+
+PyDoc_STRVAR(doc_setcontext,"\n\
+setcontext(c) - Set a new default context.\n\
+\n");
+
+PyDoc_STRVAR(doc_localcontext,"\n\
+localcontext(c) - Return a context manager that will set the default context\n\
+to a copy of c on entry to the with-statement and restore the previous default\n\
+context when exiting the with-statement. If no context is specified, a copy of\n\
+the current default context is used.\n\
+\n");
+
+#ifdef EXTRA_FUNCTIONALITY
+PyDoc_STRVAR(doc_ieee_context,"\n\
+IEEEContext(bits) - Return a context object initialized to the proper values for\n\
+one of the IEEE interchange formats. The argument must be a multiple of 32 and\n\
+less than IEEE_CONTEXT_MAX_BITS. For the most common values, the constants\n\
+DECIMAL32, DECIMAL64 and DECIMAL128 are provided.\n\
+\n");
+#endif
+
+
+/******************************************************************************/
+/*                       Decimal Object and Methods                           */
+/******************************************************************************/
+
+PyDoc_STRVAR(doc_decimal,"\n\
+Decimal([value[, context]]): Construct a new Decimal object from value.\n\
+\n\
+value can be an integer, string, tuple, or another Decimal object.\n\
+If no value is given, return Decimal('0'). The context does not affect\n\
+the conversion and is only passed to determine if the InvalidOperation\n\
+trap is active.\n\
+\n");
+
+PyDoc_STRVAR(doc_adjusted,"\n\
+adjusted() - Return the adjusted exponent of the number.\n\
+\n\
+Defined as exp + digits - 1.\n\
+\n");
+
+PyDoc_STRVAR(doc_as_tuple,"\n\
+as_tuple() - Return a tuple representation of the number.\n\
+\n");
+
+PyDoc_STRVAR(doc_canonical,"\n\
+canonical() - Return the canonical encoding of the argument. Currently,\n\
+the encoding of a Decimal instance is always canonical, so this operation\n\
+returns its argument unchanged.\n\
+\n");
+
+PyDoc_STRVAR(doc_compare,"\n\
+compare(other[, context]) - Compare self to other. Return a decimal value:\n\
+\n\
+    a or b is a NaN ==> Decimal('NaN')\n\
+    a < b           ==> Decimal('-1')\n\
+    a == b          ==> Decimal('0')\n\
+    a > b           ==> Decimal('1')\n\
+\n");
+
+PyDoc_STRVAR(doc_compare_signal,"\n\
+compare_signal(other[, context]) - Identical to compare, except that\n\
+all NaNs signal.\n\
+\n");
+
+PyDoc_STRVAR(doc_compare_total,"\n\
+compare_total(other) - Compare two operands using their abstract representation\n\
+rather than their numerical value. Similar to the compare() method, but the\n\
+result gives a total ordering on Decimal instances. Two Decimal instances with\n\
+the same numeric value but different representations compare unequal in this\n\
+ordering:\n\
+\n\
+    >>> Decimal('12.0').compare_total(Decimal('12'))\n\
+    Decimal('-1')\n\
+\n\
+Quiet and signaling NaNs are also included in the total ordering. The result\n\
+of this function is Decimal('0') if both operands have the same representation,\n\
+Decimal('-1') if the first operand is lower in the total order than the second,\n\
+and Decimal('1') if the first operand is higher in the total order than the\n\
+second operand. See the specification for details of the total order.\n\
+\n");
+
+PyDoc_STRVAR(doc_compare_total_mag,"\n\
+compare_total_mag(other) - Compare two operands using their abstract\n\
+representation rather than their value as in compare_total(), but\n\
+ignoring the sign of each operand.  x.compare_total_mag(y) is\n\
+equivalent to x.copy_abs().compare_total(y.copy_abs()).\n\
+\n");
+
+PyDoc_STRVAR(doc_conjugate,"\n\
+conjugate() - Return self.\n\
+\n");
+
+PyDoc_STRVAR(doc_copy_abs,"\n\
+copy_abs() - Return the absolute value of the argument. This operation\n\
+is unaffected by the context and is quiet: no flags are changed and no\n\
+rounding is performed.\n\
+\n");
+
+PyDoc_STRVAR(doc_copy_negate,"\n\
+copy_negate() - Return the negation of the argument. This operation is\n\
+unaffected by the context and is quiet: no flags are changed and no\n\
+rounding is performed.\n\
+\n");
+
+PyDoc_STRVAR(doc_copy_sign,"\n\
+copy_sign(other) - Return a copy of the first operand with the sign set\n\
+to be the same as the sign of the second operand. For example:\n\
+\n\
+    >>> Decimal('2.3').copy_sign(Decimal('-1.5'))\n\
+    Decimal('-2.3')\n\
+\n\
+This operation is unaffected by the context and is quiet: no flags are\n\
+changed and no rounding is performed.\n\
+\n");
+
+PyDoc_STRVAR(doc_exp,"\n\
+exp([context]) - Return the value of the (natural) exponential function e**x\n\
+at the given number. The function always uses the ROUND_HALF_EVEN mode and\n\
+the result is correctly rounded.\n\
+\n");
+
+PyDoc_STRVAR(doc_from_float,"\n\
+from_float(f) - Class method that converts a float to a decimal number, exactly.\n\
+Since 0.1 is not exactly representable in binary floating point,\n\
+Decimal.from_float(0.1) is not the same as Decimal('0.1').\n\
+\n\
+    >>> Decimal.from_float(0.1)\n\
+    Decimal('0.1000000000000000055511151231257827021181583404541015625')\n\
+    >>> Decimal.from_float(float('nan'))\n\
+    Decimal('NaN')\n\
+    >>> Decimal.from_float(float('inf'))\n\
+    Decimal('Infinity')\n\
+    >>> Decimal.from_float(float('-inf'))\n\
+    Decimal('-Infinity')\n\
+\n\
+\n");
+
+PyDoc_STRVAR(doc_fma,"\n\
+fma(other, third[, context]) - Fused multiply-add. Return self*other+third\n\
+with no rounding of the intermediate product self*other.\n\
+\n\
+    >>> Decimal(2).fma(3, 5)\n\
+    Decimal('11')\n\
+\n\
+\n");
+
+PyDoc_STRVAR(doc_is_canonical,"\n\
+is_canonical() - Return True if the argument is canonical and False otherwise.\n\
+Currently, a Decimal instance is always canonical, so this operation always\n\
+returns True.\n\
+\n");
+
+PyDoc_STRVAR(doc_is_finite,"\n\
+is_finite() - Return True if the argument is a finite number, and False if the\n\
+argument is infinite or a NaN.\n\
+\n");
+
+PyDoc_STRVAR(doc_is_infinite,"\n\
+is_infinite() - Return True if the argument is either positive or negative\n\
+infinity and False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_is_nan,"\n\
+is_nan() - Return True if the argument is a (quiet or signaling) NaN and\n\
+False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_is_normal,"\n\
+is_normal([context]) - Return True if the argument is a normal finite non-zero\n\
+number with an adjusted exponent greater than or equal to Emin. Return False\n\
+if the argument is zero, subnormal, infinite or a NaN.\n\
+\n");
+
+PyDoc_STRVAR(doc_is_qnan,"\n\
+is_qnan() - Return True if the argument is a quiet NaN, and False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_is_signed,"\n\
+is_signed() - Return True if the argument has a negative sign and\n\
+False otherwise. Note that both zeros and NaNs can carry signs.\n\
+\n");
+
+PyDoc_STRVAR(doc_is_snan,"\n\
+is_snan() - Return True if the argument is a signaling NaN and False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_is_subnormal,"\n\
+is_subnormal([context]) - Return True if the argument is subnormal, and False\n\
+otherwise. A number is subnormal if it is non-zero, finite, and has an\n\
+adjusted exponent less than Emin.\n\
+\n");
+
+PyDoc_STRVAR(doc_is_zero,"\n\
+is_zero() - Return True if the argument is a (positive or negative) zero and\n\
+False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_ln,"\n\
+ln([context]) - Return the natural (base e) logarithm of the operand.\n\
+The function always uses the ROUND_HALF_EVEN mode and the result is\n\
+correctly rounded.\n\
+\n");
+
+PyDoc_STRVAR(doc_log10,"\n\
+log10([context]) - Return the base ten logarithm of the operand.\n\
+The function always uses the ROUND_HALF_EVEN mode and the result is\n\
+correctly rounded.\n\
+\n");
+
+PyDoc_STRVAR(doc_logb,"\n\
+logb([context]) - For a non-zero number, return the adjusted exponent\n\
+of the operand as a Decimal instance. If the operand is a zero, then\n\
+Decimal('-Infinity') is returned and the DivisionByZero condition is\n\
+raised. If the operand is an infinity then Decimal('Infinity') is returned.\n\
+\n");
+
+PyDoc_STRVAR(doc_logical_and,"\n\
+logical_and(other[, context]) - Return the digit-wise and of the two\n\
+(logical) operands.\n\
+\n");
+
+PyDoc_STRVAR(doc_logical_invert,"\n\
+logical_invert([context]) - Return the digit-wise inversion of the\n\
+(logical) operand.\n\
+\n");
+
+PyDoc_STRVAR(doc_logical_or,"\n\
+logical_or(other[, context]) - Return the digit-wise or of the two\n\
+(logical) operands.\n\
+\n");
+
+PyDoc_STRVAR(doc_logical_xor,"\n\
+logical_xor(other[, context]) - Return the digit-wise exclusive or of the\n\
+two (logical) operands.\n\
+\n");
+
+PyDoc_STRVAR(doc_max,"\n\
+max(other[, context]) - Maximum of self and other. If one operand is a quiet\n\
+NaN and the other is numeric, the numeric operand is returned.\n\
+\n");
+
+PyDoc_STRVAR(doc_max_mag,"\n\
+max_mag(other[, context]) - Similar to the max() method, but the comparison is\n\
+done using the absolute values of the operands.\n\
+\n");
+
+PyDoc_STRVAR(doc_min,"\n\
+min(other[, context]) - Minimum of self and other. If one operand is a quiet\n\
+NaN and the other is numeric, the numeric operand is returned.\n\
+\n");
+
+PyDoc_STRVAR(doc_min_mag,"\n\
+min_mag(other[, context]) - Similar to the min() method, but the comparison is\n\
+done using the absolute values of the operands.\n\
+\n");
+
+PyDoc_STRVAR(doc_next_minus,"\n\
+next_minus([context]) - Return the largest number representable in the given\n\
+context (or in the current default context if no context is given) that is\n\
+smaller than the given operand.\n\
+\n");
+
+PyDoc_STRVAR(doc_next_plus,"\n\
+next_plus([context]) - Return the smallest number representable in the given\n\
+context (or in the current default context if no context is given) that is\n\
+larger than the given operand.\n\
+\n");
+
+PyDoc_STRVAR(doc_next_toward,"\n\
+next_toward(other[, context]) - If the two operands are unequal, return the\n\
+number closest to the first operand in the direction of the second operand.\n\
+If both operands are numerically equal, return a copy of the first operand\n\
+with the sign set to be the same as the sign of the second operand.\n\
+\n");
+
+PyDoc_STRVAR(doc_normalize,"\n\
+normalize([context]) - Normalize the number by stripping the rightmost trailing\n\
+zeros and converting any result equal to Decimal('0') to Decimal('0e0'). Used\n\
+for producing canonical values for members of an equivalence class. For example,\n\
+Decimal('32.100') and Decimal('0.321000e+2') both normalize to the equivalent\n\
+value Decimal('32.1').\n\
+\n");
+
+PyDoc_STRVAR(doc_number_class,"\n\
+number_class([context]) - Return a string describing the class of the operand.\n\
+The returned value is one of the following ten strings:\n\
+\n\
+    * '-Infinity', indicating that the operand is negative infinity.\n\
+    * '-Normal', indicating that the operand is a negative normal number.\n\
+    * '-Subnormal', indicating that the operand is negative and subnormal.\n\
+    * '-Zero', indicating that the operand is a negative zero.\n\
+    * '+Zero', indicating that the operand is a positive zero.\n\
+    * '+Subnormal', indicating that the operand is positive and subnormal.\n\
+    * '+Normal', indicating that the operand is a positive normal number.\n\
+    * '+Infinity', indicating that the operand is positive infinity.\n\
+    * 'NaN', indicating that the operand is a quiet NaN (Not a Number).\n\
+    * 'sNaN', indicating that the operand is a signaling NaN.\n\
+\n\
+\n");
+
+PyDoc_STRVAR(doc_quantize,"\n\
+quantize(exp[, rounding[, context]]) - Return a value equal to the first\n\
+operand after rounding and having the exponent of the second operand.\n\
+\n\
+    >>> Decimal('1.41421356').quantize(Decimal('1.000'))\n\
+    Decimal('1.414')\n\
+\n\
+Unlike other operations, if the length of the coefficient after the quantize\n\
+operation would be greater than precision, then an InvalidOperation is signaled.\n\
+This guarantees that, unless there is an error condition, the quantized exponent\n\
+is always equal to that of the right-hand operand.\n\
+\n\
+Also unlike other operations, quantize never signals Underflow, even if the\n\
+result is subnormal and inexact.\n\
+\n\
+If the exponent of the second operand is larger than that of the first, then\n\
+rounding may be necessary. In this case, the rounding mode is determined by the\n\
+rounding argument if given, else by the given context argument; if neither\n\
+argument is given, the rounding mode of the current thread's context is used.\n\
+\n");
+
+PyDoc_STRVAR(doc_radix,"\n\
+radix() - Return Decimal(10), the radix (base) in which the Decimal class does\n\
+all its arithmetic. Included for compatibility with the specification.\n\
+\n");
+
+PyDoc_STRVAR(doc_remainder_near,"\n\
+remainder_near(other[, context]) - Compute the modulo as either a positive\n\
+or negative value depending on which is closest to zero. For instance,\n\
+Decimal(10).remainder_near(6) returns Decimal('-2'), which is closer to zero\n\
+than Decimal('4').\n\
+\n\
+If both are equally close, the one chosen will have the same sign as self.\n\
+\n");
+
+PyDoc_STRVAR(doc_rotate,"\n\
+rotate(other[, context]) - Return the result of rotating the digits of the\n\
+first operand by an amount specified by the second operand. The second operand\n\
+must be an integer in the range -precision through precision. The absolute\n\
+value of the second operand gives the number of places to rotate. If the second\n\
+operand is positive then rotation is to the left; otherwise rotation is to the\n\
+right. The coefficient of the first operand is padded on the left with zeros to\n\
+length precision if necessary. The sign and exponent of the first operand are\n\
+unchanged.\n\
+\n");
+
+PyDoc_STRVAR(doc_same_quantum,"\n\
+same_quantum(other[, context]) - Test whether self and other have the\n\
+same exponent or whether both are NaN.\n\
+\n");
+
+PyDoc_STRVAR(doc_scaleb,"\n\
+scaleb(other[, context]) - Return the first operand with the exponent adjusted\n\
+the second. Equivalently, return the first operand multiplied by 10**other.\n\
+The second operand must be an integer.\n\
+\n");
+
+PyDoc_STRVAR(doc_shift,"\n\
+shift(other[, context]) - Return the result of shifting the digits of\n\
+the first operand by an amount specified by the second operand. The second\n\
+operand must be an integer in the range -precision through precision. The\n\
+absolute value of the second operand gives the number of places to shift.\n\
+If the second operand is positive, then the shift is to the left; otherwise\n\
+the shift is to the right. Digits shifted into the coefficient are zeros.\n\
+The sign and exponent of the first operand are unchanged.\n\
+\n");
+
+PyDoc_STRVAR(doc_sqrt,"\n\
+sqrt([context]) - Return the square root of the argument to full precision.\n\
+The result is correctly rounded using the ROUND_HALF_EVEN rounding mode.\n\
+\n");
+
+PyDoc_STRVAR(doc_to_eng_string,"\n\
+to_eng_string([context]) - Convert to an engineering-type string.\n\
+Engineering notation has an exponent which is a multiple of 3, so\n\
+there are up to 3 digits left of the decimal place. For example,\n\
+Decimal('123E+1') is converted to Decimal('1.23E+3')\n\
+\n");
+
+PyDoc_STRVAR(doc_to_integral,"\n\
+to_integral([rounding[, context]]) - Identical to the to_integral_value()\n\
+method. The to_integral name has been kept for compatibility with older\n\
+versions.\n\
+\n");
+
+PyDoc_STRVAR(doc_to_integral_exact,"\n\
+to_integral_exact([rounding[, context]]) - Round to the nearest integer,\n\
+signaling Inexact or Rounded as appropriate if rounding occurs. The rounding\n\
+mode is determined by the rounding parameter if given, else by the given\n\
+context. If neither parameter is given, then the rounding mode of the current\n\
+default context is used.\n\
+\n");
+
+PyDoc_STRVAR(doc_to_integral_value,"\n\
+to_integral_value([rounding[, context]]) - Round to the nearest integer without\n\
+signaling Inexact or Rounded. The rounding mode is determined by the rounding\n\
+parameter if given, else by the given context. If neither parameter is given,\n\
+then the rounding mode of the current default context is used.\n\
+\n");
+
+
+/******************************************************************************/
+/*                       Context Object and Methods                           */
+/******************************************************************************/
+
+PyDoc_STRVAR(doc_context,"\n\
+The context affects almost all operations and controls rounding,\n\
+Over/Underflow, raising of exceptions and much more. A new context\n\
+can be constructed as follows:\n\
+\n\
+    >>> c = Context(prec=28, Emin=-425000000, Emax=425000000,\n\
+    ...             rounding=ROUND_HALF_EVEN, capitals=1, clamp=1,\n\
+    ...             traps=[InvalidOperation, DivisionByZero, Overflow],\n\
+    ...             flags=[])\n\
+    >>>\n\
+\n\
+\n");
+
+#ifdef EXTRA_FUNCTIONALITY
+PyDoc_STRVAR(doc_ctx_apply,"\n\
+apply(x) - Apply self to Decimal x.\n\
+\n");
+#endif
+
+PyDoc_STRVAR(doc_ctx_clear_flags,"\n\
+clear_flags() - Reset all flags to False.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_clear_traps,"\n\
+clear_traps() - Set all traps to False.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_copy,"\n\
+copy() - Return a duplicate of the context with all flags cleared.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_copy_decimal,"\n\
+copy_decimal(x) - Return a copy of Decimal x.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_create_decimal,"\n\
+create_decimal(x) - Create a new Decimal instance from x, using self as the\n\
+context. Unlike the Decimal constructor, this function observes the context\n\
+limits.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_create_decimal_from_float,"\n\
+create_decimal_from_float(f) - Create a new Decimal instance from float f.\n\
+Unlike the Decimal.from_float() class method, this function observes the\n\
+context limits.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_Etiny,"\n\
+Etiny() - Return a value equal to Emin - prec + 1, which is the minimum\n\
+exponent value for subnormal results. When underflow occurs, the exponent\n\
+is set to Etiny.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_Etop,"\n\
+Etop() - Return a value equal to Emax - prec + 1. This is the maximum exponent\n\
+if the _clamp field of the context is set to 1 (IEEE clamp mode). Etop() must\n\
+not be negative.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_abs,"\n\
+abs(x) - Return the absolute value of x.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_add,"\n\
+add(x, y) - Return the sum of x and y.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_canonical,"\n\
+canonical(x) - Return a new instance of x.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_compare,"\n\
+compare(x, y) - Compare x and y numerically.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_compare_signal,"\n\
+compare_signal(x, y) - Compare x and y numerically. All NaNs signal.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_compare_total,"\n\
+compare_total(x, y) - Compare x and y using their abstract representation.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_compare_total_mag,"\n\
+compare_total_mag(x, y) - Compare x and y using their abstract representation,\n\
+ignoring sign.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_copy_abs,"\n\
+copy_abs(x) - Return a copy of x with the sign set to 0.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_copy_negate,"\n\
+copy_negate(x) - Return a copy of x with the sign inverted.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_copy_sign,"\n\
+copy_sign(x, y) - Copy the sign from y to x.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_divide,"\n\
+divide(x, y) - Return x divided by y.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_divide_int,"\n\
+divide_int(x, y) - Return x divided by y, truncated to an integer.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_divmod,"\n\
+divmod(x, y) - Return quotient and remainder of the division x / y.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_exp,"\n\
+exp(x) - Return e ** x.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_fma,"\n\
+fma(x, y, z) - Return x multiplied by y, plus z.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_is_canonical,"\n\
+is_canonical(x) - Return True if x is canonical, False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_is_finite,"\n\
+is_finite(x) - Return True if x is finite, False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_is_infinite,"\n\
+is_infinite(x) - Return True if x is infinite, False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_is_nan,"\n\
+is_nan(x) - Return True if x is a qNaN or sNaN, False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_is_normal,"\n\
+is_normal(x) - Return True if x is a normal number, False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_is_qnan,"\n\
+is_qnan(x) - Return True if x is a quiet NaN, False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_is_signed,"\n\
+is_signed(x) - Return True if x is negative, False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_is_snan,"\n\
+is_snan() - Return True if x is a signaling NaN, False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_is_subnormal,"\n\
+is_subnormal(x) - Return True if x is subnormal, False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_is_zero,"\n\
+is_zero(x) - Return True if x is a zero, False otherwise.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_ln,"\n\
+ln(x) - Return the natural (base e) logarithm of x.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_log10,"\n\
+log10(x) - Return the base 10 logarithm of x.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_logb,"\n\
+logb(x) - Return the exponent of the magnitude of the operand's MSD.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_logical_and,"\n\
+logical_and(x, y) - Digit-wise and of x and y.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_logical_invert,"\n\
+logical_invert(x) - Invert all digits of x.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_logical_or,"\n\
+logical_or(x, y) - Digit-wise or of x and y.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_logical_xor,"\n\
+logical_xor(x, y) - Digit-wise xor of x and y.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_max,"\n\
+max(x, y) - Compare the values numerically and return the maximum.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_max_mag,"\n\
+max_mag(x, y) - Compare the values numerically with their sign ignored.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_min,"\n\
+min(x, y) - Compare the values numerically and return the minimum.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_min_mag,"\n\
+min_mag(x, y) - Compare the values numerically with their sign ignored.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_minus,"\n\
+minus(x) - Minus corresponds to the unary prefix minus operator in Python,\n\
+but applies the context to the result.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_multiply,"\n\
+multiply(x, y) - Return the product of x and y.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_next_minus,"\n\
+next_minus(x) - Return the largest representable number smaller than x.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_next_plus,"\n\
+next_plus(x) - Return the smallest representable number larger than x.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_next_toward,"\n\
+next_toward(x) - Return the number closest to x, in the direction towards y.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_normalize,"\n\
+normalize(x) - Reduce x to its simplest form. Alias for reduce(x).\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_number_class,"\n\
+number_class(x) - Return an indication of the class of x.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_plus,"\n\
+plus(x) - Plus corresponds to the unary prefix plus operator in Python,\n\
+but applies the context to the result.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_power,"\n\
+power(x, y) - Compute x**y. If x is negative, then y must be integral.\n\
+The result will be inexact unless y is integral and the result is finite\n\
+and can be expressed exactly in 'precision' digits. In the Python version\n\
+the result is always correctly rounded, in the C version the result is\n\
+almost always correctly rounded.\n\
+\n\
+power(x, y, m) - Compute (x**y) % m. The following restrictions hold:\n\
+\n\
+    * all three arguments must be integral\n\
+    * y must be nonnegative\n\
+    * at least one of x or y must be nonzero\n\
+    * m must be nonzero and less than 10**prec in absolute value\n\
+\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_quantize,"\n\
+quantize(x, y) - Return a value equal to x (rounded), having the exponent of y.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_radix,"\n\
+radix() - Return 10.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_remainder,"\n\
+remainder(x, y) - Return the remainder from integer division. The sign of\n\
+the result, if non-zero, is the same as that of the original dividend.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_remainder_near,"\n\
+remainder_near(x, y) - Return x - y * n, where n is the integer nearest the\n\
+exact value of x / y (if the result is 0 then its sign will be the sign of x).\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_rotate,"\n\
+rotate(x, y) - Return a copy of x, rotated by y places.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_same_quantum,"\n\
+same_quantum(x, y) - Return True if the two operands have the same exponent.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_scaleb,"\n\
+scaleb(x, y) - Return the first operand after adding the second value\n\
+to its exp.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_shift,"\n\
+shift(x, y) - Return a copy of x, shifted by y places.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_sqrt,"\n\
+sqrt(x) - Square root of a non-negative number to context precision.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_subtract,"\n\
+subtract(x, y) - Return the difference between x and y.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_to_eng_string,"\n\
+to_eng_string(x) - Convert a number to a string, using engineering notation.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_to_integral,"\n\
+to_integral(x) - Identical to to_integral_value(x).\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_to_integral_exact,"\n\
+to_integral_exact(x) - Round to an integer. Signal if the result is\n\
+rounded or inexact.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_to_integral_value,"\n\
+to_integral_value(x) - Round to an integer.\n\
+\n");
+
+PyDoc_STRVAR(doc_ctx_to_sci_string,"\n\
+to_sci_string(x) - Convert a number to a string using scientific notation.\n\
+\n");
+
+
+#endif /* DOCSTRINGS_H */
+
+
+